A K-ESPRIT Based Measurement Method with Wide Frequency Bandwidth

High ratio penetration of power electronic devices have added many inter-harmonics to the power system. These dynamically changing inter-harmonics raise new security issues, such as sub-synchronous oscillations (SSO) and frequency stability control, which propose new requirements to power system monitoring devices. In this paper, a fast synchronized measurement method with wide frequency bandwidth is proposed by using super-resolution characteristics of spatial spectrum estimation, and a kurtosis based method for estimating the number of signal frequency components is proposed, the stability under low SNR conditions of the method is improved, and the fast and high-precision measurement of the wide frequency bandwidth signal is realized. And then, a prototype of wide frequency bandwidth measurement is developed. The results of simulation test, laboratory device test and field data test verify the validity of the proposed method.