Research and Design of PV MPPT Based on STM32

Abstract

Aiming at the problem of maximum power point tracking (MPPT) of PV power generation, combined with the purpose of temperature adjustment of rural PV heating system, the MPPT method based on the model of adjustable load resistance matching is proposed. The output characteristics of PV cells and the principle of load matching are analyzed, and the MPPT of PV generation is realized by perturbation and observation (P&O) method. Regarding the heating equipment as the resistive load, a group of resistors with a wide range and small step length which can be controlled by the relay are designed to test. Finally, taking STM32 as the core processor, adjusting the step size and tracking the change of PV output voltage, the controller can track the change of the external environment accurately, that is, it can track the maximum power point of a PV power system effectively.