3kW PFC for Electrical Car Charger, Automotive Products Business Unit, Pavia, Italy

1. COMPANY CONFIDENTIAL 1
3kW PFC for Electrical Car Charger
Alex Lollio, Global Rotation Engineer
Automotive Products Business Unit
Pavia Design Centre, Italy
October, 2012 - April, 2013
Project Manager : Davide Giacomini
Program Mentor : Massimo Grasso

2. COMPANY CONFIDENTIAL
Outline
• Introduction
• Electrical Car Charger
• PFC Topologies
• IR Portfolio
• Overview of the IR115x PFC Controller
• 3kW Interleaved PFC Demoboard Realization Steps:
• FIRST STEP: Current Sense Transformers
• SECOND STEP: Clock Synchronization and Interleaving
• THIRD STEP: Current Sharing
• Measurement Results
• Board Image and Specifications
• Measurement Results (PF, Efficiency, Input Current after Load Step)
• IC Pinout Proposal
• Conclusion

3. COMPANY CONFIDENTIAL
Level 1: OnBoard Charger
Level 3:
Charger Station
1.5kW < Power < 3.5kW
16h < Charge Time < 7h
Level 2:
External Charger
3.5kW < Power < 10kW
7h < Charge Time < 2.5h
10kW < Power < 25kW
2.5h < Charge Time < 1h
Electrical Vehicle Charger Classification
http://avt.inl.gov/pdf/phev/phevInfrastructureReport08.pdf
Charge Time for 25kWh battery

4. COMPANY CONFIDENTIAL
Level 1 AC/DC Onboard Charger
Each Electrical Vehicle has an Onboard charger :
• High volume addressable market
• The target power is between 1.5kW and 3.5kW
• AC input : 16A@140V/240V → 2.2kW/3.8kW
(www.imsresearch.com)
• DC Output: 200 - 450V
AC SOURCE
AC/DC PFC DC/DC High Voltage
Battery
AC/DC PFC IS THE FOCUS OF THIS WORK
ONBOARD CHARGER
140V - 240V 200V - 450V
+
-

5. COMPANY CONFIDENTIAL
Power Factor Correction: Working Principle
The goal of the PFC is to obtain a phase alignment between the input voltage and
input current
AC INPUT
140V/240V
385V DC OUT
385V
0V
CONTROLLER
• PFC Figure of Merit → PF = P/(VRMS x IRMS) = Watts/V.A.
• The switch is the mayor contributor of switching loss (20kHz<FS<150kHz)
• The diode works in hard switching mode (reversed current when turning OFF)
Current
Voltage
LEGEND

6. COMPANY CONFIDENTIAL
Interleaved PFC: Working Principle
VIN
L1
COUT
VO
RLOAD
L2
IIN
S1
S2
I1
I2
ICOUT
IOUT
Benefit of interleaving:
• Input Ripple Current reduction
• Output Ripple Current reduction
• Better thermal management
• Core Magnetic size halved
ESINGLE = ½LIIN²
EINTERLEAVED = ½L(IIN/2)² + ½L(IIN/2)² = ¼LIIN²
S1
S2
ΔIL1
ΔIL2
IIN=IL1+IL2
I1
I2
ICOUT
IIN/2

7. COMPANY CONFIDENTIAL
Electrolytic Capacitor lifetime PFC
Dual Phase PFC
Single Phase PFC
EPCOS B43740
Lifetime of the output capacitor is doubled in the interleaved PFC

8. COMPANY CONFIDENTIAL
IR Portfolio
IR products for Interleaved PFC Application:
L1
COUT
VO
RLOAD
L2
IIN
S1
S2
I1
I2
ICOUT
IOUT
CONTROLLER
CONTROLLER
• IGBT
• Controller IR115x Family
Single Phase PFC
The Goal of this work is to adapt the IR115x Single
Phase PFC Controller to a Dual-Phase Interleaved
PFC Implementation

9. COMPANY CONFIDENTIAL
Outline
• Introduction
• Electrical Car Charger
• PFC Topologies
• IR Portfolio
• Overview of the IR115x PFC Controller
• 3kW Interleaved PFC Demoboard Realization Steps:
• FIRST STEP: Current Sense Transformers
• SECOND STEP: Clock Synchronization and Interleaving
• THIRD STEP: Current Sharing
• Measurement Results
• Board Image and Specifications
• Measurement Results (PF, Efficiency, Input Current after Load Step)
• IC Pinout Proposal
• Conclusion

10. COMPANY CONFIDENTIAL
3kW PFC Demoboard block diagram
L1
COUT
VO
RLOAD
L2
IIN
S1
S2
I1
I2
ICOUT
IOUT
IR1155
IR1155
CURRENT SHARINGCLOCK
INTERL.
• Current sensing is implemented using four current transformers (CT)
• Current sharing is implemented using a differential opamp
• Clock interleaving is implemented using two comparators LM393
Specs:
• VIN: 120V/240V
• Max IIN: 16A
• VOUT: 385V
• L: 250uH
• COUT: 3mF
• Freq: 50kHz
CT
CT

11. COMPANY CONFIDENTIAL
3kW PFC Demoboard Image
IGBT Diode
IGBT Diode
INDUCTORS
BRIDGE
RECT
1155
AC IN OUT
Specs:
• VIN: 120V/240V
• Max IIN: 16A
• VOUT: 385V
• L: 250uH
• COUT: 3mF
• Freq: 50kHz
• IGBT:
AUIRGP65
• DIODE:
ETX1506
33cm
27cm
INTERL.
CUR. SH.
CT
LOAD
VCC

12. COMPANY CONFIDENTIAL
Summary of the Project
• Oct : Study of PFC literature and IR products
• Nov : Microcap model realization of the IR1155
• Dec : Interleaving of two IRAC300 Demoboard + documentation
• Jan : 3kW Demoboard Schematic and Layout realization
• Feb : PCB assembly and measurements collecting
• March : Demoboard second release (Schematic + Layout)
• Apr :
• Documentation (application note, user guide, patent)
• Additional activities (Horn test software, LabView courses)