有源电子式电流互感器高压侧电路设计的改进

IMPROVEMENTS ON CIRCUIT DESIGN FOR HIGH-VOLTAGE SIDE OF ACTIVE POWER ELECTRONIC CURRENT TRANSDUCER

提出了一种新的有源电子式电流互感器的高压侧电路设计方案。通过改进传统积分电路并适当选取元件参数改善了积分电路的低频幅值特性,并通过调整输入与输出信号之间的夹角,在抑制低频干扰的同时实现了相位补偿。高压侧电路的供电电源直接取自母线,在供电电路中设计了电压比较调节电路和备用电池自动投切电路,通过比较调节电路使输出电压与基准电压相比较产生调节信号,完成了对输出电压的调节;通过备用电池自动投切电路检测供电电路的电压输入,在电压输入低于给定值时将备用电池投入使用。软件系统中采用准同步算法以减少同步误差。实测表明,该设计方案抗干扰性能良好,准确性较高。

A new design scheme of circuit design for high voltage side of active electronic current transducer is proposed. By means of modifying traditional integrated circuit and appropriately choosing the parameters of elements, the low frequency amplitude characteristic of integrated circuit is improved. Through adjusting the included angle between the input and output signals, the phase compensation is realized while the low frequency interferences are restrained. The power source of high voltage side of the current transducer is directly acquired from the high voltage busbar and the voltage comparing/regulating circuit and automatic backup battery switching circuit are added into power supply circuit, the output voltage and the reference voltage are compared in the comparing/regulating circuit and the regulating signal is produced, then the regulation of output voltage is implemented. The input voltage from power source is detected by automatic battery switching circuit, when input voltage is lower than specified value, the backup battery will be put into use by automatic switching circuit. In corresponding software the quasi-synchronous algorithm is applied to reduce the synchronous error. Actual measuring results show that the improved design scheme possesses good anti-interference ability and higher measurement accuracy.