The power cells can be damaged when short-circuit occurred in the three-phase four-wire 400 Hz solid-state power supply. The traditional methods can not ensure the rapid removal of short-circuit fault. In allusion to their limitation, a method of short-circuit protection based on software-hardware coordination control is presented. The method determines the conditions by using the current limit and the rate of transient short-circuit change. The method can overcome the instantaneous weak overload of power electronic devices and ensure the rapid removal of short-circuit fault and the continuous power supply by the quick turnoff of solid-state switch at the zero crossing and the constant-current source. The experiment results show that the method is useful and effective.%针对三相四线制静止式中频电源负载短路时功率器件极易损坏,传统的短路保护方法不能抑制短路瞬间快速上升的短路电流,且会造成负载供电断续等问题,在对传统短路限流保护加以改进的基础上,提出了一种软硬件协同控制的短路限流保护方法.为了抑制短路电流的快速上升,该方法运用固态断路器过零点瞬时关断的能力,采用短路限流值及短路电流瞬态变化率双重判断条件.结合短路时切换为恒流源控制的手段,克服了电力电子设备瞬时过载能力弱的缺点.实验结果证明了该方法可以保证短路故障的迅速切除及负载的持续供电.
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