Transcript Modeling of SMPS control system

TM
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, t
he Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore and Symphony
are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack,
ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a Package, Processor Expert, QorIQ
Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks
of Freescale Semiconductor, Inc. All other product or service names are the property
of their respective owners. © 2011 Freescale Semiconductor, Inc.
Agenda

Renewable energy a glance

Solar Photovoltaic System design evolution

Solar Cell its Characteristics, and control algorithm to optimize
energy harvest (MPP)

Common Solar Converter Requirements and safety algorithm

Solar Converter System Architectures and topology

Q&A
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Agenda

Renewable energy a glance

Solar Photovoltaic System design evolution

Solar Cell and its Characteristics and control algorithm to optimize
energy harvest (MPP).

Common Solar Converter Requirements and safety algorithm

Solar Converter System Architectures and topology
TM
3
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Renewable Energy
Renewable energy comes from natural resources such as sunlight,
wind, rain, tides, and geothermal heat, which are renewable (naturally
replenished).
– Renewable energy provides 19% of electricity generation
worldwide.
Mainstream forms of renewable energy:
Wind power:
Airflows can be used
to run wind turbines to
Generate electricity
TM
Solar PV:
Photovoltaics uses
solar radiation to
generate electricity
Hydropower:
Water steam, or
moderate sea swell,
can yield energy.
4
Biomass:
plant material uses
photosynthesis to
generate electricity
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Energy
“Solar energy technologies include solar heating, solar photovoltaics,
solar thermal electricity and solar architecture.”
Passive
solar techniques:

Orienting a building to the Sun

Materials with favorable thermal mass

Designing spaces that naturally circulate air
Active
solar techniques :

Solar thermal

Photovoltaic panels

A solar cell, or photovoltaic cell (PV), is a device that converts light into
electric current using the photoelectric effect.
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar photovoltaic systems

Solar Power Inverter

Grid Connected String Inverter

Grid connected Microinverter

Solar battery charger

Solar Lantern

Solar LED street light
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Converter Block Diagram
DC from solar
panel (s)
DC/DC
MPPT
Optional
Additional
DC/DC
Modules
For
multi-string
support
Inverter
DC/DC
MPPT
Optional
Transformer
Isolation
(safety)
VAC
Optional
Battery
Controller
DC/DC
MPPT
Optional
Battery
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Agenda

Renewable energy

Solar Photovoltaic System design evolution

Solar Cell and its Characteristics and control algorithm to optimize
energy harvest (MPP).

Common Solar Converter Requirements and safety algorithm

Solar Converter System Architectures and topology
TM
8
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Basic Solar Panel Construction
String 1
String 2
Module
Cell
Strings - Multiple Cells are connected together in series to raise
the output voltage.
Modules – Multiple Strings connected in parallel to raise the
output current.
Arrays – Multiple Modules connected in series and/or parallel to
raise output power
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Power Evolution:
The beginning
Log Cabin System – Simple 12 volt DC system providing lighting for isolated cabins. Low
wattage ( <100 W) solar panels connected directly to battery. Battery connected to lamps and
other 12 volt DC appliances.
Battery life compromised by unregulated charging. Limited appliances available for 12 volt
DC power. Wire resistance limits power to few hundred watts.
This system is not connected to the AC power lines (Off-Grid).
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Power Evolution:
Simple Inverters with battery charger
Note: series diode is often built into panel
Inverter
Charge
Controller
Country Home System – Larger panels providing 24 – 96 volts are connected to an
inverter to yield 120/240 VAC to operate standard lighting and appliances. Battery life
improved with regulated charging module. The higher DC voltages support moderate
power levels.
This system is not connected to the AC power lines (Off-Grid).
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Power Evolution:
Grid Connected Inverter
Inverter
Urban Home System – Larger panels providing 200 - 400 volts are connected to an
inverter to yield 120/240 VAC at medium power levels (2 -10KW)
This system is connected to the AC power lines (Grid-Tied). The customer sells power to
the power company during the day, buys power from the power company during the night.
Grid-Tied approach eliminates expensive and short lived batteries.
Issues: Inverter has potential as a single point failure. Non optimal power harvest from solar
panel especially in partial shading conditions.
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Power Evolution:
Individual DC/DC converters
DC/DC
DC/DC
Inverter
DC/DC
DC/DC
Single Inverter with multiple DC/DC Converters – The use of DC/DC converters per
string provide enhanced power harvest from solar panels. The DC/DC converters may be
separate modules or reside within the Inverter module.
This method is still susceptible to single point failure of inverter, and it involves the
distribution of high voltage DC power – A dangerous situation because direct current power
fusing is difficult to achieve.
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Power Evolution:
Grid Connected String Inverters
Inverter
Inverter
Inverter
Inverter
Urban Home System with String Inverters - Panels providing 200 - 400 volts are
connected to multiple inverters to yield 120/240 VAC at medium power levels (2 -10KW).
The inverters are connected to the Grid.
The use of multiple inverters provides enhanced power harvest from solar panels and
provide enhanced system reliability.
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Power Evolution:
Grid Connected MIC Inverters
Inverter
Inverter
Inverter
Inverter
Inverter
Inverter
Module incorporated Inverters (MIC) – Each solar panel module incorporates its own
inverter. MIC inverters are also known as “Micro Inverters”.
The incorporation of inverters into the solar panels greatly reduces installation labor costs,
improves safety, and maximizes the solar energy harvest.
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Converter Trends
1. Moving from centralized inverters to distributed inverters to
optimize energy harvest.
2. Incorporating converters into the solar panel modules to reduce
installation costs.
3. Improve system reliability from 5 to 20 years by reducing converter
temperatures, and removing Fans.
4. Replace Hard-Switching techniques with Soft-Switching to
improve efficiency and reduce heat dissipation.
5. Standardize designs (HW & SW) to improve reliability and reduce
costs. From cottage industry to mass production.
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Converter Trends, cont.
6. Eliminate electrolytic capacitors because of high failure rate.
Designs require higher voltages to reduce currents which allows use
of lower capacitance non electrolytic capacitors.
7. Grid-Tied converters eliminate the need for batteries n many
applications. Batteries are very expensive, require maintance, and
are short lived.
8. MIC (Module Incorporated Converters) converters tend to be lower
powered (few hundred watts) which tends to lower internal
temperatures and improve reliability.
9. The MIC Solar systems require many inverters to handle a specific
power level thus driving up production quantities which reduces
costs.
TM
17
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Agenda

Renewable energy

Solar Photovoltaic System design evolution

Solar Cell its Characteristics and control algorithm to optimize
energy harvest (MPP).

Common Solar Converter Requirements and safety algorithm

Solar Converter System Architectures and topology
TM
18
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Cell Characteristics
A solar cell is a current source, not a voltage source!
Io
Rs
Vo ~ 0.5 Volts
Rp
Vo
Io ~ 1 to 3 Amps
Simplified circuit model of a solar cell
Current is dependent on illumination, voltage more dependent on temperature.
Effective use of series connected solar cells depends on identical currents
being generated by each cell.
!!! It is not like stacking battery cells together !!!
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Cell Shading
String 1
String 2
Shaded Cell
Module
If a single cell in a string is shaded due to trees, dirt, clouds, bird
droppings, or is damaged, its current output will not match that of the
other cells.
Remember – current sources have high impedance.
The high current level of the un-shaded cells is forced thru the shaded
cell. A very large voltage drop is developed across the shaded cell (~10
volts). The energy harvest for the string can be reduced 50%. The
combination of large voltage drop and high current may damage the
shaded cell (Hot Spots).
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Cell – Bypass Diode
Adding a bypass diode protects solar cell in shaded
conditions by limiting voltage drop and it minimizes
associated power losses.
I
o
Rs
Vo
Rp
Solar cell with externally connected Bypass Diode
Adding a bypass diode adds cost for parts and labor.
Typically, one bypass diode per 18 solar cells is provided to prevent cell damage
when shaded.
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Cell – Characteristics
Solar cells output continually varies with LIGHT and TEMP
Maximum Power Point
Current
Current
3
G=1000 W/m2
3
2
G=600 W/m2
2
1
G=300 W/m2
Maximum Power Point
G=1000 W/m2
10°C
60°C
1
Voltage
Voltage
5
10
15
20
25
I-V versus Illumination (36 cell string)
5
10
15
20
25
I-V versus Temp (36 cell string)
Maximum Power Point Tracking Algorithm (MPPT)
•
•
Closed loop algorithm continually adjusts input V / I
to operate at the point of maximum power output
Requires 20-30 MIPS – typically DSCs/MCUs are used
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Cell –Maximum Power Point
Tracker (MPPT)
Power
Maximum Power Point
80 W
40 W
20 W
Voltage
5
10
15
20
25
P-V at constant illumination (36 cell string)
The MPPT algorithm constantly searches for optimum peak power point at
which to extract power from solar panel.
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Few Algorithms for MPPT

Perturb and Observe (P&O)

Three-point weight comparison method

Incremental Conductance Algorithm

Parasitic Capacitance

Constant Voltage Algorithm

Constant Current Algorithm …. And so on
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Control Loop – MPPT
Start
Set MPPT reference
Read Vpv, Ipv
PowerNew = Vpv*Ipv
Yes
PowerNew > PowerOld
MPPT ref+
(IAC Ref)
NO
PowerOld
PowerNew
MPPT ref(IAC Ref)
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Control Loop – MPPT
Maximum Power Point

PowerNew is continously monitor and
IACref is continuously modified to track
MPP point
Current
3.5
3
2
1

Small Change in IACref produce large
PV Voltage drop after MPP Current
point
10
20
30
40
50
10
20
30
40
50
150 W
Delta PV voltage checked at every
perturb event to keep current
reference close to MPP
Power

100 W
50 W

Perturb magnitude needs to modify to
stay at MPP and avoid oscillation
Voltage
TM
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Agenda

Renewable energy

Solar Photovoltaic System design evolution

Solar Cell and its Characteristics and control algorithm to optimize
energy harvest (MPP).

Common Solar Converter Requirements and safety algorithm

Solar Converter System Architectures and topology
TM
29
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Common Solar Converter Requirements
 MPPT – Maximum Power Point Tracking
algorithm required to optimize the power
harvest from solar panels.
 System efficiency > 94% (as high as possible)
 Wide DC input voltage range
 Cost < $0.50 per watt (production quantity)
 Safety – Fault detection, anti islanding
 AC Quality (THD<5%) – meet IEEE 519
TM
30
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Grid Over/Under Voltage/Frequency Protection
Per IEEE1547
Over Voltage1 fault
Over Voltage2 fault
> 110% for > 1 second
> 120% for > 160 ms
Under Voltage1 fault
Under Voltage2 fault
Over Frequency fault
Under Frequency fault
< 88% for > 2 seconds
< 50% for > 160 ms
> 60.5 Hz for > 160 ms
< 59.3 Hz for > 160 ms
Under Frequency fault < 57 Hz for > 160 ms
TM
31
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Anti Islanding – The detection of the
loss of connection to the GRID and the
removal of AC output power generation.
The purpose is to protect service
personnel from electric shock while they
work on a section of the GRID they
assume is un-powered.
TM
32
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
If battery backup is included in the
Solar PV system:
1. Optimize the battery charging rate over
temperature and state of charge to
maximize battery life.
2. Protect battery from excessive
discharge current rates to maximize
battery life and power production.
3. Protect battery from extreme discharge
(low voltage) to prevent battery damage.
TM
33
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Agenda

Renewable energy

Solar Photovoltaic System design evolution

Solar Cell and its Characteristics and control algorithm to optimize
energy harvest (MPP).

Common Solar Converter Requirements and safety algorithm

Solar Converter System Architectures and topology
TM
34
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Converter System Architectures
 Direct DC input to Inverter H-Bridge
Low cost but no isolation and narrow input voltage range
 Transformer coupled DC/DC to Inverter H-Bridge
Provides isolation but higher cost and lowered efficiency
 Boost DC/DC to Inverter H-Bridge
No isolation but low cost and wide input voltage range
TM
35
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Solar Inverter Output Configurations
 Single Phase
(typical appliance)
 Dual Single Phase
(typical U.S. home)
 Three Phase
(commercial, industrial)
TM
36
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Common Solar Inverter Topologies
 Voltage fed 3-Phase H-Bridge
Simple control but has high switching losses
 Current fed 3-Phase H-Bridge
Low voltage stress, simple control, high switching losses
 Resonant DC-Link 3-Phase H-Bridge
Low soft switching losses but higher voltage stress
 Active Clamped Resonant DC-Link 3-Phase
Low soft switching losses but higher complexity
 Quasi Resonant DC-Link 3-Phase
Low soft switching losses but higher complexity
TM
37
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
3- Phase Voltage Source Circuit
+
Q3
Q1
Q5
PWM2H
PWM1H
IGBT
PWM3H
IGBT
IGBT
Va
Vb
Vc
PWM2L
PWM1L
IGBT
-
Q2
TM
PWM3L
IGBT
IGBT
Q4
Q6
38
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
3- Phase Current Source Circuit
Q3
Q1
+
PWM1H
IGBT
Q5
PWM2H
PWM3H
IGBT
IGBT
V
a
Vb
Vc
PWM2L
PWM1L
IGBT
Q2
PWM3L
IGBT
IGBT
Q4
Q6
TM
39
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
3-Phase Resonant DC Link Circuit
+
Q3
Q1
PWM1H
IGBT
PWM2H
Q5
PWM3H
IGBT
IGBT
Va
Vb
Vc
PWM2L
PWM1L
IGBT
-
Q2
TM
PWM3L
IGBT
IGBT
Q4
40
Q6
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Active Clamp Resonant DC Link Circuit
+
Q3
Q1
PWM1H
IGBT
PWM2H
Q5
PWM3H
IGBT
IGBT
Va
Vb
Vc
PWM4
PWM2L
PWM1L
IGBT
-
Q2
TM
PWM3L
IGBT
Q4
41
IGBT
Q6
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Quasi- Resonant 3-Phase Circuit
+
Q3
Q1
PWM1H
IGBT
PWM4
PWM2H
Q5
PWM3H
IGBT
IGBT
Va
Vb
Vc
PWM5
IGBT
PWM2L
PWM1L
IGBT
-
Q2
TM
PWM3L
IGBT
Q4
42
IGBT
Q6
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
400 KW Dual Parallel Inverter Circuit
+ 750VDC
PWM1H
PWM2H
PWM3H
PWM4H
PWM5H
PWM6H
Va
Vb
Vc
PWM1L
PWM2L
PWM3L
PWM4L
PWM5L
PWM6L
-
TM
43
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Conclusion
All forms of energy are expensive, but as time progresses, renewable
energy generally gets cheaper. PV solar energy has made great strides in
the last five years as panels have become more efficient and costs of
production have decreased.
Optimized design and Maximum Power Point Tracking helps in harvesting
maximum energy at given condition.
We should aim at achieving Energy Independence by 2030.
Energy independence has got to be achieved through three
different sources namely renewable energy
(solar, wind and hydro power)
– Dr. A.P.J. Abdul Kalam
TM
44
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Q &A
Thank You
TM
45
Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore
and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a
Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc.
All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.