The Detection Of Short-Term Power Quality And Measurement Of Interharmonics Parameters

Electric power shows powerful strength as a kind of important energy sources from its birth. In contemporary society, electric power even becomes an indispensable energy sources. However, with the widely use of various kinds of power electronics devices and nonlinear loads in power network, the problem of power quality becomes one of the problems which is paid attention for by customers and power supply department. High quality electric power has a fatal significance for guaranteeing electric devices' safely and economically operation, improving products' quality and guaranteeing normal life of the residents.To improve power quality, we have to diagnose, localize and classify the power quality problem. However, how to detect and localize waveform distortion and the start and end of disturbance or fault becomes the prime problem of the detection of power quality and the analysis of fault. In this paper, a new method based on the idea of EMD (Empirical Mode Decomposition) for the fast localization of power quality disturbances — Triangle Mode Method is presented. This method reserves the disturbance information of signals through superposing a triangle mode on the original signal to localize disturbance. And aiming at the characteristics of the triangle mode, an improved and simplified method of it is also presented, which makes the proposed method localize disturbance more simply, exactly and rapidly. Simulation results prove the effectiveness of the proposed method.Short-term voltage disturbances in power system are known as the most serious...