三相并网逆变器直接功率控制和直接功率预测控制的对比

根据三相并网逆变器的动态数学模型,详细推导和分析并网逆变器各电压矢量对有功功率变化和无功功率变化的影响。根据有功功率变化与无功功率变化的曲线去选择最佳的电压矢量,使三相并网逆变器输出的有功功率和无功功率脉动较小。在此基础上,提了一种基于新开关表的直接功率控制。同时,采用一种新的直接功率预测控制,该控制策略与空间矢量脉宽调制相结合,实现有功功率和无功功率的解耦控制与功率因数任意可调。最后对直接功率控制和直接功率预测控制进行对比实验。实验表明了方案的可行性和正确性。

Comparative Study for Direct Power Control and Direct Power Predictive Control in Three-Phase Grid-Connected Inverters

According to the dynamic mathematical model of three-phase grid-connected inverters,the influence on the active power change and the reactive power change is derived and analyzed in detail for grid-connected inverters when the voltage vectors are impressed.The best voltage vector is selected according to the signs of the active power change and the reactive power change,which can make the ripple of the active power and the reactive power small.On this basis,a direct power control(DPC)based on a new switching table is proposed.A novel direct power predictive control is adopted at same time,which is combined with space vector pulse modulation(SVPWM).This control strategy achieves the decoupling control for the active power and reactive power and an adjustable power factor.At last,comparative experiments are tested for direct power control and direct power predictive control(DPPC).The feasibility and correctness of the control strategy are verified by experimental results.