APPLICATION OF WAVELET-BASED SIGNAL DE-NOISING IN ESTIMATING FREQUENCY OF POWER SYSTEMS

摘要

Stability of power systems is closely dependent on the value of system frequency. Any mistake in accurate estimation of frequency could lead to system operation problems. In the present day power systems, presence of outside interference and noise coming from environment and instrument are unavoidable. As a result, input signal of the frequency measurement algorithms is covered by noises. Accuracy of frequency estimator algorithms is improved conspicuously if signal noise could be diminished. The problem is to recover the original signal from the noisy data while the recovered data is as close as possible to the original signal. In this paper a new scheme for estimating the frequency of power system based on wavelet signal de-noising is presented and analyzed. Performance of the proposed scheme is evaluated using different data. Various tests using simulated samples and real data recorded from a power system are performed and capabilities of the proposed algorithm are investigated.