一、引言在交流调速系统中,电流检测装置不论是对系统实现闭环控制还是对系统实现保护功能来说,都是很重要的装置。以往,在交流调速系统中,一般采用在被测回路中串接低阻值电阻取样方法,或利用电流互感器进行电流的检测。在被测回路中串接低阻值电阻进行电流检测,虽然线路简单,但由于电阻要产生附加的压降和能耗,而且还造成被测回路与控制回路间电路上的联系,所以这种电流检测方法只适用于要求不高的小容量系统中;利用交流电流互感器进行电流检测,尽管在工频能达到一定 I. INTRODUCTION In the AC speed regulation system, the current detection device is a very important device, whether it is the closed-loop control of the system or the protection function of the system. In the past, in the AC speed regulation system, generally used in the loop under test low resistance sampling method, or the use of current transformer for current detection. Although the circuit is simple, there is additional voltage drop and energy consumption in the resistor, and it also causes the circuit between the circuit under test and the control loop to be connected. Therefore, this method Current detection method is only suitable for less demanding systems of small capacity; the use of AC current transformer current detection, although the frequency can reach a certain