To further improve the maximum power tracking performance of a photovoltaic power generation system, a sliding-mode control strategy is proposed based on a novel reaching law. A switchable linear sliding manifold applied to the maximum power tracking of the PV is proposed for the commonly used nonlinear sliding manifold which is prone to judgment error. This makes the system have faster response after disturbance. This paper adopts the Boost circuit as the controlled object, and by using the continuity and rapidity of the hyperbolic tangent function, designs a sliding-mode control strategy based on multiple power convergence laws with the speed of the exponential function and the smoothness of the power function, and verifies it on the Matlab/Simulink simulation platform. The results show that the sliding-mode control strategy with the new convergence law and switchable linear sliding-mold surface can achieve accurate tracking of the maximum power point when the light intensity, temperature, load and parameters change, and has quicker dynamic response and better anti-buffeting performance.

This work is supported by the National Natural Science Foundation of China (No. 51867007).