感应电机模型预测直接速度控制

Model Predictive Direct Speed Control of Induction Motor

传统的模型预测转矩控制具有原理简单、动态响应快和控制灵活等优点,在感应电机高性能控制中得到了广泛研究。但是,现有方法一般通过转速外环来得到转矩参考指令,而转矩和磁链跟踪则通过内环的模型预测控制来实现。这种双闭环级联结构虽然保证了系统的稳定性,但存在内外环互相影响、调试参数较多等缺点。针对上述问题,舍去了传统控制方案中的双闭环串联结构,提出一种仅包括单个控制回路的模型预测直接速度控制方法。通过在价值函数中引入定子磁链误差和转子转速误差,实现了对不同时间尺度的转速和磁链的同时控制,具有结构简单、调试参数少等优点。另外,通过引入负载转矩观测器,提高了转速控制的稳态性能。相比传统模型预测转矩控制,提出的模型预测直接速度控制转矩和转速脉动显著减小,另外在全速范围具有更小的电流谐波,其有效性通过试验进行了验证。

The traditional model predictive torque control has the advantages of simple principle,fast dynamic response and flexible control.It has been widely studied in the high-performance control of induction motor.However,the existing methods usually obtain the torque reference command through the outer speed loop,while the torque and flux tracking are realized through the model predictive control of the inner loop.Although the cascaded double-loop structure ensures the stability of the system,it has some disadvantages,such as the interaction between the inner and outer loops,more debugging parameters and so on.To solve the above problems,the cascaded double-loop structure in the traditional control scheme is eliminated,and a model predictive direct speed control method including only a single control loop is proposed.By introducing stator flux linkage error and rotor speed error into the cost function,the simultaneous control of speed and flux linkage with different time scales is realized,which has the advantages of simple structure and few debugging parameters.In addition,the steady-state performance of speed control is improved by introducing load torque observation.Compared with the traditional model predictive torque control,the proposed model predictive direct speed control significantly reduces the torque and speed ripple.In addition,it has lower current harmonics in the full speed range.The effectiveness of the proposed method is verified by experiment results.