基于电导—扰动观察双模式的MPPT研究

Maximum Power Point Tracking Research Based on INC-P&O Dual Mode

随着光照强度和环境温度的变化,光伏电池的最大功率点(MPP)也随之改变。为了实现光伏系统最大功率点跟踪(MPPT),提出一种新的双模式控制最大功率点跟踪控制方法。在外界环境变化较小时,采用小步长扰动观察法(P&O),有效地减小稳态时功率振荡。当外界环境变化很大时采用电导增量法(INC),达到快速跟踪和避免跟踪失效。为了能在低占空比下获得高电压传输比,Z源升压变换器应用于光伏系统最大功率点跟踪电路。最后,通过仿真实验对比了P&O方法和双模式控制方法,结果验证了该方法的正确性和有效性。

With the change of light intensity and ambient temperature,the maximum power point(MPP)of photovoltaic systems is changed too.In order to achieve the maximum power point tracking(MPPT)of photovoltaic systems,a new double-model MPPT control method was proposed.The little size step perturbation and observation(P&O)method was used when the external environment changed little,the output power oscillation of the converter was effectively reduced.The incremental conductance(INC)method was adopted when the external environment occurred a substantial change so as to achieve fast tracking and avoid tracking failure.In order to provide high voltage conversion ratio with lower duty cycle,Z-source Boost converter was adopted to track the maximum power point of photovoltaic systems.Finally,compared the improvement of the P&O method and double-model method in the simulation and experiment,the correctness of theoretical analysis is validated.