High efficiency solar Inverter solution

Wen Yongping
Solar inverter classification
Design Trend
Solar inverter classification & topologies
AC side:
Solar Inverters Classification
Central Inverter
Central inverter
~
Solar panels: Typical 30V / 200W per panel Series connected up to 600V DC (US), 1500V DC (EU)
Configurations for PV systems…
10.02.2010 Page 10
Power plant
Battery charging &
PV booster
PV panel
High power energy storage inverter
Feature:
Power up to MW but limited by battery
Cost is not sensitive
Can be modified from central inverter
High power EV charger module: 10 kW Three-phase Vienna PFC + ZVS FB
Devices Function Recommended IFX parts
D1…D6 Rectifier SiC G2 1200V
S1…S6 Boost switches 650V H5 / CoolMOS™ C6 600V
S7…S10 ZVSFB H3 1200V / SiC JFET 1200V
D7..D10 Rectification diodes Rapid2 650V / SiC G5 650V
Vienna Boost ZVS FB
Devices Function Recommended IFX parts
S1 Boost switch H5 650V / CoolMOS™ CP 600V
D1 Boost diode Rapid2 650V / SiC G3 600V/ G5 650V
S2/S3 LLC FETs H5 650V / CoolMOS™ C6/CFD2 600V
D2..D5 Rectification diodes Rapid2 650V / SiC G3 600V/ G5 650V
90...265Vac
Classification & configuration
Design Trend
Cumulative installed PV power [GWpeak]
P V
m o
d u
le c
Major drivers: Cell efficiency, Material useage, Economy of Scale
Source: E.R. Weber, „Aussichten der PV in Deutschland und Global, presented at 26th Symposium
Photovoltaic Solar Energy, Bad Staffelstein, Germany, March 2-4, 2011
The achievable efficiency range is largely dominated by the system architecture…
Source: B. Burger et al, „Extreme High efficiency PV Power Converters“, EPE 2009
Transformerless, 3-level
Transformerless, 2-level
LF Transformer
HF Transformer
2015: targeting > 99%!
…up to 98% conversion efficiency is state- of-the-art in transformerless PV inverters!
Source: G. Deboy, H. Ludwig, R. Mallwitz, R. Rupp, „New SiC JFET with Integrated Body Diode
Boosts Performance of Photovoltaic Systems”, Proc. PCIM, May 2011.
New design trend
2-level to 3-level
What s next? SiC JFET enabling a path towards 99% efficiency…
Agenda
9/2/2013 Page 22
low switching losses
Better power quality small
NPC1 NPC2
Short-circuit risk No risk possible
Turn off logistic Inner IGBT turn off
later than outer IGBT
NPC1
NPC2
Ic [A] 600V
U N
One complete phase leg in one module results in an optimised stray inductances. P≈9kVA… 80kVA
I C [A]
…_B22
Three phase PV inverter modules up to 9kw
Easy2B press-fit three phase bridge 3-level
Best silicon and Silicon carbide combination
3 Level Inverter with EconoPACK™ 4 Modules
The modules can be distributed over the whole
heat sink
3-Level Application EconoPACK™4
650V IGBT4-E4 softness comparison for IGBT turn-off - Vce @T=RT, Ic=300A
3
Output power up to approx. 25kW (PV Inverter)
Advantages:
Full reactive power capability (PV Inverter)
T1
T4
D1
D4
NPC2 topology
I C [A] EconoPACK4
Functionality of the boards.
Investigation aims:
How to minimize the current flowing between the modules over the ground line.
How to optimize the current sharing of parallel switching.
Parallel connection of three MA3L1200E07 with F3L020E07-F-P evaluation board
Picture of the measurement setup
Driver stage
Power supply for driver
Current distribution in the auxiliary emitter paths
a) With 0R as decoupling resistor a) With 4R7 as decoupling resistor
Current distribution in the auxiliary emitter paths
Current distribution on the AC terminals
Current distribution on the AC terminals of 3 parallel F3L400R07PT4 modules
a) Turn-on b) Turn-off
H5 IGBT and Rapid diode for string inverter
Continuous
S in
g le
I G
B T
TO-247 TO-220
D u
o P
a k
IKW50N65F5 / H5 50A
IKP40N65F5 / H5
www.infineon.com/trenchstop5
Set date Page 44 Copyright © Infineon Technologies 2011. All rights reserved.
Three Phase PV Modules up to 20kw each: Easy2B Booster Modules
Set date Page 45 Copyright © Infineon Technologies 2011. All rights reserved.
Three phase PV Modules up to 10kw each: Easy1B Booster Module
Single phase solution F4-50R07W2H3_B51, F4-75R07W2H3_B51
TIM Physics
TIM modules for solar
Spec:
TIM for F3L400R12PT4_B26
TIM is a concept to improve the thermal qualities of a module
The datasheet above show two changes:
With TIM, RthCH changes from typical to maximum
The value itself is reduced by 20% compared to standard modules
Take 125KW*110% for example: Ptot(IGBT)= 213W Tch=213w*Rthch*20%=2oC, in this case, Tj will reduce 2oC.
PrimePACK™ module for central inverter
Key Features
-Extended RBSOA
Tvjmax=175 C
2 pcs FF1400 parallel
Bad thermal performance
Alternative solution of PrimePACK™ ---- EconoDUAL™3
Key Features
225A-600A, 600V,1200V
Copper bonding 47% more current
High Efficiency
Easy to customize
Plug and play
All IGBT product families are used in solar