Energy Storage Science and Technology ›› 2025, Vol. 14 ›› Issue (3): 1286-1298.doi: 10.19799/j.cnki.2095-4239.2024.1191

• Emerging Investigator Issue of Energy Storage • Previous Articles     Next Articles

A frequency-modulation power optimization method for energy storage power stations considering the transition state of charge-discharge and power constraints

Liqiang SUN1(), Shaojia DANG1,2, Gang LIU1, Shenyou WANG2, Pengfei HU2()   

  1. 1.Inner Mongolia Electric Power Research Institute, Huhehot 010020, Inner Mongolia, China
    2.Zhejiang University, Hangzhou 310000, Zhejiang, China
  • Received:2024-12-16 Revised:2025-02-15 Online:2025-03-28 Published:2025-04-28
  • Contact: Pengfei HU E-mail:sunliqiang_223@163.com;hpf@zju.edu.cn

Abstract:

Frequent charge-discharge cycles reduce the service life of energy storage power stations, and the transmission power of energy storage units connected to the power conversion system (PCS) may become too low, violating national energy management grid connection standards. To address this issue, this study proposes a frequency-modulation power optimization method for energy storage power stations that considers the transition state of charge-discharge and power constraints. This method divides the unit group into charging and discharging groups to meet their respective requirements. While ensuring that the alternating current (AC) power of the corresponding PCS does not fall below a set lower limit during energy storage unit output, each unit in the charging and discharging groups is dynamically updated based on the automatic generation control (AGC) instruction. This reduces the number of charge-discharge state transitions. Compared with traditional allocation strategies, the proposed strategy lowers frequency modulation costs and charge-discharge conversion frequency and ensures compliance with national grid connection standards by preventing the corresponding PCS AC side power from exceeding its limit during energy storage unit operation.

Key words: energy storage unit, AGC, frequency modulation cost, charge and discharge conversion, power constraint, distribution optimization

CLC Number: