Global Energy Scenario and Impact Of

7/30/2019 Global Energy Scenario and Impact Of

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2638 IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 60, NO. 7, JULY 2013

Global Energy Scenario and Impact ofPower Electronics in 21st Century

Bimal K. Bose, Life Fellow, IEEE

AbstractPower electronics technology has gained signifi-cant maturity after several decades of dynamic evolution ofpower semiconductor devices, converters, pulse width modulation(PWM) techniques, electrical machines, motor drives, advancedcontrol, and simulation techniques. According to the estimate ofthe Electric Power Research Institute, roughly 70% of electricalenergy in the USA now flows through power electronics, whichwill eventually grow to 100%. In the 21st century, we expect tosee the tremendous impact of power electronics not only in globalindustrialization and general energy systems, but also in energysaving, renewable energy systems, and electric/hybrid vehicles.The resulting impact in mitigating climate change problems is

expected to be enormous. This paper, in the beginning, will discussthe global energy scenario, climate change problems, and themethods of their mitigation. Then, it will discuss the impact ofpower electronics in energy saving, renewable energy systems,bulk energy storage, and electric/hybrid vehicles. Finally, it willreview several example applications before coming to conclusionand future prognosis.

Index TermsClimate change, electric/hybrid vehicles, energy,energy storage, future of power electronics, global warming, motordrives, power electronics, renewable energy systems.

I. INTRODUCTION

IT IS well known that power electronics is based on high

efficiency and fast-switching silicon power semiconductor

switches, such as diode, thyristor, triac, gate turn-off thyris-tor (GTO), power MOSFET, insulated gate bipolar transistor

(IGBT), and integrated gate-commutated thyristor (IGCT), and

their applications include dc and ac regulated power supplies,

uninterruptible power supply (UPS) systems, electrochemical

processes (such as electroplating, electrolysis, anodizing, and

metal refining), heating and lighting control, electronic weld-

ing, power line static volt ampere reactive (VAR) compensators

[SVC, static var generator, or static synchronous compensator

(STATCOM)] and flexible ac transmission systems (FACTS),

active harmonic filters (AHFs), HVdc systems, photovoltaic

(PV) and fuel cell (FC) converters, dc and ac circuit break-

ers, high-frequency heating, energy storage, and dc/ac motordrives. Motor drive area may include applications in comput-

ers and peripherals, solid-state motor starters, transportation

Manuscript received October 17, 2011; revised January 3, 2012 andMarch 28, 2012; accepted May 25, 2012. Date of publication June 8, 2012; dateof current version February 28, 2013. This paper was presented in part as aninvited keynote address in Qatar Workshop on Power Electronics in IndustrialApplications and Renewable Energy (PEIA2011), Doha, November 34, 2011.The Workshop was sponsored by the IEEE Industrial Electronics Society.

The author is with the Department of Electrical Engineering and ComputerScience, University of Tennessee, Knoxville, TN 37996-2100 USA (e-mail:[email protected]).

Color versions of one or more of the figures in this paper are available onlineat http://ieeexplore.ieee.org.

Digital Object Identifier 10.1109/TIE.2012.2203771

systems, home appliances, paper and textile mills, pumps and

compressors, rolling and cement mills, machine tools and

robotics, variable-speed constant-frequency systems, etc. The

widespread applications of power electronics in global industri-

alization are bringing a kind of industrial revolution in the 21st

century which has been somewhat unprecedented in history. We

have already seen how computer, communication, and infor-

mation technology advancements have turned geographically

remote countries as close neighbors. In particular, the Internet

communication has brought revolution in our society, bringing

the whole world close together into a global village. Truly,we now live in a global society, where the nations in the

world are being increasingly interdependent. What happens

today in India or Egypt, for example, affects the USA and

vice versa. In the present trend, it is expected that future wars

in the world will be fought in economic front rather than

in military front. In the global marketplace, free from trade

barriers, all the nations in the world will face fierce industrial

competitiveness for survival and prosperity of living standard.

In such an environment, power electronics with motion control

will play a dominant role in the 21st century. Moreover, as

the energy price increases and environmental regulations are

tightened, power electronics applications will spread in every

corner of industrial, commercial, residential, transportation,aerospace, military, and utility systems. The role of power

electronics in this era will be as important as that of computers,

communication, and information technologies, if not more.

It may be relevant to mention here that the author recently

published two survey papers [1], [2] of which the first paper

has no relevance to the content of this paper. This paper is

comprehensive and mainly deals with the discussion of energy

systems. The technology advancement and trends are briefly

reviewed in the Future Scenario of Section VI which can be

considered as supplementary to the second paper [2].

II. ENERGY SCENARIO

Let us discuss, in the beginning, with the global energy

scenario [6][9]. We have come a long way in the history of

our industrial civilization. Prior to industrial revolution, which

started in 1785, we were essentially in the muscle age when

our energy primarily came from human and animal muscles.

In those days, world population was small, life was simple and

unsophisticated, and the environment was relatively clean. The

mechanical age, or the age of steam and heat engines, started

with industrial revolution. Then, the electrical age started in

the late nineteenth century by the commercial availability of

electricity and, particularly, by the invention of commercial

0278-0046/$31.00 2012 IEEE


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BOSE: GLOBAL ENERGY SCENARIO AND IMPACT OF POWER ELECTRONICS IN 21st CENTURY 2639

Fig. 1. Global and U.S. energy generation scenario (2008).

induction motor. Then, the age of modern solid-state electronics

started by the invention of the transistor in 1948. Commercial

thyristor was introduced in 1958, setting the age of modern

solid-state power electronics or what we often call The Second

Electronics or Power Electronics Revolution. Then gradually

came the age of integrated circuits (ICs), computers, commu-

nication, and roboticsand now, we live in the Internet age.

During the mechanical, electrical, and electronics ages, theenergy consumption in the world was growing by leaps and

bounds to cater the need of growing global population and

the quest for higher living standard. So far, we hardly paid

any attention to the adverse effect of energy consumption, i.e.,

environmental pollution.

Fig. 1 shows the global energy generation (or consumption)

scenario and the U.S. energy generation in the same perspec-

tive. Around 84% of the total energy in the world is generated

by fossil fuels (coal, oil, and natural gas), 3% from nuclear

plants, and the remaining 13% comes from renewable sources,

such as hydro, wind, solar, biofuels, geothermal, wave, and tidal

power. The U.S. energy generation pattern is essentially similar.About 41% of the U.S. energy comes from oil which is

mainly used in automobile transportation. It is interesting to

note that about 70% of the U.S. oil is imported from outside

of which a bulk is from the Middle East, and this is the possible

reason for so much turmoil there. Again, it is interesting to note

that per capita energy consumption in the world is highest in the

USA. With nearly 4% of the world population (313 million out

of 7 billion), the USA consumes nearly 28% of global energy,

and this reflects a very high living standard (Switzerland has

now the highest living standard). In comparison, China (now

the worlds second largest economy) with nearly 20% of the

world population (1.3 billion) consumes almost the same total

energy as that of the USA. Of course, this scenario is changingfast because of the rapid industrialization of China.

Fig. 2. Idealized fossil and nuclear energy depletion curves of the world(2008).

Fig. 2 shows the idealized energy depletion curves of fossil

and nuclear fuels of the world (updated from [10]), considering

the present availability and the current rate of consumption.

The world has enormous reserve of coal, and at the present

consumption rate, it is expected to last around 200 years.

Looking at the oil depletion curve, it appears to be near the peak

now and is expected to be exhausted in 100 years. The recent

rise of oil price is natural because the demand is rising and the

supply is dwindling. The natural gas reserve is expected to last

around 150 years. Natural uranium (U235) has very low reserve

and is expected to last around 50 years. Of course, it is possible

to generate new nuclear fuel in breeder reactor.How will we fly our airplanes and run our automobiles when

oil gets totally exhausted? Of course, some fossil fuels can be

converted from one form to another which may be expensive.

With proper conservation, the curves in the figure can be

flattened. Discovery and exploration of new fuel resources,

particularly offshore oil and gas, can provide new resources.

It is believed that the Arctic Ocean contains the worlds 25%

oil and gas reserves, the exploration of which can be expensive.

Note that Fig. 2 does not include renewable energy resources,

which will theoretically extend the energy depletion curve to

infinity. It is no wonder that, because of competitive costs

and extensive availability and because they are environmentallyclean in nature, renewable sources are now getting so much

emphasis all over the world. Recent study (will be discussed

later) has indicated that renewable energy alone with adequate

storage can supply all the energy needs of the world. Again,

fusion energy does not yet show any promise for the future.

Fig. 3 shows electricity generation by different fuel types for

a few selected countries of the world. For example, in the USA,

40% of the total energy is consumed in electrical form of which

nearly 50% comes from coal, 2% from oil, 18% from natural gas,

20% from nuclear plants, and the remaining 10% comes from

renewables (mainly hydro). The gas-generated electricity is be-

ing favoredmore (with the corresponding decrease from coal) be-

cause of the recent availability of cheap and abundant shale gas.Japan had 31% electricity from nuclear resource, but the recent


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Fig. 3. Electricity generation by fuel types of some selected countries (2008).

Fig. 4. Per capita CO2 emission versus population of some selected countries.

nuclear accident in the Fukushima-Daiichi plant is altering the

scenario, emphasizing more on renewable resources. Interest-

ingly, the worlds two most fast developing economies (China

and India) generate most of the electricity by burning coal.

III. CLIMATE CHANGE PROBLEMSMETHODS

OF MITIGATION

Unfortunately, burning of fossil fuels (coal, oil, and naturalgas) generates pollutant gases (SO2, CO, NOX, HC, and CO2)

that cause environmental pollution problems. For example, acid

rain that destroys vegetation is caused by SO2 and NOX, and

urban pollution is caused mainly by automobile exhaust gases

(CO, NOX, and HC). The more dominant effect of fossil fuel

burning is the climate change problem [6] that is mainly caused

by CO2 [also methane (CH4) and other gasescalled green-house gases (GHGs)], which traps solar heat in the atmosphere.

The United Nations (UN) Intergovernmental Panel on Climate

Change (IPCC) has ascertained with 90% certainty that man-

made burning of fossil fuels causes climate change problem.

Fig. 4 shows the per capita CO2 emission versus population of

some selected countries in the world. The horizontal axis showsthe population of the countries, and the vertical axis shows the

CO2 emission per person (in tons/yr.). It is interesting to note

that the USA has the highest per capita emission in the world

(excluding some Middle-East countries), and Canada is very

close. Next is Australia, and the European nations, as well as

Russia and Japan, are typically less than 50% of that of the

USA. Although Switzerland has the highest standard of living,

its emission level is moderate, as shown. The total emission in

a country, given by the area of the rectangle, is very important.

The standard of living in China is much lower than that of the

USA, and its per capita emission is very low. However, because

of large population, the total emission in China is large and, in

fact, exceeded that of the USA from 2006. The USA refuses to

accept mandatory emission control unless China takes adequate

remedial action. On the other hand, China blames the USA and

other industrialized nations for creating this mess and is not

willing to sacrifice its growing standard of living by reducing

energy consumption. Interestingly, Brazil has good standard of

living but low per capita emission. In Brazil, typically 90% of

energy (in electrical form) comes from hydro, it has large CO2sinking Amazon rain forest, and 50% of its automobiles run on

renewable sugarcane-based biofuel. Biofuels are said to have

carbon neutralization effect because they absorb CO2 duringplant growth but emit CO2 at burning.


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What are the effects of climate change? As mentioned before,

GHG causes the Earths atmosphere to accumulate solar heat

and raise its temperature that may be a few degrees in 100 years.

Note that a significant amount of global warming is caused

by water vapor and cloud that act as bias and help to sustain

plant and animal life on Earth. Climate scientists are trying

to model the climate system (extremely complex) and predictatmospheric temperature rise by extensive simulation study on

supercomputers. The most serious effect of global warming

is the melting ice in the Arctic, the Antarctic, Greenland, the

Himalayas, and thousands of glaciers around the world that will

cause the inundation of low-lying areas. In fact, the study has

shown that Arctic ice shrank by 500 000 mi2 in 2006 alone,

which is three times faster than the computer prediction by

climate scientists. This is very baffling to the scientists. The

melting of ice is raising the sea level with the potential to

flood the low-lying areas. It has been estimated that about

100 million people live within 3 ft of the sea level, and they will

experience flooding of their habitats. Again, with the projected

rise of the sea level, it is estimated that 50% of Bangladesh will

be under water in 300 years, which will displace 75 million

people. It has been predicted that, if all the ice in Greenland

and Antarctica melts, the sea level will rise by 200 ft. The

city of Manhattan in New York will be under 200-ft water if

all the ice in two polar ice caps melts. The Arctic region will

be virtually free from ice by 2070. The melting of the Arctic

ice is removing the habitats of polar bears and penguins with

the expected extinction of these species. The highly sensitive

corals in the sea are dying due to higher water temperature and

acidity of dissolved CO2. Aside from sea level rise, climate

change will bring severe droughts in tropical countries (like

Africa and India). This will damage the agriculture and veg-etation, bring hurricanes, tornadoes, heavy rains, and floods,

and spread diseases. For example, according to UN, Indias

agricultural production is expected to decrease by 38% by 2080

due to drought, but carbon fertilization will offset it by 9%.

Again, according to UN estimate, if all fossil fuel burning is

completely stopped today, the ocean level will rise by 4.6 ft in

the next 1000 years. All these climate change effects will bring

tremendous unrest and instability in the world. Considering the

serious consequences, the UN Kyoto Protocol emerged in 1997.

Under this treaty, each member country is required to limit

emission within a certain quota. Unfortunately, the Kyoto Pro-

tocol implementation is not being very successful in the recentyears.

How can we solve or mitigate the climate change problems?

The methods can be summarized as follows [7], [8].

1) Promote all of our energy consumption in electrical form.

Centralized fossil fuel power stations can use emission

control strategy effectively.

2) Cut down or eliminate coal-fired power generation. Else,

develop clean coal technology with CO2 capture and

underground sequestration.

3) Increase nuclear power(?). Nuclear power has usual

safety and radioactive waste problems.

(The trend is tending to reverse after the recent

Fukushima-Daiichi nuclear power plant accident inJapan.)

4) Since trees absorb CO2, preserve rain forests in the world,

and promote widespread forestation.

5) Control human and animal population since they exhale

GHG. Moreover, larger population means more energy

consumption. This method is not easy.

6) Promote the generation of environmentally clean

energy.7) Replace internal combustion engine (ICE) vehicles by

electric vehicles (EVs)/hybrid electric vehicles (HEVs).

8) Promote mass electrical transportation.

9) Save energy by more efficient generation, transmission,

distribution, and utilization of electricity, which is the

goal of future smart grid [11], [12].

10) Finally, energy wastage must be prevented, and its con-

sumption should be economized to make the lifestyle

simpler. It has been estimated that almost 33% of energy

in the world can be saved by this method.

There are, of course, a few beneficial effects of climate

change. As mentioned before, 25% of the worlds oil and

gas reserves below the Arctic Ocean will be available for

exploration. The carbon fertilization effect will benefit agricul-

ture and plants. The melting of polar ice caps will open new

transoceanic shipping routes. In addition, the melting of ice

will recover new lands that will be available for habitation and

agriculture.

IV. IMPACT OF POWER ELECTRONICS

Let us now fall back to power electronics and explain why

it is so important today not only for industrialization and

general energy systems but also for energy saving and, thus,

for mitigating climate change problems. As you know, power

electronics deals with conversion and control of electrical

power with the help of power semiconductor devices that

operate in switching mode, and therefore, the efficiency of

power electronic apparatus may approach as high as 98%99%.

With the advancement of technology, as the cost of power

electronics decreased significantly, size became smaller, and

the performance improved; power electronics applications are

proliferating in industrial, commercial, residential, aerospace,

military, utility, and transportation systems. In industrial sys-

tems, power electronics helps productivity improvement with

the improvement of product quality. Another important role of

power electronics, which is getting strong emphasis recently,is the energy saving. This will be discussed separately. In

addition, the impact of power electronics in renewable energy

systems, bulk energy storage, and electric/hybrid vehicles is

significant in solving our energy shortage [13], which will be

discussed next.

A. Energy Saving

The high efficiency of power electronics-based energy sys-

tems has been discussed before. Saving of energy gives the

financial benefit directly, particularly where the energy cost

is high. The extra cost of power electronics can be recoveredwithin a reasonable period. In addition, reduced consumption


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means reduced generation that indirectly mitigates the

environmental pollution and climate change problems. Power

electronic control instead of traditional rheostatic or motor/

generator set control is obviously more efficient. In many parts

of the world, rheostatic speed control of subway drives is still

used. According to the Electric Power Research Institute of the

USA, nearly 60%65% of grid-generated energy in the USAis consumed by electrical motor drives, and 75% of these are

pump, fan, and compressor-type drives. The majority of the

pumps and fans are used in industrial environment for the con-

trol of fluid flow. In such applications, the traditional method of

flow control is by variable throttle or damper opening, where an

induction motor coupled to the pump runs at constant speed (in

the USA, 96% of large drives still use this traditional method).

This method causes a lot of energy wastage by fluid vortex.

In such applications, variable-frequency motor speed control

with fully open throttle can save around 20% energy at light

load. Again, converter-fed machine efficiency can be improved

further by flux programming at light load. Power electronics-

based load-proportional speed control of air conditioner/heat

pump can save energy by up to 20%. One popular application

of power electronics in recent years is variable-frequency drive

in diesel-electric ship propulsion, which can save considerable

amount of fuel compared with the traditional diesel-turbine

drive. It has been estimated that around 20% of grid energy

in the USA is consumed in lighting. Power electronics-based

compact fluorescent lamps (CFLs) are typically four times more

efficient than incandescent lamps, besides having longer (ten

times) life. Some countries have already banned incandescent

lamps. Currently, the emerging solid-state LED lamps consume

50% less energy than CFLs and have five times longer life.

High efficiency induction and microwave cooking also save alot of energy. The smart or intelligent grid of tomorrow will ex-

tensively use state-of-the-art power electronics, computers, and

communication technologies and will permit optimum resource

utilization, economical electricity to customers, higher energy

efficiency, higher reliability, and improved system security. In

fact, indirectly, one goal of the smart grid is to gradually

transition us toward future carbon-free society. It has been

estimated that the widespread efficiency improvement by power

electronics and other methods with the existing technologies

can save 20% of the global energy demand, and another 20%

can be saved by preventing waste.

B. Renewable Energy Systems

As mentioned before, renewable energy resources, such

as hydro, wind, solar, biofuels, geothermal, wave, and tidal

powers, are environmentally clean and abundant in nature

and therefore are getting tremendous emphasis all over the

world. Scientific American has recently published a paper

[16] by Stanford University professors that predicts that re-

newable energies only with adequate storage can supply all

the energy needs of the world. Another study by UN IPCC

reports that 50% of the total world energy can be met by

renewable resources by 2050. After the recent nuclear accident

in Japan, both Japan and Germany (Germany will exit fromnuclear power by 2022) are planning to heavily emphasize

renewable energy. The wind and solar resources, which are

heavily dependent on power electronics for conversion and

control, are particularly important to meet our growing energy

needs and mitigate the climate change problems. Note that

solar energy can be two types: One is thermal through solar

concentrators that generates steam and operates turbogener-

ators to generate electricity (like conventional steam powerplant), and the other is PV generation of electricity by silicon

semiconductor.

1) Wind Energy Scenario: In a modern wind generation

system, the energy from the wind is converted to electricity

by a generator coupled to a variable-speed wind turbine. The

variable-voltage variable-frequency power is then converted to

constant voltage and frequency by a converter system before

feeding to the grid. The world has enormous wind energy

resources, and they are the most economical green energy.

According to the estimate of the European Wind Energy Asso-

ciation, the exploration of only 10% (Stanford University esti-

mate is 20%) of the available resource can possibly supply all

the electricity needs of the world. Recent technology advances

in variable-speed wind turbines, power electronics, and ma-

chine drives have made wind energy very competitivealmost

equal to that of fossil fuel power. Wind and PV energy are par-

ticularly attractive to the one-third of the world population that

lives outside the electric grid. Among the developing countries,

for example, China and India have large expansion programs

for wind energy. Currently, in terms of percentage energy

consumption, Denmark is the leader with 25% of wind energy,

which is expected to rise to 40% by 2030. In terms of installed

capacity, China is the leader, and the USA occupies the second

place (close to Germany and Spain) with a total penetration

of slightly more than 3%. The USA has the ambitious goalof increasing it to 20% by 2030. The wind potential of the

USA is so huge that it can meet more than twice its current

electricity need. The state of North Dakota alone has 2.5 times

the total potential capacity of Germany. One drawback of wind

energy is that its availability is statistical in nature and may

require backup power from fossil or nuclear power plants. Of

course, surplus wind generated energy can be stored (storage

will be discussed later) for lean time utilization. Offshore

wind farms generally give higher energy output than onshore

farms, although their installation and maintenance are more

expensive.

2) PV Energy Scenario:PV devices (crystalline or amor-phous Si, CdTe, and copper indium gallium selenide) convert

sunlight directly into electricity. The generated dc is then con-

verted to ac and fed to the grid or used in autonomous load. The

PV devices are static, safe, reliable, and environmentally clean

(green) and do not require any repair and maintenance like wind

power systems. However, in the current state of the technology,

PV energy is generally typically three times more expensive

than wind energy, but it truly depends on the utilization factor.

Although, currently, PV energy is more expensive than that of

solar thermal, with the present trend of aggressive research, the

price is falling sharply to be more competitive in future. The

PV energy is expected to have significant expansion around the

world. The IEEE has ambitious prediction that, by 2050, PVwill supply 11% of the global electricity demand. The lifetime


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Fig. 5. FC-based EV showing H2 generation methods.

of PV panel is typically 20 years, and conversion efficiency is

typically 15% with the commonly used thin-film amorphous

silicon. PV power has been extensively used in space appli-

cations, although their applications are recently expanding to

rooftop installation and off-grid remote installations like windpower. Japan has very aggressive role in PV research and

applications because it does not have much indigenous energy

resources and energy is expensive there. The recent accident in

the Fukushima-Daiichi nuclear reactors is now putting Japans

emphasis shift from nuclear to PV resources. Unfortunately,

like wind power, PV is also sporadic and therefore requires

backup energy sources or bulk storage, or else, the recent smart

grid concept can shift the energy demand curve to match with

the available curve. Currently, there are ambitious plans to

explore solar energy from the African deserts like Sahara and

Kalahari through extensive PV installations [14] and tying to

the European grid through HVdc transmission.

3) FC Energy Scenario: In an FC, H2 gas is the fuel, and it

combines with oxygen to produce electricity and water. The FC

stacks can be considered as equivalent to series-connected low-

voltage batteries. The dc voltage generated by FC is normally

stepped up by a dcdc converter and then converted to ac by

an inverter for ac power supply. An FC is characterized by

high output resistance and sluggish transient response (due

to polarization effect). H2 can be generated from water by

electrolysis or from hydrocarbon fuels (gasoline and methanol)

through a reformer. An FC can be defined as a clean energy

source if H2 is generated from a clean energy source. FC is safe

and static and has high efficiency (typically 54%). The FC types

can be classified as proton exchange membrane FC (PEMFC),phosphoric acid FC, direct methanol FC, and solid-state FC.

All of them are available commercially, but PEMFC is the

most economical with high power density and low temperature

(60 C100 C) and therefore is important for FC-based electric

cars. FCs can also be used for building cogeneration, distributed

power source for utility system, and UPS system or as portablepower source. Although it is bulky and expensive in the present

state of the technology, extensive R&D is recently reducing the

cost of FC dramatically. Fig. 5 shows the principle of FC-based

EV that also summarizes different methods of H2 generation.

In an FC vehicle, a PEMFC usually generates the dc power,

which is boosted by a dcdc converter and then converted to

variable-frequency variable-voltage power for driving an ac

motor. Since FC cannot absorb vehicle regenerative power, a

battery or ultracapacitor (UC) is needed at the FC terminal

[through another dcdc converter (not shown)]. The battery/UC

also supplies power during acceleration because of sluggish FC

response. The H2

fuel is supplied from a tank, where it can

be stored as cryogenically cooled liquid or compressed gas.

H2 is usually generated from water using electricity from the

grid, or from environmentally clean source, such as wind, PV,

or nuclear. It can also be generated from coal through coal

gasification (integrated gasification combined cycle), where the

by-product CO2 gas is sequestered in underground storage, as

indicated. The O2 for the FC is obtained from air through a

compressor.

C. Bulk Energy Storage

As mentioned before, renewable energy sources, such as

wind and PV, are statistical in nature because of the depen-dence on weather conditions (and the time of the day) and


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therefore require storage of surplus energy to match with

the energy demand curve on the grid. As mentioned before,

to avoid expensive grid energy storage, the smart grid con-

cept can be used, where smart metering can condition the

demand curve (demand-side energy management) to match

with the available generation curve by offering lower tariff

rate.For example, EV battery charger, water heater, washer/dryer

loads, etc., can be shifted to off-peak hours, when electricity is

cheaper.

There are various methods of grid energy storage [19][22]

which can be briefly summarized as follows.

1) Pumped storage in hydroelectric plantIn this

method, hydrogenerators are used as motor pumps to

pump water from tail to head and store at high level

using the cheap off-peak grid energy. During the peak

demand, the head water runs the generators to supply

the demand. It is possibly the cheapest method of energy

storage but is applicable only with proper site facilities.

Otherwise, it may be expensive. The typical cycle en-

ergy efficiency may be 75%, and cost may be less than

$0.01/kWh. Currently, there is over 90 GW of pumped

storage facility around the world. A new concept in this

method is to use wind turbines or solar cells to directly

drive water pumps for energy storage.

2) Battery storageHistorically, this has been the most

common form of energy storage for the grid. In this

method, electrical energy from the grid is converted to dc

and stored in a battery. Then, the stored energy is retrieved

through the same converter system to feed the grid. Al-

though very convenient with high cycle efficiency (typi-

cally 90%), battery storage is possibly the most expensive(typically > $0.1/kWh). Leadacid battery has been usedextensively, but recently, NiCd, NaS, Li-ion, and flow

batteries (such as vanadium redox) are finding favor.

For example, General Electric (GE) installed 10-MVA

leadacid battery storage in the Southern California

Edison grid in 1988. The worlds largest battery storage

was installed by ABB in Fairbank, Alaska, in 2003 that

uses NiCd battery with a capacity of 27 MW for 15 min.

Flow batteries have fast response and can be more eco-

nomical in large-scale storage.

3) Flywheel (FW) storageIn FW storage, electrical en-

ergy from the grid is converted to mechanical energythrough a converter-fed drive system (operating in mo-

toring mode) that charges a FW, and then the energy is

recovered by the same drive system operating in gener-

ating mode. The FW can be placed in vacuum or in H2medium, and magnetic bearing can be used to reduce

the energy loss. Steel or composite material can be used

in FW to withstand high centrifugal force due to high

speed. FW storage is more economical ($0.05/kWh) and

has been used, but mechanical storage has the usual

disadvantages. Recently, wind turbines have been used

with direct coupling to FW system to achieve better

efficiency.

4) Superconducting magnet energy storage (SMES)Inthis method, grid energy is rectified to dc, which charges

SMES coil to store energy in magnetic form (1/2 L I2).

Then, energy is retrieved by the reverse process. The

coil is cooled cryogenically so that dissipation resistance

tends to be zero, and the energy can be stored indefinitely.

Either liquid helium (0 K) or high-temperature supercon-

ductor (HTS) in liquid nitrogen (77 K) can be used. The

cycle efficiency can be higher than 95%. SMES storage isyet very expensive.

5) UC storageA UC (also called supercapacitor or elec-

trical double layer capacitor) is an energy storage de-

vice like an electrolytic capacitor (EC), but its energy

storage density (Wh or 1/2 CV2/kg) can be as much as100 times higher than that of EC. UCs are available

with low-voltage rating (typically 2.5 V) and capacitor

values up to several thousand farads. The units can be

connected in seriesparallel for higher voltage and higher

capacitance values. However, the Wh/kg of UC is low

compared to that of a battery (typically 6 : 120 ratio for a

Li-ion battery). The power density (W/kg) of UC is very

high, and large amount of power can cycle through it (see

Fig. 5) without causing any deterioration. In the present

state of technology, UCs are yet expensive for bulk grid

energy storage.

6) Vehicle-to-grid (V2G) storageThis is somewhat a

new concept for bulk energy storage assuming that a

large number of battery EVs are plugged in the grid.

A plugged-in EV can sell electricity to the grid during

peak demand and then charge the battery during off-peak

hours. V2G technology can be used, turning each vehicle

with its 2050-kWh battery pack into a distributed load-

balancing device or emergency power source. However,

the main disadvantage is that the battery life is shortenedby chargedischarge cycles.

7) H2 gas storageH2 gas can be used as bulk energy

storage medium and then used in FC or burned as a

fuel in IC engine. This idea has generated the recent

concept of hydrogen economy, i.e., H2 as the future clean

energy source. As mentioned before, H2 can be gener-

ated easily from abundantly available sporadic sources

like wind and PV and stored as compressed or lique-

fied gas with high density amassable fuel. Of course,

it can be generated also from hydrocarbon fuels with

underground sequestration of undesirable CO2 gas. Bulk

H2 production using biomass and its underground stor-age in caverns, salt domes, and depleted oil and gas

fields are now being investigated. The overall energy

efficiency of H2 storage cycle may be 50% to 60%,

which is lower than that of battery or pumped storage

systems.

8) Compressed air energy storage (CAES)CAES is

another grid energy storage method, where off-peak or

renewably generated electricity is used to compress air

and store underground. When electricity demand is high,

the compressed air is heated with a small amount of

natural gas and then burned in turboexpanders to generate

electricity. CAES system has been used in Europe. The

idea of using wind turbines to compress air directly isfloating around.


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Fig. 6. Comparison of battery EV with FC EV (300-mi range).

D. Electric/Hybrid Electric Vehicle Scenario

Petroleum fuel price increase and environmental (particu-

larly urban) pollution control are the main motivations for

worldwide R&D activities in EV/HEV for more than the last

three decades. In an EV, generally, battery is the energy storage

device. The dc is converted to variable-frequency variable-

voltage ac to drive an ac motor (induction or synchronous).

The braking energy can easily be regenerated to recharge the

battery. In a HEV, battery is the energy storage device. This

is assisted by a power device which is usually a gasoline IC

engine. While range is the main problem in pure EV, there is nosuch problem in HEV. The power electronics and motor drive

technology for EV/HEV is somewhat mature with reasonably

low cost. Unfortunately, however, todays battery technology is

not yet mature in spite of prolonged R&D. It is expensive and

bulky with large weight and has limited cycle life, and charging

takes several hours. Although Nimetal hydride (MH) batteries

are extensively used, recently, Li-ion batteries have penetrated

in the market. The latter has more than twice the storage density

than the former but is twice expensive. It appears that Li-ion (or

Li based) is the battery of the future, and currently, there is large

emphasis for its research in the USA. The HEVs will disappear

from the market when economical EVs with long range are

available.

Currently, a number of EVs and HEVs are commercially

available in the market. Among the HEVs, Toyota Prius II

(non-plug-in) with NiMH battery (1.2 kWh), gasoline engine

(57 kW), and interior permanent magnet synchronous motor

(IPMSM) drive (50 kW) is the most popular in the market with

an approximate price of $28 000. Soon, a plug-in version with

Li-ion battery will be introduced. Pure EV has a long history.

Currently, Tesla Roadstar in the USA sells EV (Li-ion battery,

215 kW, 3.5-h charging, and 245-mi range) at a price over

$100 000 to rich people. The battery life is typically 100 000 mi.

Some examples of recent introductions in the market are Nissan

Leaf and Chevy Volt, both of which use Li-ion battery. Leaf ispure EV (100-mi range) with a price of $32 780 of which the

battery cost is around $18 000. Volt is HEV (price of $40 280),

where the battery is charged by an ICE. In pure EV mode, its

range is only 40 mi but can extend to 360 mi with ICE charging.

More EVs/HEVs will be introduced in future.

E. Comparison of Battery EV With FC EV

Since R&D for both battery EV and FC EV are progressing

in parallel, it is worth making comparison between the two

technologies. Fig. 6 summarizes this comparison [23] in todays

technology for mass production with identical 300-mi range

and assuming that both deliver 60 kWh to the wheels. The

battery EV is assumed to have the battery charging from clean

wind energy (although, currently, it is mostly from coal or

nuclear), which is required to supply 79 kWh with a power

line efficiency of 92%, battery charging efficiency of 89%,

battery efficiency of 94%, and drive train efficiency of 89%,

as indicated in the figure. Typically, 6 kWh of regenerated

energy has been considered in this calculation. The total energy

efficiency of battery EV is calculated as 68%. The estimated

cost of the vehicle is $20 000 with battery cost of $0.16/W and

$250/kWh. The FC EV is also assumed to have primary energy

from wind turbines.

Considering all the efficiency figures of FC-EV line, the totalenergy efficiency is only 30%, i.e., 202 kWh is to be supplied

from wind turbines. Note that auxiliary storage of FC EV has

been ignored for simplicity. The corresponding cost figures

for FC EV are indicated in the figure. In summary, FC EV is

38% less efficient, has 43% more weight, and is 50% more

expensive. Considering the disadvantages, FC-EV research has

recently been backed down in the USA.

V. SOM E EXAMPLE APPLICATIONS

A. HVDC System for Wind Park Interconnection

Wind power can be available either from onshore or off-shore installations, where a cluster of wind turbine generator


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Fig. 7. HVDC system with voltage-fed two-level IGBT converters for off-shore wind park interconnection (simplified diagram) (ABB HVDC LightNordE.ON 1).

units (called wind farm or park) pool the power together and

then are interconnected to the grid. Generally, wind parks are

located away from load centers and therefore require high-

voltage transmission before connecting to the grid. A number

of wind power systems with HV transmission have been built

around the world. Fig. 7 shows the simplified diagram of

HVDC transmission system (NordE.ON1) [24] for the worlds

largest offshore wind park (450 MW) in the North Sea that is

interconnected to the German grid. It has been recently built

by ABB using HVDC Light technology, as indicated in the

figure. The wind park feeds ac power at the sending station,

where the voltage is boosted by a three-winding transformer(to supply auxiliary power), and feeds a back-to-back voltage-

fed PWM converter system (only the sending end is shown

in simplified form) before connecting to the ac grid at the

receiving station on the right. The intermediate double-circuit

HVdc transmission system at 150 kV is 200 km long (with

128 km undersea and 75 km underground). The cable trans-

mission has the usual advantages of better efficiency, less cost,

and absence of visual effect and the harmful effects of electric

and magnetic fields compared to overhead transmission. Each

converter unit is a three-phase two-level PWM voltage-fed

IGBT module converter (only half-bridge is shown), where a

large number of matched high-voltage devices (4.5 kV) areconnected in seriesparallel (multichip wafer) to share the large

voltage and power. Note that multilevel converters and IGCT

devices (invented by ABB) are not used in the installation.

Although IGBT conduction drop is higher, it has the advantages

of continuous current limiting, higher switching frequency

(2.0 kHz in this case), and faster turn-on and turnoff capability

to force the proper voltage and current sharing during switch-

ing. The voltage-fed converter system has the usual advantages

of multiterminal capability, control of active (P) and reactive

(Q) power independently, and mitigation of flicker or grid

voltage instability by fast Q control. In the absence of P, either

sides can be used as a STATCOM. The three-winding power

transformer uses on-load tap changing to maintain the convertervoltage maximum irrespective of supply voltage variation. The

converter uses sinusoidal PWM with zero sequence injection to

maintain maximum modulation index so that the dc voltage is

maximum and efficiency and power can be maximum. There

are a number of such HVdc-based wind park installations

around the world. Siemens uses such system (HVDC PLUS)

using IGBT-based multilevel converters [25].

B. FACTS for P and Q Control

The real (P) and the reactive (Q) power of a transmission

system can be controlled by power electronics-based FACTS.

The basic power electronic unit of FACTS is STATCOM, which

is a solid-state version of a rotating synchronous condenser. The

traditional STATCOM uses thyristor-controlled reactor with

parallel capacitor and thyristor-switched capacitor-bank-type

static VAR compensator (SVC). In recent years, high-power

STATCOMs have been developed using GTO-based multi-

level (three-level) voltage-fed converters and applied in utility

systems.

Fig. 8 shows the FACTS that has been recently installed

by Siemens for New York Power Authority (NYPA) [26].

The main diagram shows a transmission line with receiving

terminal and sending terminal along with the FACTS equipment

consisting of two STATCOMs (CONV-1 and CONV-2), and

the phasor diagrams explain their operation. Both the CONVs

are identical, and each consists of GTO-based three-level

48-stepped 100-MVA voltage-fed converter with capacitor on

the dc side and coupled to the line by means of a transformer as

shown. With the switch S open, CONV-1 is a shunt STATCOM

that can operate as three-phase variable capacitor or inductor,

as explained by the phasor diagrams (a) and (b) on the left.Therefore, CONV-1 alone can be used to control the sending

end bus voltage V3 or the flow of Q in the sending source.The CONV-2 injects series voltage Vi as a phasor so thatV2 = V3 + Vi. The phasor diagrams on the right indicate thatVi is aligned perpendicular to the line current I1 but subtractsand adds, respectively, from the sending terminal voltage V3.In (c), the current lags the injected voltage by 90, i.e., the line

current is reduced by equivalent series inductance effect. On

the other hand, in (d), the current leads the injected voltage

by 90, i.e., the line current is increased by equivalent series

capacitance effect. Note that, in either cases, CONV-2 controls

the P and Q of the line but does not require any input dc power(S is open). The universal-power-flow-control characteristics of

CONV-2 are explained by the phasor diagrams of (e), which

indicates that the arbitrary d and q component of voltage (within

the total limited magnitude of Vi) can be injected in series tocontrol P and Q independently. In such a case, real power has

to flow through CONV-2, as shown by the current Id on thedc side with the switch S closed. This means that CONV-1

supplies the real power VdId which is circulated in CONV-2,but in addition, it can control the Q flow independently. This

flexible P and Q control features in a segment of a transmission

system are extremely important. The transient response of the

STATCOMs to supply and absorb energy pulses is very fast,

and therefore, they can control transient stability and generatoroscillation problems of the system.


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Fig. 10. Axial flux PMSM direct drive of EV with vector control.

direct drive applications, where the machine is coupled directlyon the mechanical system. For example, in EV/HEV applica-

tions, AFPM machines can be mounted on two or more wheels,

thus eliminating mechanical gears and differential which are

used in single radial machine drive system. This gives higher

efficiency, less weight, and improved reliability. For direct

drive, of course, the machine has the usual size and weight

penalty. For EV/HEV application, the drive should operate

in four quadrants with constant torque and field-weakening

modes. The stator disk of AFPM machine is usually toroidal

in shape with radially mounted winding coils in slots. The rotor

disk is annular with NdFeB magnets mounted on the surface.

The machine characteristics are similar to that of surface-PM

radial flux sinusoidal permanent magnet synchronous motor

(PMSM), but with higher torque or power density and improved

efficiency and reliability. The machine cogging torque is re-

duced by short-pitched trapezoidal magnets and slot magnetic

wedge. The latter increases stator inductance and helps in

enhancing the field-weakening region.

Fig. 10 shows an AFPM motor application for direct wheel

drive of EV [34], [35]. The picture of the motor mounted on

the EV wheel is shown on the top right. The drive system

uses direct vector control with stator flux orientation. The

machine has small armature reaction effect and therefore op-

erates at nearly constant flux in efficiency-optimized lookup

table on torquespeed curves (which are a function of dclink voltage Vd), shown on the upper left. Ideally, these data

permit satisfactory operation in constant torque as well as infield-weakening regions with current control mode. In constant

torque region, Te = f(iqs), whereas in field-weakening region,Te = f(iqs, ids). The iqs and ids current control (called syn-chronous or dc current control) loops generate the respective

voltage commands (vqs and vds) through proportional-integral(P-I) regulators, which are added with the feedforward counter

electromotive force signals to enhance the close loop responses.

These voltages are then vector rotated, converted to three

phases, and fed to the inverter that uses space-vector PWM

(SVM). The lower portion of the figure shows the modulation

index (M) control to prevent saturation to square-wave mode

and compensate motor parameter variation effect. The ideal M

and actual M are calculated and controlled in close loop manner

by injecting ids with the lookup table generated ids, as shownin the figure. Standard symbols are used in the figure [3].

VI. CONCLUSION AND FUTURE SCENARIO

This paper gives a comprehensive review of the worlds

energy scenario and the climate change problems due to man-

made fossil fuel burning along with the possible mitigation

methods. Then, it discusses the growing impact of power

electronics on energy saving, renewable energy systems, bulk

storage of energy, and electric/hybrid vehicles in the 21st cen-

tury, in addition to the general trends of global industrialization.Finally, several example applications are described.


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Power electronics has now been established as a major

discipline in electrical engineering, and with the maturing trend

of the technology, the 21st century will find tremendous em-

phasis on applications, applications and applications. It is now

tending to merge as a high tech frontier in the classical power

engineering domain. For so long, power electronics engineers

have been very proud of their profession, but eventually, theywill lose their identity and be identified as power engineers.

It appears that the role of power electronics in our society in

the future will be as important and versatile as computers and

information technology today, if not more. In fact, computers,

information technology, power electronics, and power systems

will tend to merge to eventually emerge as a complex interdis-

ciplinary technology. This trend is being evident by the new

emergence of smart grid technology. Power electronics will

eventually be an important element in the industrialization and

energy policies of different nations of the world.

What is the future scenario in power electronics technology?

As the technology is maturing in recent years, we expect to

see increasing emphasis on incremental application-oriented

R&D in modularization, modeling, system analysis, simulation,

design, and experimental evaluations. This trend is already

evident in the recent conference and journal publications. In

general, some advances and trends of power electronics can

be summarized as follows. In power semiconductor devices,

IGBT has now emerged as the dominant device in medium to

high-power applications, whereas power MOSFET has become

universal in low-power high-frequency applications. The IGCT

is tending to lose the race with IGBT in the high-power area.

Silicon-based bipolar junction transistor and GTO devices are

already obsolete, and phase-controlled thyristors show the trend

of obsolescence in the future. Large bandgap devices (such asSiC, GaN, and thin-film diamond in the long run) are expected

to bring renaissance in power electronics, particularly in high

power for drives and utility system applications [37]. SiC-based

Schottky barrier diodes (1200 V, 50 A) and power MOSFET

half bridges (1200 V, 100 A) with bypass diodes are already

available in the market. In fact, SiC MOSFETS with voltage

rating up to 6 kV, when available, will wipe out most of the

silicon-based power devices from the market. High-voltage

high-power SiC MOSFET (up to 10 kV), IGBT (up to 25 kV),

GTO (up to 40 kV), junction barrier Schottky (JBS), and

p-i-n diodes (up to 10 kV) are yet in laboratory, and their

emergence will create significant impact in high-power appli-cations. Attempts are now being made to replace high-power

bulky 60-Hz transformer by solid-state high-frequency-link

power transformer using SiC power devices [12]. GaN-on-Si

power devices have all the advantages of SiC devices but show

significant potential for cost reduction.

Power quality and lagging displacement power factor (DPF)

problems are making the phase-controlled classical power elec-

tronics obsolete, promoting the active PWM line-side convert-

ers. Of course, AHFs and static VAR compensators tend to

mitigate these problems. In the authors view, AHF will tend to

be obsolete in the future. Among all the classes of converters,

the voltage-fed class is becoming universal, replacing the pre-

sent current-fed and cycloconverter classes. Multilevel (particu-larly the three-level diode-clamped type) voltage-fed converters

are showing increasing popularity in high-voltage high-power

utility systems and drive applications. Cascaded H-bridge

(CHB) or half-bridge topology has the advantage of modularity

and fault-tolerant applications. Traditional matrix converters

have been on and off many times since its invention in the

1980s, and in the authors view, its future promise appears to be

low. SVM is being increasingly popular over sinusoidal PWM,and currently, there is a trend of SVM algorithm simplification

for multilevel converters. Evidently, soft-switched converters

for motor drives and other high-power applications have lost

the promise except for high-frequency-link applications. The

future emphasis on converters will be mainly on modularization

and system integrationsimilar to the trend of very large scale

integration technology. Evidently, power electronics will play

an important role in the smart grid, as mentioned before. With

the dominance of distributed renewable energy sources and

bulk energy storage devices, maintenance of system frequency

and bus voltages with optimum resource utilization, economical

electricity supply to consumers, high system energy efficiency,

high system reliability, and fault-tolerant operation will require

extensive system studies [39]. Electrical machines and drives,

although practically a mature technology, incremental research

will continue on performance optimization, precision parameter

estimation and fault diagnosis for fault-tolerant control. With

rising energy cost, PMSMs (with NdFeB magnet) will find

increasing acceptance, although they are more expensive than

induction machines. In particular, IPMSM is more attractive for

large field-weakening applications. If magnet cost is sufficiently

low, PMSMs will dominate over induction motors in general

industrial applications. Unfortunately, at present, China (which

is the major source of NdFeB magnet, controlling 97% of the

world supply) is restricting the world market supply and raisingthe price. Axial flux PMSM will find application in direct drive,

particularly for electric vehicle and wind generation system.

Again, for high-power applications, wound-field SMs remain

popular. In the authors view, switched-reluctance-motor drives

do not show any future promise in the majority of applications

and have the clear trend of obsolescence. The majority of

electrical machines will have converters in the front end in

the present trend of decreasing converter cost, and integrated

machine-converter-controller (particularly in the lower end of

power) remains a clear trend. Among all the drive control tech-

niques, the scalar control techniques (including DTC control)

will be obsolete, and vector control will emerge as the universalcontroller. The cost differential in the complex vector drive

and simple scalar control is hardly noticeable because only the

software is more complex in the former, whereas the control

hardware essentially remains the same. MATLAB/Simulink-

based simulation, particularly real-time simulation with hard-

ware in the loop, is getting more emphasis. Although sensorless

vector drive is already available commercially, near-zero-speed

(or zero-frequency) precision speed or position estimation re-

mains a challenge because of the need for machine saliency,

complex signal processing with externally injected signal, and

parameter variation problem. The estimation is more complex

for induction machines compared to PMSM (which has built-

in saliency). However, zero-frequency sensorless PMSM driveshave been commercialized recently. With the present trend of


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DSP and field programmable gate array (FPGA) [or application

specific integrated circuit (ASIC)], a single chip control of

sensorless vector drive with fault-tolerant control is not far

away. As artificial intelligence (AI) technology matures, in-

telligent control and estimation (particularly based on neural

networks) will find increasing acceptance in power electronics,

particularly in the robust control of drives. With the matur-ing DSP and FPGA technologies, predictive control of power

electronic systems based on plant model and system variables

with well-known developed theory is showing a comeback for

enhanced system performance [47], [48]. Finally, R&D in FCs,

PV cells, batteries, passive circuit components, HTS, DSPs,

and ASIC chips, although does not fall in the mainstream of

power electronics, will significantly impact power electronics

evolution in this century.

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Bimal K. Bose (S59M60SM78F89LF96)received the B.E. degree from Bengal EngineeringCollege (currently the Bengal Engineering and Sci-ence University) (BESU), Calcutta, India, in 1956,the M.S. degree from the University of Wisconsin,Madison, in 1960, and the Ph.D. degree fromCalcutta University, Calcutta, in 1966.

He held the Condra Chair of Excellence (Endowed

Chair Professor) in Power Electronics at the Uni-versity of Tennessee, Knoxville (19872002), wherehe was responsible for teaching and research pro-

gram in power electronics. Concurrently, he served as Distinguished Scientist(19892000) and Chief Scientist (19871989) of Electric Power ResearchInstitutePower Electronics Applications Center, Knoxville. Prior to this,he was a Research Engineer in the General Electric Corporate Researchand Development (now GE Global Research Center), Schenectady, NY, for11 years (19761987), an Associate Professor of Electrical Engineering withRensselaer Polytechnic Institute, Troy, NY, for five years (19711976), anda faculty member at BESU for 11 years (19601971). He is specialized inpower electronics and motor drives, specially including power converters,PWM techniques, microcomputer/DSP control, electric/hybrid vehicle drives,renewable energy systems, and artificial intelligence (expert system, fuzzylogic, and neural network) applications in power electronics and motor drives.He has been a power electronics consultant in a large number of industries.He holds an Honorary Professorship in Shanghai University (1991), the

China University of Mining and Technology (1996), Xian Mining University(1998), and the Huazhong University of Science and Technology (2003).He has authored/edited seven books in power electronics: Power Electronicsand Motor DrivesAdvances and Trends (Academic Press, 2006), ModernPower Electronics and AC Drives (Prentice Hall, 2002), Power Electronics

and AC Drives (Prentice Hall, 1986), Power Electronics and Variable Fre-quency Drives (Wiley/IEEE Press, 1997), Modern Power Electronics (IEEEPress, 1992), Microcomputer Control of Power Electronics and Drives (IEEEPress, 1987), and Adjustable Speed AC Drive Systems (IEEE Press, 1981).He has given tutorials, keynote presentations, and invited seminars exten-sively throughout the world, particularly in IEEE-sponsored programs andconferences. He has authored more than 250 papers and is the holder of21 U.S. patents.

Dr. Bose is a recipient of a number of awards, including the IEEE PowerElectronics Society Newell Award (2005), IEEE Millennium Medal (2000),IEEE Meritorius Achievement Award in Continuing Education (1997), IEEELamme Medal (1996), IEEE Industrial Electronics Society (IES) EugeneMittelmann Award (for lifetime achievement in power electronics and motordrives) (1994), IEEE Region 3 Outstanding Engineer Award (1994), IEEEIndustry Applications Society (IAS) Outstanding Achievement Award (1993),Calcutta University Mouat Gold Medal (1970), GE Silver Patent Medal (1986),GE Publication Award (1985), and a number of IEEE prize paper awards.He also received the Distinguished Alumnus Award (2006) from BESU. Hehas served the IEEE in various capacities, including Chairman of the IESPower Electronics Council, Associate Editor of the I EEE TRANSACTIONSON INDUSTRIAL ELECTRONICS, IEEE-Annual Conference of IEEE IndustrialElectronics Society Power Electronics Chairman, Chairman of the IAS Indus-trial Power Converter Committee, IAS member of the Neural Network Council,Vice-Chair of the IEEE Medals Council, member of IEEE-USA Energy PolicyCommittee, member of the IEEE Fellow Committee, member of Lamme Medal

Committee, member of IEEE Power Engineering Medal Committee, memberof IEEE Awards Board, etc. He has served as a Distinguished Lecturer ofboth the IAS and IES. IEEE IES Magazine published a special issue (June2009) Honoring Dr. Bimal Bose and Celebrating His Contributions in Power

Electronics.

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