Time Delay Estimation and Compensation Method of Synchronous Signal Generator for PMU Test and Calibration
Zhekun Piao, Hao Liu · 2022 4th Asia Energy and Electrical Engineering Symposium (AEEES) · 2022
Synchronous phasor measurement unit (PMU) has been widely used in the field of power grid monitoring for its fast and real-time characteristics. The high-precision synchronous signal generator required for PMU test and calibration is an important part of the test system. However, the time delay error of the signal generator itself will seriously affect the accuracy of the output signal. Therefore, this paper analyses the problems of traditional correlation method in time delay estimation and proposes a time delay estimation method based on correlation method. On the basis of accurately calculating the time delay and combined with the characteristics of the hardware device, a time delay compensation method based on virtual second pulse is proposed to compensate the time delay error caused by the hardware factors of the signal generator. The simulation results show that the delay estimation accuracy of various test types can reach the nanosecond level. After being applied to the hardware device, the hardware delay error can be accurately compensated, and the compensated delay error can reach 1 µ s. Simulation and hardware experiments show that the proposed method can provide high-precision signal output for synchronous signal generator.