摘 要随着传统能源的日益枯竭，太阳能已经成为一种十分具有潜力的新能源，而光伏发电是太阳能最重要的利用方式。但目前光伏发电并没有普及，原因在于其效率低、成本高。而且由于光伏电池输出特性受光照强度及环境温度影响很大，具有明显的非线性特性。这样就产生了最大功率点跟踪(Maximum Power Point Tracking，简称MPPT)的问题。本文就是在此背景下，对如何提升光伏电池效率进行重点研究。其具体实现思路如下：根据光伏电池的输出特性，将Buck-Boost型DC/DC变换器实现的无损电阻应用到最大功率点控制系统中，并结合爬山法的控制方式，使光伏发电系统在不同光照强度和温度条件下有效地跟踪最大功率点。经MATLAB仿真验证，在不同光照强度及温度快速变化的条件下，基于无损电阻的最大功率点跟踪方法跟踪速度较快，而且追踪到最大功率后能稳定的工作在最大功率点附近。这样，不仅提高了效率，而且降低了传统方法中的不明干扰及错误判断。关键词：光伏电池；最大功率点跟踪(MPPT)；Buck-Boost；无损电阻AbstractWith the traditional energy depleting increasingly,PV power generation has bec-ome a new power which has great potential.But PV power generation is not univer-sal,it is because that the efficiency of PV power generation is very low and the c-ost of it is very high.Because of the photovoltaic cells are affected by light intensi-ty and temperature,and its output show the nonlinear.So it produces a problem of Maximum Power Point Tracking (MPPT).Researching focus of this paper is that how to improvethe efficiency of photo-voltaic cells.The concreting realization of thinking show below.According to the out-put characteristics ofphotovoltaic cells,using the DC/DC converter of Buck-Boost toachieve loss-free resistance type applied to the MPPT control system.And using Per-turb&Observe control system make PV power generation system effectively track t-he maximum power point under the conditions of different light intensity and temp-erature Perturb and Observe.By MATLAB simulation validated, the maximum powerpo-int tracking method of loss-free resistance tracks more quickly. And when trackingtomaximum power point,it can work nearthe maximumpower point steadily.So it not onlyimproves efficiency,but also reduces unknown interference or misjudgment of the tr-aditional method.Keywords: PV power generation; MPPT; Buck-Boost; Loss-free resistance