Estimation of the reactive power of corrupted waveforms using the DWT

In recent times, due to the increased use of the reactive power, it is important to bill the electrical power consumption based on both the active and reactive power components. Reactive power is a very significant factor in electric power systems since it affects the efficiency of these systems. For this reason, the measurement of reactive energy is also important. Several methods are used to measure reactive power. Reactive energy meters provide accurate measurement only if the input is fundamental, because meters are constructed for operating under sinusoidal conditions. Due to the widespread use of nonlinear loads and natural disturbances such as lightning, the power quality of the waveforms is considerably deteriorated. As the corrupted waveforms are composed of nonstationary components also, in order to estimate the true reactive power of the power system fundamental component, a time-frequency analysis is required. Therefore, in this paper, a DWT based algorithm is proposed to effectively estimate the reactive power component of the power system.