A photovoltaic charging system with maximum power point tracking was designed according to the output characteristics of photovoltaic (PV) array and charging characteristics of battery. The system is controlled by the single chip of dsPIC30F5011 and adopts Cuk circuit as its main charging circuit, and uses four-state charging control strategy according to the terminal voltage of battery. In the under-charge stage,the battery is charged with trickle current based on PI regulator;in the fast-charge stage,the battery is charged with the maximum power point tracking (MPPT) based on incremental conductance method;in the over-charge and float-charge stage,the battery is charged with constant voltage which is compensated by temperature based on PI regulator. The experimental results indicate that this system can track the maximum power point quickly and work on that point stably when the ambient changes, and then the efficiency of PV array can be improved;the life span of battery can be prolonged with high-accuracy voltage control in over-charging and float-charging stages.%根据光伏阵列的输出特性与蓄电池充电特性,设计了一套具有最大功率点跟踪的光伏充电系统.该系统以dsPIC30F5011单片机为控制器,采用Cuk电路为充电主回路,根据蓄电池端电压对蓄电池采用四阶段充电控制策略.在欠电压充电阶段,采用基于PI调节的涓流对蓄电池充电；在快速充电的阶段,使用基于电导增量法的最大功率跟踪算法对蓄电池充电；在过冲与浮充阶段,使用基于PI调节的带有温度补偿的恒压充电.试验结果表明,最大功率点跟踪能快速跟踪外界环境的变化,并稳定工作在最大功率点,提高光伏电池的使用效率；过冲和浮充电压精度高,能延长蓄电池使用寿命.
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