针对真空泵用多台屏蔽电机起动、突加随机扰动、突加周期性负载及单/多电机不同时刻故障停机过程，设计了模式切换与位置补偿偏差耦合同步控制系统，创新性地在速度补偿器中引入位置补偿器，同时在故障瞬间将偏差耦合控制方式切换为主从控制。将所提出的控制系统与传统的虚拟电机控制系统进行了对比。结果表明：当发生单电机故障以及双电机不同时刻故障时，在相同的模式切换和位置补偿条件下，所提出的控制系统位置误差分别为4.6°和4°，在5°的误差允许范围内，而传统虚拟电机控制系统的位置误差分别为15°和20°。

For the multiple-canned-motor system used for vacuum pumps, fault shutdown may occur under different conditions such as starting, sudden random disturbance, sudden cyclic load, single motor failure, and multi-motor asynchronous failure. Aiming at this problem, a mode switching and position compensation deviation coupling synchronous control system is designed. The position compensator is innovatively introduced into the speed compensator and the deviation coupling control mode is switched to master-slave control at the moment of fault shutdown. The proposed control system is compared with the traditional virtual motor synchronous control system. The results show that for single motor failure and two-motor asynchronous failure, after mode switching and position compensation, the position errors of the proposed control system are 4.6° and 4°, respectively, which are smaller than the position error tolerance value of 5°. In comparison, the position errors of the traditional virtual motor control system are 15° and 20°, respectively.

国家重大科技专项项目（2017ZX02201005-0025）