Adaptive filter method for partial discharge on-line measurement system

On-line measurement of partial discharge (PD) is important to ensure safe operation for power transformer. The key of on-line measurement is to pick up discharge signal under strong interference. Aiming at how to prevent periodic interference, more papers have covered LMS adaptive filter, which needs to adjust many parameters and shows instability in pulse type interference. This paper discusses the fundamental principles and the design methods of LMS algorithm and robust RLS algorithm. The experiment results show that robust RLS algorithm can solve the problem existing in LMS algorithm and gain higher signal-to-noise ratio. Therefore, it can be applied in PD on-line measurement.