单相光伏并网逆变器控制策略的仿真

本文针对小型光伏并网装置,提出了一种新的控制策略.对单相太阳能光伏并网系统的工作原理进行了分析,建立了光伏并网系统的数学模型,由于锁相环技术可以使逆变器输出的电流与电网电压基本同频同相,电网电压前馈可以抵消电网对光伏并网系统的影响,从而提出了基于锁相环技术和电压前馈控制相结合的复合控制策略.在Matlab/Simulink环境下建立了系统仿真模型,并分别采取了不同的控制策略进行仿真.结果表明,文中提出的控制策略可以使光伏并网系统输出更好的并网电流波形,降低总谐波畸变率.

Simulation on single phase photovoltaic grid-connected inverter and its control strategy

A kind of new control strategy, which contraposed small photovoltaic grid-connected system, is proposed. The operating principle of the system of signal-phase grid-connected photovoltaic power is analyzed, and the mathematical model of photovoltaic grid-connected system is established. Because of PLL technique could make the inverter output current and utility-grid voltage with the same frequency and phase, and the influence of grid on photovohaic grid-connected system could be counteracted with the feed-forward control of utility-grid voltage, the compound control strategy, which based on the eombina- tionofphase-lockedloop （PLL） technique and feed-forward control of voltage , is put forward. The power output stage model of system is established under Matlab/Simulink, and different control strategies are compared. The results prove that the waveform of grid-connected current output from photovoltaic grid-connected system can be improved by the control strategy proposed in this paper and the THD is reduced.