Gao Changwei, Wang Wei, Huang Chongyang, Zheng Weiqiang
College of Electrical and Automation Engineering, Liaoning Institute of Science and Technology, Benxi, CO 117004, China.
School of Electrical Engineering, Shenyang University of Technology, Shenyang, CO 110870, China.
Sci Rep. 2023 Sep 12;13(1):15045. doi: 10.1038/s41598-023-42402-9.
Virtual synchronous generator (VSG) not only increases the inertia of grid-connected system, but also brings the problem of active power oscillation under grid disturbance. Therefore, VSG control strategy and system model order reduction method with transient electromagnetic power compensation are proposed. The closed-loop active power small signal model of the system is established, and the influence of transient electromagnetic power compensation on the power stability of VSG is analyzed based on root locus method. By removing the items which have little influence on the stability of the system in the small signal model, the order is reduced to obtain the equivalent second-order model of the system. According to the second-order model, the quantitative design criteria of the system parameters are given. The proposed transient electromagnetic power compensation strategy not only increases the transient equivalent damping of the system, but also does not affect the primary frequency modulation characteristics and will not cause large overshoot of the output active power. The experimental results are consistent with the theoretical analysis, which testify the effectiveness and correctness of the system control strategy and the model reduction method.
虚拟同步发电机（VSG）不仅增加了并网系统的惯性，还带来了电网扰动下的有功功率振荡问题。因此，提出了具有暂态电磁功率补偿的VSG控制策略和系统模型降阶方法。建立了系统的闭环有功功率小信号模型，并基于根轨迹法分析了暂态电磁功率补偿对VSG功率稳定性的影响。通过去除小信号模型中对系统稳定性影响较小的项进行降阶，得到系统的等效二阶模型。根据二阶模型给出了系统参数的定量设计准则。所提出的暂态电磁功率补偿策略不仅增加了系统的暂态等效阻尼，而且不影响一次调频特性，不会导致输出有功功率出现较大超调。实验结果与理论分析一致，验证了系统控制策略和模型降阶方法的有效性和正确性。
