Safety Design Method for Control Board of New Energy Frequency Converter Based on IGBT Drive Protection

In response to the problems such as short-circuit de-saturation detection delay, drive under-voltage, over-temperature rating reduction, incorrect triggering and incomplete fault feedback existing in the control board of the new energy frequency converter under the conditions of high-voltage bus fluctuation and strong electromagnetic interference, a safety design method based on IGBT drive protection is proposed. This method constructs a collaborative link of short-circuit de-saturation, soft turn-off, under-voltage locking, over-temperature rating reduction, interlock protection and upper computer feedback, and incorporates PCB isolation wiring, Kelvin emitter circuit, sampling filtering and transient suppression into the board-level design. The test results show that the short-circuit de-saturation action time is 3.20 μs, the drive under-voltage locking time is 8.60 μs, the over-temperature protection action time is 12.40 ms, and the fault feedback accuracy rate is 100%.