Selvam_Perumal
Junior Member level 2
Half bridge LLC resonant converter for below spec
Input voltage :300V to 350V
output voltage:50V @ 40A
Transformer details:
Llkg primary:0.81uH
Lprimary:7uH
Resonant capacitor:37.6nF
Resonant Frequency:912Khz
While loading the current to 10A at 300V input,the insufficient ZVS is observed by looking at SW node which is due to the fast slope of resonant current after turn off(50ns) which is not intended.
Due to this,the next switch is hard switched and increasing the losses in it which is higher than intended and failing over a time.
What would be the reason for current reversal during dead time(135ns).
FET Cds:287pF
Attached waveform:
Yellow:Resonant current
Blue:SW node
Red:Vcr node
Input voltage :300V to 350V
output voltage:50V @ 40A
Transformer details:
Llkg primary:0.81uH
Lprimary:7uH
Resonant capacitor:37.6nF
Resonant Frequency:912Khz
While loading the current to 10A at 300V input,the insufficient ZVS is observed by looking at SW node which is due to the fast slope of resonant current after turn off(50ns) which is not intended.
Due to this,the next switch is hard switched and increasing the losses in it which is higher than intended and failing over a time.
What would be the reason for current reversal during dead time(135ns).
FET Cds:287pF
Attached waveform:
Yellow:Resonant current
Blue:SW node
Red:Vcr node