具有阻尼和惯性的电流下垂控制研究

针对虚拟同步发电机控制策略的优良特性,研究了其在电流下垂控制中的应用。采用电流下垂控制算法取代虚拟同步发电机的有功/频率调节和无功/电压调节控制策略,保留其机械转动所具有的惯性和阻尼特性,舍弃其定子电气模块,使逆变器不仅具有电流下垂控制的优越性能,而且具备虚拟同步发电机的阻尼和惯性特征,增强电网频率和电压幅值的稳定性。通过在电压/电流双闭环控制器中引入虚拟阻抗,提升并网逆变器的鲁棒性。仿真实验结果验证了所提出控制策略的可行性和有效性。

Study on current droop control with damping and inertia

The application of virtual synchronous generator algorithm in current droop control is studied for the excellent characteristics of control strategy of virtual synchronous generator. Current droop control method is used to replace the control strategy of the active power/frequency adjustment and reactive power/voltage regulation based on the mathematical model of virtual synchronous generator, reserving the inertia and damping characteristics of the mechanical rotation of the synchronous generator and discarding its stator electrical model, so that the inverter not only has the superior performance of the current droop control, but also owns damping and inertial characteristics of the synchronous generator, and increasing the stability of grid frequency and voltage amplitude. The grid-connected inverter''s robustness is enhanced by introducing virtual impedance in voltage/current closed-loop controller. Simulation results verify the feasibility and effectiveness of the proposed control strategy. This work is supported by National Natural Science Foundation of China (No. 11472058).