Adaptive Control Strategy of Energy Storage System Participating in Primary Frequency Regulation

Chaoxiong Fang,Yuchen Tang,Rong Ye,Buying Wen,Zhenshan Zhu,Chengtao Ye,Zhangsui Lin

doi:10.3390/pr8060687

Abstract

In order to solve the capacity shortage problem in power system frequency regulation caused by large-scale integration of renewable energy, the battery energy storage-assisted frequency regulation is introduced. In this paper, an adaptive control strategy for primary frequency regulation of the energy storage system (ESS) was proposed. The control strategy combined virtual droop control, virtual inertial control, and virtual negative inertial control. The virtual inertial control was used to reduce the frequency change rate, and the virtual droop control was used to reduce the steady-state frequency deviation. The virtual droop control and the virtual inertia control were adopted in the frequency deterioration stage to slow down the frequency drop. While in the frequency recovery stage, the virtual negative inertia control worked together with the virtual droop control to accelerate the frequency recovery. Besides, the coefficients of the control methods were related to the state of charge (SOC) of ESS to avoid over-charging and over-discharging of the battery. Finally, a simulation model was built in MATLAB/SIMULINK, and case studies were conducted to verify the proposed control strategy. Results showed that the proposed method could meet the demand for frequency regulation and was beneficial to the cycle life of ESS.

Highlights

With the depletion of fossil fuels, large-scale renewable energy, such as wind energy and solar energy, is used for power generation
This paper presented an adaptive control strategy of energy storage system (ESS) participating in primary frequency regulation of the power system
The above simulation results of load disturbance (Load A), Load B, and Load C were similar to the results of Figure 17

Summary

Introduction

With the depletion of fossil fuels, large-scale renewable energy, such as wind energy and solar energy, is used for power generation. These kinds of renewable energy have volatility and uncertainty, and most of them lack inertia to power systems [1,2]. The frequency regulation capacity and response speed of the traditional power generator will not be able to meet the frequency regulation demand [4,5]. Since the charging and discharging power of ESS can be controlled rapidly and flexibly, using ESS to regulate power system frequency can improve the frequency regulation performance and reduce the reserve of traditional units To improve the frequency regulation capacity of the power system, the energy storage system (ESS), which has fast response characteristics, has attracted extensive attention in participating in power system auxiliary services [6].

Methods

Results

Conclusion