Real-time measurement of power quantities in fully distorted systems

This paper proposes a time-domain technique in order to meter the power quantities of three-phase systems that are contained in IEEE Standard 1459-2000. The proposed method does not need the spectral analysis which is the base of time-frequency methods. It is based on a recursive implementation of the Park and Clark transformations that are employed to obtain the fundamental components of voltage and currents waveforms to calculate the powers of three-phase systems in every distributed network whether sinusoidal, non-sinusoidal, balanced or unbalanced. The recursive algorithm avoids the low-pass filtering stage that in turn results in uncertainty and delay in calculating the fundamental components of the waveforms in synchronous rotating frame. To investigate the effectiveness of the proposed method, it is compared to the Direct Park-based methods in calculating the quantities. In implementation of this technique, the effects of voltage and current transducers are considered as well. According to the simulation and implementation results, the real-time method can calculate the power quantities with less delay and more accuracy.