Generalised single-phase p-q theory for active power filtering: simulation and DSP-based experimental investigation

Abstract

The single-phase p-q theory for the purpose of active power filtering in the case of single-phase loads is dealt with here. A simple modification is proposed to develop a generalised single-phase p-q theory that can be utilised under the condition of distorted utility voltage. A systematic study is presented by realising both direct and indirect current control techniques. The simulation as well as the digital signal processor (DSP) (DS1104 of dSPACE) based experimental results are discussed. The developed single-phase shunt active power filter (APF) prototype is tested under different operating conditions with different loads to evaluate the full capabilities of the proposed generalised theory for practical uses. The shunt APF reduces the source current total harmonics distortion (THD) from 27.2 to 3.4% under a distorted supply voltage with a THD of 16.2%.

An improved adaptive minimum dc-link voltage controller

“…As a result, it is necessary for the APF to perform dynamic reactive power compensation together with harmonic current compensation. The reference compensating current is calculated as follow [6,7]:…”

“…In order to solve this problem, the required minimum dc-link voltage is deducted and be used for APF [2]. However, the dynamic reactive power is neglected, in fact, it should not be ignored [3], especially in the case of load suddenly changing or start-up self-charging, this dc-link voltage controller will influence the compensation effect, and makes the APF lack of success to carry out fast dynamic harmonic current compensation under the minimum dc-link Voltage. So, an improved minimum dc-link voltage controller for APF is proposed.…”

Control Strategies for Multilevel APFs Based on the Windowed-FFT and Resonant Controllers

“…where λ represents the normalized frequency expressed in bin, according to IEC standard 61000-4-7 and 61000-4-30 for the measurement of harmonics and inter-harmonics [13].…”

“…The instantaneous reactive power theory (IRPT) or p-q theory is one of most popular algorithms for extracting the reference for active power filters [13]. The single-phase p-q theory is based on an instantaneous /2 lag of the voltage and current to define the original system as a pseudo two-phase system.…”

Single phase PQ theory based control of active power filter for power quality enhancement in DG connected microgrid

“…However, the main drawbacks like bulkiness, resonance, and fixation in the compensation further lead to the development of active power conditioning/filtering technology. The single-phase p-q theory for the purpose of active power filtering is proposed in [3] to mitigate current harmonics. Power conditioning with the help of active power filters can easily handle the major power quality issues.…”