无电压传感器的光伏MPPT研究

摘要

Maximum power point tracking(MPPT)plays an important role in PV array working. The power need be calcu-lated in available MPPT algorithms,therefore an improved control strategy without any voltage sensor is presented. The method, on the basis of the control of input current of DC-DC converter,realizes the self-optimization of duty cycle by means of step size varying,and makes the PV array output maximum power,by which the power needn′t be calculated in algorithm realization pro-cess. The method was tested and verified with simulation. The simulation results show that the method can realize the maximum power tracking accurately,and has perfect dynamic response characteristic and stability.%最大功率点跟踪在光伏阵列工作时发挥着重要作用,针对目前采用的最大功率点跟踪算法均需要计算功率,提出了一种无电压传感器的改进型控制策略.该方法基于DC-DC变换器输入电流的控制,通过变步长调节实现占空比自寻优,使光伏阵列输出最大功率,算法实现过程不需要功率计算.最后通过仿真对该方法进行验证和测试,结果表明,该方法能准确实现最大功率跟踪,同时动态响应特性和稳定性也较好.