基于DSP的电磁式互感器误差测量研究

Research on DSP-Based Error Measurement for Electromagnetic Instrument Transformer

由于传统的互感器误差测量装置,其智能化程度比较低且测量精度不够高,故提出了一种基于DSP的电磁式互感器误差测量新技术。设计的互感器误差测量仪可在现场或实验室环境下,通过比较从标准互感器与待测互感器所采集的信号,完成对互感器误差的测量。设计的程控放大电路对原始信号进行幅值的调节,低通滤波器使输入AD转换器的信号为有效的基波信号,并兼顾其整体的抗干扰性能。采用DSP作为核心控制器,其反序间接寻址等特性能有效地对数据进行FFT运算,得出待测互感器的比差和相角误差。采用这种互感器误差测量仪可以提高效率,实现测量过程的自动化。

A new DSP-based error measurement for electromagnetic is proposed, aiming at the low lntelligent degree and measurement accuracy in traditional electromagnetic transformer calibrator. The error measurement for electromagnetic instrument transformer can be achieved by comparing the signals collected from the standard transformer （ST） and the detected transformer （DT） in the field or laboratory environment. The original signal amplitude will be regulated by the designed programmable amplifying circuit, and the low-pass filter will make the the signal passing AD converter be an effective fundamental harmonic signal. The anti-interference performance is also being concerned. DSP is taken used as the core Microcontroller. The FFT algorithm is applied to realize frequency spectrum computation. By comparing the data of DT with the data of ST, the ratio error and phase error are obtained. The results show that the measuring device can enhance the test efficiency and make the process automatic.