Title: Power Factor Correction in an Electronic Ballast
1Power Factor Correction in an Electronic Ballast
- Using the SiC Schottky Diode
2Team
- Team Leader
- Clinton Livingston
- Team Members
- Travis Brignac
- Robin Kelley
- Advisor
- Dr. Mazzola
3Comparison Si pn vs. SiC Schottky
- Reverse biased pn junction diode does not turn
off fast enough during switching - This is due to the removal of excess carries from
the depletion region - Causes reverse recovery transient
- SiC Schottky diodes do not need to remove excess
carries from the depletion region - Eliminates reverse recovery transient.
- Allows for higher operating frequencies
4System / Hardware
120V AC
5EMI Filter / AC Rectifier
P-Spice Schematic
6EMI Filter Waveforms
Fully Rectified Sine Wave 169V pk.
7Power Factor Correction
Why?
Input Voltage/Current before PFC
- Conduction Cycles of Diodes in Rectifier
- Current spikes and is out of phase with the
voltage - Very poor power factor
8Power Factor Correction
Basic Schematic for PFC
9PFC Waveforms (Before Integration)
Input Voltage and Current
Average Current for PFC
Significant Noise Need
filtering to Reduce
10PFC Waveforms (Before Integration)
Boosted Output Voltage 120 Vrms in 282 Vdc out
11DC-AC Inverter
P-Spice Schematic
12Inverter Simulation Results
13Inverter Waveforms (Before Integration)
First Semester Test Results
Lamp Voltage f200kHz
Resistive Load f100kHz
14Inverter Waveforms (Before Integration)
Second Semester Test Results for Resistive Load
Output Voltage/Current
M1 Voltage/Current
M2 Voltage/Current
15Inverter Waveforms (Before Integration)
Second Semester Test Results for Lamp Load
Output Voltage/Current
M1 Voltage/Current
M2 Voltage/Current
16Integration Results
Packaging Market Ballast vs. First Hardware
Integration
17Integration Results
Test Result for Integrated PFC Circuitry
Input Voltage and Current Waveforms
18Integration Results
Test Result for Integrated DC-AC Inverter
M1 Voltage/Current After Integration
M2 Voltage/Current After Integration
19Integration Results
Test Result for Integrated DC-AC Inverter
(Continued)
Voltage and Current Waveforms before integration
Voltage and Current Waveforms after integration
20Constraints vs. Results
21Current / Future Work
- 4th Revision of PFC
- Additional Filtering
- 3rd Revision of Inverter
- Adjust for Reverse Recovery Problems
- Layout Revisions
- Smaller Package
- Final Testing
22Questions?
23