扰动观察法的MPPT负载突变误判现象研究

在光伏系统中,Boost电路常常作为前级电路,使其工作在最大功率点处,以向后级电路传输最大的能量。然而在系统运行过程中,由于后级电路在调整过程中以及到达稳态后负载的加载、掉载等原因,会造成后级电路等效输入电阻(前级电路输出电阻)发生变化。因此可能会造成前级Boost电路功率点比较发生错误,从而发生误判现象。针对前级电路在应用扰动观察法做MPPT时,负载突变对电路误判的影响,对电路从开始调整到电路稳态后的全过程中的误判现象做了理论分析和总结。最后搭建了Boost实验电路验证了分析的正确性。

On Misjudgment Phenomenon of MPPT Load Mutation Based on Perturbation and Observation Method

In the photovoltaic system,Boost circuit acts as a preceding circuit to transmit maximum energy to backward circuit,achieving maximum power point.However,in the system operation,loading and off load in backward circuit adjustment may cause changes in equivalent input resistance.As a result,there will be something wrong with preceding Boost circuit power point,which may lead to misjudgment phenomenon.The paper focuses on effect of load mutation on circuit misjudgment when perturbation and observation method is applied to make MPPT.Misjudgment of the whole circuit process from adjusting to circuit steady state is analyzed and summarized.Finally,Boost circuit is established to verify its correctness。