output voltage ripple reduction for current-mode resonant
TRANSCRIPT
Output Voltage Ripple Reduction for Current-ModeResonant Converter
Shogo Katayama, Noriyuki Oiwa, Yasunori Kobori, Anna Kuwana, Haruo KobayashiGunma University [email protected]
1. Objective
3A-05
4. Proposed Circuit 5. Simulation 6. Conclusion
References
2. Background
1. EMI noise reduction Noise spectrum spread
LLC current-mode resonant converter
LLC resonant converter
2. Modulation ripple reduction Dual-phase configuration Reverse phase modulation
[1] M. Ochiai, Switching Power Supplies, Ohm Publishing (2015).
[2] D. Kawahara, S. Abe, S. Motomura, K. Domoto, Y. Ishizuka, T. Ninomiya, M. Shoyama, M. Kaga, “On the Parallel Operation of
LLC Current-Mode Resonant Converters in High-Voltage DC Power Distribution System” , IEICE Information and Communication Engineers,
Tech. Report (2013).
[3] K. Kawamura, T. Yamamoto, K. Hojo, “Circuit Technology of LLC Current Resonant Power Supply” , Fuji Electronic Journal, Vol.87 No.4 (2014)
EMI noise generation by current flowConventional noise reduction Analog filter Shield case
3. LLC Resonant Converter Noise spectrum spread for LLC converter
Switching frequency: 350kHzModulation signal: 500Hz Triangular
LC Resonant
Before ripple reduction
Parallel connection of power stages
Modulation ripple8mV
Steady-state ripple57mV
After ripple reductionReduce modulation ripple
Noise spectrum spreadby modulating the switchingfrequency
EMI noise reduction
Dual-phase configurationLLC resonant converterEach channel switchingfrequency modulation by reversephase
Modulation ripple reduction
Switching frequency: 350kHzModulate signal: 500Hz triangularWithout ripple reduction: 8mV rippleWith ripple reduction: 0mV rippleSwitching frequency pectrum: -13dBNoise spectrum spread equivalentto before ripple reduction
Simulate proposal circuit
Vref
C Load
VinVout
VCO
Driver
Q2
Q1
ErrorAmp
ΔVout
Ci
Ls1 Ls2
Lp
Vref
C Load
VinVout
Ci
VCO
Driver
Q2
Q1
ErrorAmp
ΔVout
Radiation noise
Conduction noise
Large scaleHigh cost
Proposed noise reduction Noise spectrum spread
Frequency
Am
plit
ud
e
Without spreading
Frequency
Am
plit
ud
e
With spreading
Feedback output voltage error to resonant frequency
05
101520253035404550
40 50 60 70 80
Ou
tpu
t V
olt
age
f1 = 52.1 kHz
Frequency area usage
Modulating switching frequency
Modulation ripple
GoalModulation ripple reduction
C Load
VinVout
Ci1
VCO
Driver
Q12
Q11
Vref
Ci2
VCO
Driver
Q22
Q21
ErrorAmp
ΔVout
PhaseRev
Reverse phase modulationeach power stage
Modulation ripple0mV
Steady-state ripple20mV to 56mV
Switching frequencyspectrum -13dB
Switching frequencyspectrum -11dB
Conditions