单电感双输出(SIDO) Buck变换器在受到负载扰动时,支路间存在严重交叉耦合影响,输出信号易受到高频测量噪声等不确定因素影响.针对上述问题,提出一种基于高阶滤波超螺旋扩张状态观测器(ESO)的滑模自抗扰控制策略.首先,根据SIDO Buck变换器的数学模型,将内部参数影响和外部扰动等不确定因素分离为集总扰动,建立不考虑物理参数的自抗扰模型;其次,设计一种高阶滤波超螺旋扩张状态观测器,更精准地估计补偿集总扰动,提高抑制噪声和交叉影响的能力,并根据有限时间稳定性理论证明其稳定性;再次,设计改进的超螺旋滑模反馈控制律,保证滑动模态阶段和到达阶段能快速收敛,同时更好地抑制抖振,并选取李雅普诺夫函数对反馈控制律进行稳定性分析;最后,利用仿真和实验对比验证了所提控制策略能有效减小交叉影响、抑制噪声、提高系统的暂态性能.

When a single-inductor dual-output (SIDO) Buck converter is disturbed by the load, a serious cross-coupling effect arises between branches, and the output signals are vulnerable to uncertain factors such as high-frequency measurement noise. To address the above issues, an improved sliding mode disturbance-observer-based control strategy based on a high-order filtering super-twisting extended state observer (HOFST-ESO) is proposed. First, the internal parameter influences and external disturbances are decoupled as lumped disturbances based on the mathematical model of the SIDO Buck converter to establish a disturbance-observer-based model without considering physical parameters. Next, a high-order filtering super-twisting extended state observer is designed to more accurately estimate and compensate for the lumped disturbances, enhancing the ability to suppress noise and cross-coupling effects. The stability of the observer is proven based on the finite-time stability theory. Then, an improved super-twisting sliding mode feedback control law is designed to ensure rapid convergence in both the sliding mode phase and the reaching phase, while better suppressing chattering. A Lyapunov function is constructed to analyze the stability of the feedback control law. Finally, the proposed control strategy is verified by simulations and experiments, which effectively reduces cross-coupling effects, suppresses noise, and improves the transient performance of the system.