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Start a SimulationPWM drives waveforms with severe oscillation problems
Dear support member, I have question about CAS300M12BM2 and CGD1200HB2P-BM2.
I used the CAS300M12BM2 module to build a dual active bridge converter circuit (as shown in Figure 1), with a power of 260W, where the transformer conversion ratio is 1:1, and the PWM drive waveform with a switching frequency of 50kHz and a dead time of 0.4us was generated by the TMS320F28335.
When I did the test experiment (without turning on the main power supply), I found that the PWM waveform of the driver board oscillated very seriously (as shown in Figure 2). At the same time, it can be noted that there is a noticeable difference between the drive waveform of the down tube and the top tube (as shown in Figure 3).
When I turn on the mains power supply for testing, there is also a significant difference in the primary and secondary voltages of the transformer, as shown in Figure 4, the primary voltage of the transformer will have a voltage drop for a period of time. I'm feeling very lost, how can I solve these problems?
Thank you very much!
Best regard.