Electrical and Electronics Engineering: An International Journal (ELELIJ) Vol 2, No 2, May 2013
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A BATTERY CHARGING SYSTEM & APPENDED ZCS
(PWM) RESONANT CONVERTER DC-DC BUCK: TECHNIQUE FOR BATTERY CHARGER TO YIELD
EFFICIENT PERFORMANCE IN CHARGING SHAPING
IrfanJamil*1, Zhao Jinquan
2, Rehan Jamil
3, Rizwan Jamil
4and Abdus Samee
5
1,2Department of Energy & Electrical Engineering, Hohai University, Nanjing, China
[email protected]
3School of Physics & Electronic Information, Yunnan Normal University, China
[email protected]
4Heavy Mechanical Complex (HMC-3) Taxila, Rawalpindi, Pakistan
[email protected]
5Chashma Centre of Nuclear Training, PAEC, Pakistan
[email protected]
ABSTRACT
This paper presents technique for battery charger to achieve efficient performance in charging shaping,
minimum low switching losses and reduction in circuit volume .The operation of circuit charger is switched
with the technique of zero-current-switching, resonant components and append the topology of dc-dc buck.
The proposed novel dc-dc battery charger has advantages with the simplicity, low cost, high efficiency and
with the behaviour of easy control under the ZCS condition accordingly reducing the switching losses. The
detailed study of operating principle and design consideration is performed. A short survey of battery
charging system, capacity demand & its topologies is also presented. In order to compute LC resonant pair
values in conventional converter, the method of characteristic curve is used and electric function equations
are derived from the prototype configuration. The efficient performance of charging shaping is confirmed
through the practical examines and verification of the results is revealed by the MATLAB simulation. The
efficiency is ensured about 89% which is substantially considered being satisfactory performance as
achieved in this paper.
KEYWORDS
ZCS, PWM Resonant Converter, dc-dc Buck, Battery Charger
1. INTRODUCTION
In recent years, with the enhancement of power electronics technology and control strategies in
power electronics devices coupled with the increasing demand of high efficiency in battery
charger system has invoked enormous attention from the research scholars around the world.
Battery charger system technology is currently being incorporated in urban industrial areas to
maintain with these demands lot of work is on towards. Therefore, many battery chargers with
different ratings and functionalities are being developed for high output efficiency since few
Electrical and Electronics Engineering: An International Journal (ELELIJ) Vol 2, No 2, May 2013
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years. The battery charger usually works to globalize the energy saving and to serve in fast
transportation systems. The use of battery charger brings convince life solution during the
traveling from urban to rural areas. Many techniques were fetched out by the scientists since
battery charger device was developed for renewable energy generation, electronic communication
power supplies, electric vehicles, UPS or an uninterruptible power supplies, PV systems and
portable electronics products. Many charging methods have been developed to improve the
battery charger efficiency in the last few decades. In order to achieving high efficiency in battery
charger, append the traditional battery charger with the technique of ZCS ( Zero-Current-
Switching) resonant buck topology which delivered the efficient performance in charging
shaping[11-12-13-14].
This work looks at the issues which associates ZCS PWM (Zero-Current-Switching Pulse width
Modulation) converter, buck topology with the battery charger. This paper develops a novel high-
efficiency battery charger with ZCS PWM buck topology which has simple circuit structure, low
switching losses, easy control and high charging efficiencies [1-3]. Zero Current Switching
resonant buck converter is analyzed and mode of operation is also studied. Various waveforms &
charging curve period were noted down during the piratical examine using MATLAB software.
The curve of charging efficiency during the charging period shows 89% charging output
efficiency of novel proposed prototype.
Fig.1 Block Diagram for the Proposed Novel Battery Charger
2. BATTERY CHARGERING SYSTEM & CAPACITY DEMAND
Todays most modern electrical appliances receive their power directly right away the utility grid.
Many devices are being developed everyday which requires electrical power from the batteries in
order to achieve large mobility and greater convenience.
The battery charger system utilizes the battery by working to recharge the battery when its energy
has been drained. The uses rechargeable batteries include everything from low-power cell phones
to high-power industrial fork lifts, and other construction equipment. Many of these products are
used everyday around-the-clock commonly in offices, schools, and universities, urban and
Electrical and Electronics Engineering: An International Journal (ELELIJ) Vol 2, No 2, May 2013
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civilian areas [8-9]. In fig. 2 shows that the Battery Capacities of Various Battery-Powered
Devices which are used in different rate of watt per hours level in cell phones, laptops, power
tools, forklifts and golf crafts etc.[10].
Fig.2 Battery Capacities of Various Battery-Powered Devices
A battery charger system is a system which uses energy drawn from the grid, stores it in an
electric battery, and releases it to power device. While engineers are used modern techniques to
usually design the battery charger systems, which maximize the energy efficiency of their devices
to make certain long functioning & operation time between charging; however they often neglect
how much energy is used in the conversion process of ac electrical power into dc electrical power
stored in the battery from the utility grid.
Apparently, energy savings can be possible if the conversion losses are reduced which associated
with the charging batteries in battery-powered products & output voltage can be controlled via
switching frequency. We can achieve these savings using different techniques including
battery charger topology that is readily available today and is being employed in existing
products. The same technique and topology is discussed in this paper which increases the
efficient performance in charging shaping of novel battery charger.
Electrical and Electronics Engineering: An International Journal (ELELIJ) Vol 2, No 2, May 2013
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Fig.3Structure of a multi- piece battery charger system. The efficiency calculation is made over a
24 hour charge and maintenance period and a 0.2C discharge for the battery. (Prepared for
California Energy Commission Contract by EPRI Solution Ltd.,) [10].
3. METHODS OF BATTERY CHARGING SYSTEM & ITS TOPOLOGIES
Methods of efficiency improvements in battery charger systems in use today have substantially
lower possibilities due to a lack of cognitive skills in the charger and battery which commonly
consume more electricity than the product they power. The energy savings are achieved in
millions of battery charger systems that are presently in operation worldwide by reducing
inefficiencies in charger and battery. Battery charger systems work in three modes of operation.
In charge mode of operation, the battery is accumulating the charge while the maintenance mode
of operation occurs when battery is fully charged and charger is only started to supply energy to
undermine the natural discharge. No-battery mode of operation shows that the battery has been
physically disconnected from the charger [8-9].
Fig.4SwitchModeBatteryChargerPowerVisibility
Electrical and Electronics Engineering: An International Journal (ELELIJ) Vol 2, No 2, May 2013
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There are lots of methods which are recognized to achieve the higher efficiency in battery charger
systems, including:
Higher voltage systems
Switch mode power supplies
Synchronous rectification
Improved semiconductor switches
Lithium-ion batteries
Charge and discharge at lower current rate
Off-grid charger when no battery is present.
Topologies
Normal
Efficiency
Range(%)
Estimated
Improved
Efficiency
Range (%)
Switch Mode
40%- 60%
50%- 70%
SCR
30%- 55%
45%- 60%
Ferro resonant
25%-50%
45%-55%
Linear
2%- 30%
20%- 40%
TABLE: 1 Efficiency improvements in charger topologies
Table.1 show that the efficiencies of normal and improved range are measured less than 15%,
comparable systems with overall efficiencies of 65% or greater are technically feasible in charger
topologies for battery charger system. The linear and switch mode chargers are analogous to
linear and switch mode power supplies with the exception that the charger topologies also
incorporate charge control circuitry on their outputs. Most multi- or single-piece chargers are
either linear or switch mode chargers. These two categories are found commonly in consumer
applications, particularly in the residential pub
