光伏阵列的功率输出极易受到光照强度、温度变化等环境因素的影响。为了保证光伏发电系统保持高效的输出，最大功率点跟踪技术就显得尤为重要。针对目前的最大功率点跟踪技术仍存在功率振荡、步长选择以及跟踪时间等问题，提出一种基于功率对电压的导数变化的变步长最大功率点跟踪算法。通过实时数字仿真器建立半实物125 kW“T”型三电平三相光伏发电系统，对比分析了改进型算法和传统两段步长算法的静态特性和动态特性，实验结果表明：所提出算法具有更好的有效性和实用性。

The power output of photovoltaic array is affected by the environmental factors such as light intensity and temperature change. In order to ensure that the photovoltaic power generation system to maintain efficient output, the maximum power point tracking technology is particularly important. In allusion to the current maximum power point tracking technology still existing power oscillation, step selection and tracking time issues, a maximum power point tracking algorithm based on the change in the derivative of power on voltage is proposed. Through the Real Time Digital Simulator to build a semi-physical 125kW T-type three-level three-phase photovoltaic generation system, the dynamic and static characteristics of the improved algorithm and the traditional two step algorithm are compared and analyzed. Experimental results show that the proposed algorithm is more effective and practical.

TM615

四川省科技支撑计划项目（2015GZ0136）资助