Abstract: Based on sliding mode variable structure theory, a design method for a speed regulator is proposed, which consists of a sliding mode controller. By rationally selecting relevant parameters c, α, and β, the sliding mode variable structure control strategy of the resulting closed-loop AC position servo system (position, speed, and current) exhibits advantages such as fast response speed and strong robustness. Simulation experiments using Matlab/Simulink are conducted to verify the results. Keywords: Induction motor; Vector control; Sliding mode variable control; Switching function ; ABSTRACT: Based on the control theory of sliding mode variable structure, this paper presents a design method for the speed regulator. The speed regulator consists of a sliding mode controller. By reasonably selecting the interrelated parameters c, α, and β, the control theory of sliding mode variable structure in an AC servo system with a closed-loop structure of position, speed, and current is constructed. This offers numerous advantages, such as faster response and better system robustness. A simulation experiment using Matlab is introduced. KEY WORDS: Induction motor; Vector control; Sliding mode variable control; Switching function; AC asynchronous motors are widely used due to their simple structure, high reliability, and large output torque. However, as a high-order, nonlinear, multivariable, and strongly coupled system, their control is challenging and difficult to adapt to applications requiring high control precision. With the continuous expansion of their application fields, there is an increasing expectation for a low-cost, high-performance control strategy to improve the performance of AC speed regulation systems. While traditional PID control methods can achieve good steady-state accuracy, their speed, anti-interference ability, and robustness to parameter perturbations are not ideal. Applying modern control theory to servo systems can enhance their robustness and improve their dynamic and static performance. In recent years, sliding mode variable structure control has shown promising prospects in AC servo systems. This paper proposes a new vector control strategy based on the principle of sliding mode variable structure control. Simulation results demonstrate the speed and effectiveness of this method. For details, please click: Research on Vector Control of Asynchronous Motors Based on Sliding Mode Variable Structure.