Hiper LLC Transformer
I am using a Santronics LLC transformer to Create a 190 V bus for a PWM AC bridge output.
That design is working properly.
I am trying to approve an alternate vendor to produce the LLC transformer.
Their design outputs proper voltage at max current( 2 A @ 115 VAC 60 HZ.
However Q10 and Q11 (RD189)get abnormally hot and it looks from the LLC waveform attached that zero crossing switching is not happening.
Can you provide any advice?
Also can you submit more than one attachment at a time?
Comments
1) Primary # of turns 26 turns #19 litz
2) Secondary # of turns 46 ct #21 Litz
3) Primary open circuit inductance 266-294uH
4) Primary leakage inductance. 63-77uH
Also when I try to attach more than one picture the next one replaces the one I sent first.
#2 answer doesn't make sense.
What is your PFC output voltage, and LLC output voltage and current?
What is your PFC output voltage, and LLC output voltage and current?
385 VDC, 190 VDC, Green trace in atttachment.
The waveform you attached is a 60Hz waveform, not the LLC stage waveforms. Your problem is that the LLC MOSETs are hot, after you tried a different LLC transformer, correct? I need to see the LLC waveforms.
Pls. show me a comparison of the original, and the new transformers. What specs are different? Primary inductance? Leakage? etc.
The LLC waveforms are in the first post.
I need to see the half-bridge output voltage waveform.
That is, the voltage at the meeting point of the 2 main MOSFETs.
Attached
The yellow waveforms look like the voltage across the transformer primary voltage, not the voltage on the half-bridge output.
I need to see if the MOSFETs are operating in ZVS. So pls. zoom in on 1 cycle so I can see the half-bridge rise and fall times.
Can you tell me:
1) Primary # of turns
2) Secondary # of turns
3) Primary open circuit inducance
4) Primary leakage inductance (with secondaries shorted)
Yes you can place more than 1 attachment at a time.