Wavelet-based online disturbance monitoring for local power system

Abstract

Industries with sensitive electrical loads are becoming more and more dependent on the quality of local power system.The quality of a power supply is largely synonymous with the voltage quality for the power system. The general strategy to assure voltage quality and sound operation of a sensitive load is to monitor the supply voltage and take appropriate countermeasures based on detection of voltage disturbance that exceed the load tolerance limits. So rapid monitoring and identifying the voltage disturbance are desired features for power quality enhancement. This paper introduces a new on-line power quality disturbance monitoring approach based on wavelet transform. This approach can identify voltage disturbances and discriminates the type of event that has result in the voltage disturbance. The proposed approach is significantly and more precise in discriminating the type of transient event than conventional voltage-based disturbance detection approaches. Feasibility of the proposed approach is demonstrated based on the monitoring of an actual local power system in Sichuan province of China.