Hello, I have designed a flyback converter using the UCC28740 chip. During power-on testing, the duty cycle of the Vgs waveform of the MOSFET in the flyback converter is very small both under no-load and full-load conditions, and the duty cycle under full-load is slightly larger than that under no-load. Additionally, the output voltage drops significantly under full-load: the rated output voltage is 24V, but it only reaches 12V under full-load operating conditions. Why is this the case? Could you please tell me what the possible reasons are? I look forward to your reply.
