Robust control of frequency and voltage of power grid in remote areas with WT-PV-BESS penetration—A Markov jump system approach

Abstract

Power grids located in remote areas are weakly connected with the main power system and are confronted with unpredictable disasters like bushfires, thunder strikes and mudslides. These contingencies will cause major changes in the networked system topology and stability issues. Traditional control methods fail to address these stochastic structural disruptions, leading to voltage/frequency violations and inadequate resilience. To overcome this, this paper aims to propose a novel robust control strategy for frequency and voltage restoration of the remote area power grid (RAPG) subjected to the happening of major contingencies, via a new routine called the Markov Jump System (MJS) approach, enabling adaptive control under random structural disruptions. Firstly, a synergetic operation strategy for the photovoltaic (PV), wind turbine (WT) and battery energy storage system (BESS) to engage in grid frequency and bus voltage support is proposed. Afterwards, the networked MJS model of the distributed WT-PV-BESS is developed, where the topology-changing contingencies are modelled as a kind of jumping behavior of the MJS from one mode to another. Subsequently, an output feedback control is proposed for the stabilization of the MJS model in voltage and frequency regulation mission. Simulations under diverse scenarios show that the proposed method is able to reduce voltage deviation compared to traditional consensus control and ensure frequency stability, as well as BESS state-of-charge (SoC) balance, compared to conventional coherence control. The results validate the superiority of the MJS method to enhance grid resilience under random faults.