基于AC-DC-AC的异步电机系统积分反步和滑模控制

为了实现基于AC-DC-AC的异步电机系统四象限运行、能量双向流动、网侧单位功率因数、直流母线电压可控,采用了积分反步与滑模控制。当负载转矩较大范围变化时,直流母线电压发生较大的波动,网侧子系统电流内环采用电容电流控制,直流母线电压快速恢复恒定。针对起动时电压超调问题,提出电压软给定的方法,抑制了较大超调。针对负载转矩未知,采用滑模观测器。仿真结果表明,该方案下的系统性能较好。

Integral Backstepping and Sliding Mode Control of Asynchronous Motor System Based on AC-DC-DC Converter

To realize four-quadrant operation,bidirectional energy flow,grid-side unit power factor and controllable DC bus voltage of AC-DC-AC converter based asynchronous motor systems,integral backstepping and sliding mode control were adopted.The DC bus voltage fluctuates greatly when the load torque changes in a wide range,a capacitor current control was used in the inner loop of the grid-side subsystem current,and the DC bus voltage quickly returns to a constant level.Aiming at the problem of voltage overshoot at startup,a method of voltage soft setting was proposed to suppress the large overshoot.Aiming at the unknown load torque,sliding mode observer was used.Simulation results showed that the system has good performance with this scheme.