虚拟同步机惯量及阻尼系数协调优化方法

为了提升虚拟同步机(virtual synchronous generator,?VSG)在各种扰动下的动态响应，提出了一种虚拟惯量及阻尼系数的参数协调优化方法。推导了VSG有功指令与输出电磁功率之间的二阶传递函数，定量分析了VSG动态响应特性与虚拟惯量及阻尼系数的关系。在扰动的初期调整两参数使VSG呈欠阻尼状态实现加快调节，在扰动后期则使VSG呈过阻尼状态来减小超调，兼顾功率调节速度和频率稳定性，降低储能充放电深度。最后，基于Matlab-Simulink仿真软件开展了VSG出力扰动和电网故障扰动下的仿真，对比参数优化前后的动态响应。结果验证了所提优化方法的优越性及稳定性，可以有效提升VSG的动态响应能力，延长VSG储能寿命。

Coordination and optimization strategy of virtual inertia and damping coefficient of a virtual synchronous generator

To improve the dynamic response of a virtual synchronous generator (VSG) under various disturbances, a parameter coordination optimization method of virtual inertia and damping coefficient is proposed. The second-order transfer function between the VSG active power command and output electromagnetic power is deduced, and the relationship between the VSG dynamic response characteristics and virtual inertia and damping coefficient is quantitatively analyzed. The two parameters are adjusted in early disturbance to make the underdamped VSG speed up regulation, and make the VSG overdamped during late disturbance to reduce overshoot. This method takes into account both power regulation speed and frequency stability, and reduces the charge and discharge depth of energy storage. Finally, simulation under VSG output disturbance and power grid fault disturbance is carried out based on Matlab-Simulink simulation software. The dynamic responses before and after parameter optimization are compared. The results verify the superiority and stability of the proposed optimization method. This can effectively improve the dynamic response of the VSG and prolong the energy storage life of VSG. This work is supported by the National Natural Science Foundation of China (No. 51377119).