PMUs performance testing and evaluation in China

Phasor measurement units (PMU) are taking an increasingly important role in power system dynamic security monitoring and control. However, traditional Discrete Fourier Transforms (DFT) used by PMUs cannot obtain accurate phasor measurements during frequency excursion and transient events, being limited by its static phasor model. Therefore, the performance of PMUs under both static and dynamic conditions is fundamental. In this paper, the averaging effect of DFT is explored, which results in the measurement errors of PMUs under dynamic conditions. Then, a PMU testing system is introduced. With that, a centralized test aiming to improve the performance of M-class PMUs in China is accomplished by evaluating the PMUs from seven manufactures in China under static and dynamic conditions. The testing results show that the PMUs under test can satisfy most requirements in the standard by improving their algorithms. The testing data is analyzed to demonstrate the correctness of the theoretical derivation of the averaging effect of DFT.