In the IGBT overvoltage monitoring of the insulated gate bipolar transistor, the collector voltage is detected by the gate drive unit and compared with the reference value. If the collector voltage does not drop during the turn-on of the device, or the collector voltage on the previously turned-on device suddenly increases, it means that an overcurrent or short circuit has occurred.
The gate drive unit will block the pulse within a few microseconds; at the same time, keep the gate voltage during the IGBT on as small as possible (its maximum value is limited by the allowable value of the on-state loss) to reduce overcurrent. In the absence of an absorption circuit, the collector voltage molecular beam epitaxy is monitored on the gate drive unit. If it exceeds the set limit, increase the gate voltage slightly and reduce the di / dt of the current drop to limit the turn-off overvoltage. A fast diode is directly connected in parallel between the gate and emitter of the IGBT to prevent the very thin insulation between them from breakdown under transient overvoltage.
The programmable gate drive unit integrated in the IPM obtains the switching instructions from the control unit through the optical fiber interface and converts them to the required gate control voltage; at the same time, the IPM's switching state is fed back to the control unit and the converter Monitor. If a serious fault occurs, after sending the fault feedback signal, wait for a new command from the control unit.
Lc Fiber Coupler,Lc To Sc Coupler,Sc To Lc Coupler,Mpo To Lc Adapter
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