应用于直流电源逆变的虚拟同步机控制算法研究

Research on Control Algorithm for Virtual Synchronous Machines Applied to DC Power Inverters

直流电源逆变器具有低惯量、欠阻尼的缺点,惯性和阻尼的缺失会导致系统频率变化率过快、变化量过大的问题。针对上述问题,提出一种应用于直流电源逆变的虚拟同步机(VSG)控制算法。在逆变器控制中加入了有功频率和无功电压控制环节,逆变器具有同步发电机的调频调压特性以及惯性和阻尼特性。最后,在MATLAB/Simulink中搭建了一台10 kW的VSG系统。仿真结果表明,所提算法能减小负荷突变造成系统功率和频率的冲击和振荡,提高了系统的稳定性。

The DC power inverter has such disadvantages as low inertia and under-damping,and lack of inertia and damping might lead to a higher frequency fluctuation rate and larger amount of fluctuation.Aiming at above mentioned problems,a virtual synchronous machine(VSG)control algorithm applicable to the DC power supply inverter was presented.Active frequency control and reactive voltage control were added to inverter control so that the inverter might acquire frequency and voltage regulation characteristics as well as inertial and damping characters of the synchronous generator.Finally,a 10 kW VSG system was built in Matlab/Simulink.Simulation results showed that the proposed algorithm could reduce the impact and oscillation of system power and frequency caused by sudden load changes,thus improving the stability of the system.