Integrated Intelligent Energy ›› 2024, Vol. 46 ›› Issue (3): 35-44.doi: 10.3969/j.issn.2097-0706.2024.03.005

• Optimal Operation and Control • Previous Articles     Next Articles

Control strategy of virtual synchronous generators based on adaptive control parameter setting

DING Leyan(), KE Song(), YANG Jun(), SHI Xingye()   

  1. School of Electrical Engineering and Automation,Wuhan University,Wuhan 430072,China
  • Received:2023-05-11 Revised:2023-07-17 Online:2024-03-25 Published:2023-08-15
  • Contact: KE Song E-mail:dingleyan2001@whu.edu.cn;kesong1997@whu.edu.cn;jyang@whu.edu.cn;shixy1222@whu.edu.cn
  • Supported by:
    National Natural Science Foundation of China(51977154)

Abstract:

The new power system with new energy as the main body presents the characteristics of "low inertia and low damping". Since the virtual synchronous generator (VSG) control strategy can simulate the mechanical motion equation and electromagnetic characteristics of the synchronous generator, the strategy can enhance the stability of the power system by making the distributed inverters possess the inertia and damping characteristics of the synchronous generator. However, the strategy will compromise their dynamic regulation performances. Thus, a VSG control strategy based on adaptive control parameter setting is proposed. Firstly,the effects of inertia moment and damping coefficient on system frequency and output in transient process are analyzed by establishing a small signal model of VSGs. Then,the correlation between the adaptive moment of inertia, angular velocity variation ratio and angular velocity offset,and the correlation between the adaptive damping coefficient and the angular velocity offset are analyzed by the power angle-frequency oscillation curve of a synchronous generator. The selection principle for the inertia moment and damping coefficient in different intervals is obtained,and their calculation formula and the trigger thresholds are designed. Furthermore,by adding adaptive droop coefficient considering the upper and lower limits of frequency modulation power,a control strategy of VSGs based on adaptive control parameter setting is proposed. Finally, the simulation analysis on the off-grid VSG model is built by Matlab/Simulink,and the simulation results verify that the proposed control strategy can reduce the frequency offset, and improve the frequency stability and dynamic regulation ability of the system.

Key words: new power system, virtual synchronous generator, moment of inertia, damping coefficient, adaptive control, droop coefficient

CLC Number: