Abstract: We design a flux-weakening control method and sliding mode variable structure controller to improve the flux-weakening properties of the interior permanent magnet synchronous motor. We also investigate the low-and high-speed control strategy of the interior permanent magnet synchronous motor by combining maximum torque per ampere and vector control method. At the same time, during the flux-weakening control phase at high speed, the anti-windup integral controller is introduced into the current loop to prevent the current regulator from entering the saturated state. Simulation results show that the designed flux-weakening control method can effectively achieve flux-weakening control. The designed sliding mode controller and the introduced anti-windup integral controller can enhance system control performance.