Detection of Power Quality Disturbances in Utility Grid with Wind Energy Penetration

This paper presents a method for detection of power quality (PQ) disturbances in power system network interfaced with wind energy power plant. Proposed algorithm uses multiresolution capability of discrete wavelet transform (DWT). PQ disturbances associated with operational events of wind energy generator such as outage and grid synchronization are analyzed. PQ issue associated with islanding event in the presence of wind energy has also been identified. The study is done with the help of an IEEE-13 node test system interfaced with wind generator in MATLAB / Simulink environment. Phase-A voltage signal caught on point of common coupling (PCC) was decomposed using DWT to receive detail coefficients up to fourth level of decomposition and approximation coefficient at fourth level of decomposition. The approximation coefficient at fourth level and detail coefficients at first and fourth level of decomposition are used to analyze the power quality issues associated with hybrid power system. The frequency and root mean square values of the voltage signal of phase-A are also analyzed for the recognition of the PQ problems.