新型MPPT算法在光伏并网系统中的应用

New MPPT method in the application of photovoltaic grid-connected system

光伏并网系统在天气急剧变化时,采用传统的最大功率跟踪算法会产生较大误判,不仅造成电池板功率的损失,而且还会导致并网电流的畸变。针对这一问题,对传统扰动观察法进行了改进,提出了一种新型MPPT算法,有效地防止了功率误判。将此新型算法配合电压电流双环控制应用于光伏并网系统。从仿真结果看到,在光照突变和电网电压扰动时,并网电流均能够快速跟踪电网电压的相位和频率。表明了新型算法的正确性和有效性。

In case of the weather abrupt changing rapidly, it is unable to determine the right tracking direction using the tra- ditional maximum power point trucking method in PV systems. The new MPPT method was proposed based on the traditional P＆O method in order to improve the system performance. The power of miscarriage justice was prevented by the new method. And the new method with the voltage and current double loop control is applied to the photovoltaic grid-connected system. In the light of mutation and grid vo]tage disturbance situation, power grid voltage of phase and frequency are all tracked quickly by the grid cur- rent and the power factor was achieved one. Through the analysis of the simulation results, show that the new algorithm is correct and effective.