An effective control algorithm for dynamic voltage restorer under symmetrical and asymmetrical grid voltage conditions

Abstract

Introduction. Voltage sag, which is associated to a transitory drop in the root mean square voltage characterizing an electrical source network. During these perturbations, the corresponding electronic customers and devices will suffer from serious operating troubles causing dangerous damages. Purpose. In order to attenuate this disturbance effects, the Controlled Dynamic Voltage Restorer constitutes a very interesting solution among many others that have been proposed. The novelty of the proposed work consists in presenting an enhanced algorithm to control efficiently the dynamic voltage restorer when voltage sag is suddenly occurred. Methods. The proposed algorithm is based on an instantaneous phase locked loop using a multi variable filter to synthesize unitary signals involved in compensation voltages computation relative to the sag apparition. Practical value. A detailed study concerning typical voltage sag, which is consolidated by simulation and experimental results, is conducted to show the used algorithm’s effectiveness to cancel the corresponding voltage sag.

Dynamic Voltage Restorer as a Solution to Voltage Problems in Power Systems: Focus on Sags, Swells and Steady Fluctuations

“…For the generation of reference signals for a multifunctional operation of single-phase dynamic voltage restorers, Ahmed et al [69] proposed an enhanced single-phase quasi type-1 phase-locked loop (QT1-PLL) that offers superior harmonic robustness over conventional QT1-PLL. Boussaid et al [71] proposed an algorithm based on an instantaneous phaselocked loop (IPLL) using a multi-variable filter to synthesise unitary signals involved in compensation voltages required for compensation of voltage sags, thereby enhancing the control efficiency of the DVR in mitigating voltage sags. For voltage compensation using a DVR, Martins et al [73] proposed a method that relies on the construction of a voltage reference that considers the load power factor and utilises a recursive least square (RLS) technique to estimate the grid voltage magnitude and phase, delivering control action that is robust to harmonic distortions, sags and swells.…”

“…To demonstrate the performance of their proposed algorithm, which is based on IPLL using a multi-variable filter to synthesise unitary signals involved for compensation voltages required to mitigate voltage sags and enhance the efficiency of DVR control, Boussaid et al [71] ran software simulations and conducted experimental validations based on a set-up comprising hardware and a controller, implemented using the dSPACE 1104 platform.…”