Expansion of Current Physical Components (CPC) to Three-Phase Four-Wire Systems under Non-Ideal Waveforms by the AUPQS

Abstract

Active power compensators have been extensively using the time domain compensation theories. However, they are not able to separately recognize and compensate power properties regarding the load–terminal characteristics (i.e.unbalance, distorted and so on). The CPC theory in the frequency domain, on the contrary, can accurately recognize the load–terminal components in three–phase three–wire systems. Nevertheless, the CPC–based compensation algorithm is not easy to implement in terms of hardware requirements even in three–wire systems because of intensive Fourier decompositions. This paper intends to analyze the applicability and performance of a switch–mode compensator controlled by advanced generalized theory of instantaneous power (A–GTIP) based on the CPC theory. The focus will be the oscillating instantaneous powers that lead to torque oscillations in a weak micro–grid. First, the CPC theory are redefined in the time–domain based on the A–GTIP definitions. Then, it is shown that an advanced universal power quality conditioning system (AUPQS) can effectively recognize and accurately compensate the physical components of the source–end currents in three–phase four–wire systems. Effectiveness of the proposed AUPQS is confirmed by Matlab/Simulink simulations.