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New Analog IC Technology Support Safety, High Efficiency and High Reliability

of Today's PV Solar System

Delivering MORE Together

• Shanghai International Power Electronics Innovation Forum, 21, 2012

Picture: 53MW solar park, Lieberose, Germany

Solar Magic

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Agenda

• Challenges of Today’s PV Solar Industry Development

• PV Solar Market Ask for Safe System, Arc Detection

• Distributed MPPT Increase Solar Power Harvest, DC/DC Optimizer

• New SBD Raise the Reliability of PV Panel

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Big Trend – the 3rd Wave of Electronics

• 1st Wave - Essential Electric Society

– Home appliances, Ice box, Washer, TV, etc.

– Wired telecom

– Incentive to more electrical energy consumption

• 2nd Wave - Informative and Network Society

– PCs are every where and

– Mobile telecom & Internet access

– Encourage energy conservation

• 3rd Wave – Smart & Environment Protection Society

– WW population up to 7B (China 1.6B), a new challenge to energy resource

– Solar Power is the best solution among all the renewable energy

– PV Solar bring in new opportunities for all the industry including ICs

Hi Growth Rate, Huge Market Potential

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AP and China Solar Installation Market is Soaring

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PV System & Ecosystem

Smart

Jbox

SM

PCBa

SM Chip

Set

TI solar ref

•Safety is a strong demand of future PV solar systems

•High total system efficiency bring attention from $/Wp to $/KWh of ROI

•Reliability is system engineering over total PV system

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New 2011 NEC Arc-Fault Requirements for PV Systems

Article 690.11 Mandate

• Written to detect and interrupt “series” arc-faults in

modules, connections, wiring, and other

components in a PV System

• Requires inverters, charge controllers or other

devices in the arcing circuit to be disconnected and

disabled

• Requires manual resets and reconnects once an

arc is detected and fixed

• Functionality tested according to UL 1699B

• TI-SVA is full member of the UL workgroup

defining this standard

The new 2011 NEC

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Arc Detection Solution

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• SM73201 Arc-Detection compliant with NEC requirements

• Detects series, parallel and ground fault arcs

• Check frequency for arc detection up to 20Hz.

• Arc detect signal can be output as a digital output or over UART or

wireless signal.

• Designed to operate in the presence of noise due to switching power electronics (inverters, power optimizers, etc…). Special algorithms designed to recognize these signals and avoid false triggers.

• Tested for all major inverters/PV technologies

• Available for integration into

– Smart combiner box, Decentralized PVI (up to 15 A)

– Multi-string Option

– Self-Test Feature

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Arc Detection Principle Block Diagram

DC

Po

wer

Lin

e

Electrical Parameters SM73201-ARC-EV

String current 15A

Multi-string Option Yes

DC Bus Voltage 1000V (3000 V iso)

Arc Detection Time <150 ms

The arc detection signal

can be used in various

configurations to trigger

the shut-down of the

affected module or string:

-Electro-mechanical

string shut down

- Inverter based shut-

down

Multi-band

Dynamic

Filtering

DSP

SM73307

SM73308C2000SM73201

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Arc Detection Main Features

• Check frequency for arc detection up to 20Hz.

• Arc detect signal can be output as a digital output or over UART or

wireless signal.

• Designed to detect parallel and serial arcs

• Designed to operate in the presence of noise due to switching power

electronics (inverters, power optimizers, etc…). Special algorithms

designed to recognize these signals and avoid false triggers.

• The arc detection circuitry has been designed to pass the draft standard

for arc detection being developed by the UL1699B working group.

• Arc detect reference design operates in single and multi string

architectures

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Arc Protection/Remote Shutdown

Arc Detect configuration

Approximate board area

for arc detection: 50x30

mm

Arc Detection Reference PCBoard SM73201-ARC-EV

Support:http://www.national.com/rd/RDhtml/RD-195.html

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Arc Detection Evaluation Board SM73201-ARC-EV

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Approximate board area

for arc detection: 50x30

mm

Reference design

samples available *User’s Guide available

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DC Arc Characteristics

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DC Arc Characteristics – Inverter ON

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Try Detecting the Arc Now!

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UL Arc Detection Test Procedure UL 1699B (Draft)

Source: UL 1699B DRAFT

OUTLINE OF INVESTIGATION FOR

PHOTOVOLTAIC (PV) DC ARC-FAULT CIRCUIT PROTECTION

Version December 16, 2010

National Semiconductor (merged to SVA/TI) is a full member of the UL

working group that defines this standard

Arc generator Small tuft of steel wool placed inside tube

Arc Generator

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SolarMagicTM

DC/DC Power OptimizerTechnology & IC Products

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Distributed MPPT - Higher Efficiency

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•Solar Plant / Utility

•Commercial Facilities

• BIPV / Solar Wall

• BAPV

• Public facilities

•Residential Rooftop

• Grid-tied solar system

• Off-grid solar home w/ energy storage

• Solar home system w/ energy storage by on-grid

supply

•Extended Solar Applications

• Small solar system w/ energy storage

• Mobile solar backup power

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SolarMagic DC/DC Optimizer Chipsets

• Enables power optimizing solutions for Off-Grid and Grid-Tied solar

systems

• Wide voltage input range that makes compatible with most of

commercially available solar panels (100V)

• Current driving capabilities up to 100A

• Advanced protection features (OVP,OCP and OTP)

• I2C programmability allows high degree of customization

• 125°C operation

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Reference DesignsGrid-Tied SM1230/SM3320 Chipset

NSID Description Package SM1230 SM3320

SM72485 150mA, 100V Constant On-Time Buck Switching Regulator LLP-8 X X

SM72238 100mA, 5V Micropower Voltage Regulator TO-252-3 X X

SM72240 uP Reset Circuit, Active-Low Reset Open Drain Output SOT-23-5 X X

SM72295 Full Bridge Driver SOIC-8 X X

SM72441 MPPT Controller with OVP, OCP, and OTP TSSOP-28 X

SM72442Enhanced MPPT Controller with Panel Mode, OVP, OCP, and

OTPTSSOP-28 X

SM72480 +/- 2.2C Thermostat, 120C Trip LLP-6 X X

SM72501 Precision, CMOS Input, RRIO, Wide Range Amplifier SOT-23-5 X X

SM72375Dual Micropower RRI CMOS Comparator with Open Drain

OutputMSOP-8 X

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Technical Support• Chipset of SM3320 SM72442 MPPT Controller w/ I2C

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• Panel voltage reading

• Panel current reading

• Battery voltage reading

• Battery current reading

• Output voltage set-point adjustments

• Open loop mode: duty cycle can be

controlled directly through I2C

• Dead time control

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Technical Support• Chipset of SM3320 SM72295 Dual Half Bridge Driver

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• Dual Half Bridge MOSFET

Drivers

• Integrated 100V bootstrap

diodes

• Independent High and Low

driver logic inputs

• Bootstrap supply voltage

range up to 115V DC

• Two current sense

amplifiers

with externally

programmable gain and

buffered outputs

• Programmable over voltage

protection

• Supply rail under-voltage

lockouts with power good

indicator

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SolarMagic SM3320 Benefits

• PV Design Flexibility

• Integrated, easy installation

• Varying string lengths

• Different roof orientations per string

• Increases roof coverage

• Scalable

• One solution fits all - from residential through commercial

• Lower cost per kWh

• Enables lower balance of system costs, installation/design time

• Support on/off –grid PV solar system with Energy Storage

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SolarMagic Proven Performance

• Various entities (both National and third parties) have done extensive

testing and experiments on the SolarMagic technology

• Results from both National’s internal tests and customer case studies

show a significant performance increase when the technology is in

use:

– Recovery of lost energy - up to 75%

– Additional energy harvest - up to 25%

• Testing by outside agencies (Photon, NREL, others) show significant

performance numbers when SolarMagic assisted strings are tested in

parallel against unassisted strings:

– Recovery of lost energy - up to 71%

– Additional energy harvest - up to 39%

More Energy for System Owner!

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0

10

20

30

40

50

60

70

80Energy With SolarMagic (kWhr)

Energy Without SolarMagic (kWhr)

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Source: various field trials and outdoor tests

SolarMagic Performance Results

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Value Created by SM3320

• $3.50/Wp installed cost

• 10% installation savings

• 20% BOS (Racking, Wiring,

Combiner Box) savings

• 50% Engineering savings

• 17% Inverter savings

• >9% Energy harvest gain

over 25yrs

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Local Players are Taking Actions…

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Case 1: Multiple orientations in single stringTokyo, complex roof

• Layout String2:North,7panels

String3:

3West+3South

=6panels

w/ SolarMagic

String1:East, 7panels

Tilt: 30.1deg (6-sunn)

SuntechPower, 180W x20panels

=3.6kW system

Detailed analysis to

follow on pages

TI Information Selective Disclosure 26

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Case 2: Parallel strings with different lengths

• Situation created when rooftop size

limited.

• Different string lengths enables

maximization of output power

• Use Optimizer in shorter strings only

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Case 3: Shade with multiple string and single MPPT channel

• Shade should affect more than 15% of

modules in a particular string

• Hard shade: current flowing through

bypass diodes

• Optimizers only needed on shade

affected string.

• Best to use optimizers on all modules

in string

MPPT

TI Information Selective Disclosure 28

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Case 4: Soft-shade with single string

• Optimizer only needed on shaded

modules

Note: Soft shade does not force the bypass

diode to turn on!

In case of hard shade the bypass diode will

eliminate the potential of the optimizer to

compensate for mismatches of the operating

point between shaded and un-shaded

modules

TI Information Selective Disclosure 29

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SolarMagicTM

Smart Bypass Diode

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How Do By-Pass Diodes Work?

Continuous

Energy Loss

due to leakage

!

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Bypass Diode Replacement

Junction Box Junction Box

SBD

SBD

SBDControl

Circuitry

Smart Bypass

Diode

Module with

conventional

bypass diodes

Bypass diodes protect PV cells from reverse breakdown voltages

and prevent hotspots in PV cells

Problem: Bypass diodes themselves create significant amount of

heat

Solution: Smart bypass device which creates less heat

Junction Box

SBD

SBD

SBDControl

Circuitry

Smart Bypass

Diode

Module with

Smart bypass

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Smart Bypass Diode Thermal Advantage

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Measured at 10AMax 123º C Max 64º C

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Smart Bypass Diode Thermal Advantage

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Max 123º C

Max 64º C

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Thermal Evaluation

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Smart Bypass Switch Benefits

Reduced module cost

– Reduce heat sink in junction box, size of junction box

– Options for alternative packages

Enable higher current modules

– Eliminate need for heat-sinking especially at increased module efficiency

Increased reliability

– Module lifetime decreased by heat generated in junction box

– Reduce failure rate in the field Lower Levelized Cost of Energy (LCOE)

Improved Safety

– Reduced fire hazard

Higher energy yield

– Reduce reverse current leakage

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Electrical Specifications

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Standard Packaging TO263

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End of Document

Contact Information:

Johnson HuSolar, Analog Business DevelopmentTel: +86-21-23073736Johnson.Hu@ti.com

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Q&A

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问题之一

TI 的电弧检测方案可以用在光伏系统的哪些方面?

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问题之二

TI 的SolarMagic DC/DC 优化器的好处有哪些?

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问题之三

TI 的Smart Bypass Diode 有哪些特点?