固定电压法与改进电导增量法结合的光伏发电系统最大功率点跟踪

Maximum Power Point Tracking for Photovoltaic Generation System Combined Constant Voltage Method with Improved Conductance Increment Method

由于光照强度、光伏阵列温度、负载时时变化,使光伏电池阵列的最大功率点也发生变化,需采用适当的最大功率点跟踪(MPPT)算法提高光伏转换率。提出固定电压法与改进的电导增量法结合的MPPT方法,先采用固定电压法将光伏阵列的工作点调整到最大功率点附近,以保证跟踪的快速性;而后利用变步长的电导增量法,使工作点电压与最大功率点电压近似相等。仿真结果表明,固定电压与电导增量法结合追踪最大功率点能够快速、准确地跟踪光伏阵列的最大功率点,减少了在最大功率点振荡的能量损失,提高了光伏发电系统的能量转换率。

As the light intensity,photovoltaic array temperature and load change from time to time,the maximum power point tracking（ MPPT） of photovoltaic cell array is changed too,so it needs to adopt the appropriate MPPT algorithm to improve the photovoltaic conversion rate. The MPPT algorithm combined with constant voltage method and improved incremental conductance method is proposed. Firstly,constant voltage method is adopted to adjust the operating point of photovoltaic array near to maximum power point to ensure the fast MPPT. And then,improved incremental conductance method is adopted to make the voltage of operating point approximately be equal to the voltage of maximum power point. The simulation results show that the maximum power point of photovoltaic array can be tracked quickly and accurately combined with constant voltage method and improved incremental conductance method,which reduces the energy losses of maximum power point oscillation and improves the energy conversion rate of photovoltaic generation system.