Adaptive Second-Order Sliding Mode Control of Buck Converters with Multi-Disturbances

Abstract

In this paper, a novel adaptive second-order sliding mode (2-SM) control approach, based on online zero-crossing detection, was proposed to solve the problems of the chattering and fixed control gain for buck converters with multi-disturbances. In modeling, the possible parameter perturbations and external disturbances of the converter system were contained. Instead of the traditional first-order sliding mode (1-SM), the twisting algorithm with 2-SM was adopted for the controller design, which could overcome the chattering problem and realize control continuity. Meanwhile, a novel adaptive mechanism was introduced to replace the conventional fixed control gain by time-varying control gain, the idea of which is to calculate the number of the zero-crossing points of the sliding surface online. As a result, the control magnitude of the improved controller could be reduced to a minimal admissible level, and the steady error of the output voltage could converge to the expected value. Furthermore, the robust stability of the converter system with multi-disturbances wads investigated. Comparative simulations and experiments validated the advantages of this paper as offering better robustness and control performance.

Simulation optimal and design of 3-kW DC-DC converter for pure electric vehicles

“…Many scientific papers have studied power converters, 1–22 which include different circuit topologies, soft switching control methods, and transformer optimization methods. However, the output powers of power converters in these scientific papers were not large, and there have been no in-depth studies on the input voltage range.…”

“…The experimental results indicated the feasibility of their method. Wang et al 18 proposed a control method to address the gain problem of the converter by introducing the adaptive mechanism into the control system. Both experimental and simulation results indicated that the power converter that used their proposed method had better robustness.…”