A Control Strategy for Battery Energy Storage Systems Participating in Primary Frequency Control Considering the Disturbance Type

Ya Meng,Xiaolong Liu,Xinran Li,Shujuan Li,Piao Xu,Xiwen Cui

doi:10.1109/access.2021.3094309

Abstract

In power systems, various types of disturbances can randomly affect the active power balance, which can result in unexpected frequency changes. A battery energy storage system (BESS) is an effective technique to assist power system primary frequency control. In this work, a comprehensive self-adaptive strategy considering load disturbance types is proposed that enables BESS participation in the primary frequency control of power grids. First, the different types of load disturbances in the power system are divided into two categories, namely, step disturbance and continuous small disturbance. Then, the advantages of virtual inertia control and virtual droop control are taken into full consideration. Model A and Model B are proposed to match the two load disturbance types. Model A is used to rapidly prevent sudden changes in frequency under step disturbance conditions without restricting the state of charge (SOC) of the BESS. Under the conditions of continuous small disturbances, we further propose Model B in which primary frequency control is realized while considering SOC recovery. Compared with the previous primary frequency control methods, the presented approach significantly improves the stability of complicated and changeable power systems. Meanwhile, it fulfills the frequency control requirements with superior frequency control performance.

Highlights

With the rapid development of the economy, urban power grids in economically developed regions are characterized by large capacity, multiple load types, and high load density
When the battery energy storage system (BESS) is used in auxiliary power grid frequency control, it significantly improves the power grid frequency control performance and effectively reduces the frequency control standby of traditional units [8], [9]
On the one hand, we focus on a comprehensive control strategy to meet the different frequency control requirements caused by different load disturbances

Summary

INTRODUCTION

With the rapid development of the economy, urban power grids in economically developed regions are characterized by large capacity, multiple load types, and high load density. Y. Meng et al.: Control Strategy for BESSs Participating in Primary Frequency Control will improve the BESS frequency control performance and effectively reduce the capacity configuration of the energy storage power supply [10]. Research on BESSs participating in primary frequency control has mainly focused on enhancing the frequency stability of power systems and improving the operating economy of BESSs. Some studies use BESS to simulate the working principle of traditional generator sets with the goal of improving the frequency control effects [12], [27]. This method takes into account the capacity limitation of battery energy storage and treats it differently from conventional frequency modulation power supplies It can improve the SOC operating state while meeting the performance of primary frequency modulation. Frequency control, which can be used by different types of BESSs

BASIC CONTROL METHOD OF ENERGY STORAGE FREQUENCY CONTROL

VIRTUAL DROOP CONTROL

COMBINATION CONTROL STRATEGY

Findings

COMPARATIVE METHODS IN REFERENCES