【摘要】 针对永磁同步电机电磁转矩与负载角之间强耦合及非线性的关系,并就传统直接转矩控制容易失步的问题,该文提出了一种负载角限制的策略。基于直接转矩控制基本原理对电机失步原因进行研究,重点分析负载角与转矩之间的关系,提出了对负载角限制避免电机失步的控制思想。详细介绍了基于永磁同步电机的模型预测数学模型,考虑到消除系统预测误差加入了控制延时补偿。最后通过评价函数有效地限制了电机转矩和磁链脉动,直接限制负载角确保了电机的稳态运行。通过仿真分析可看出该文提出的方案有效可行,在保持快速响应的情况下,降低了转矩和电流脉动,避免了电机失步的风险。更多还原

【Abstract】 In view of the strong coupling and nonlinear relationship between the electromagnetic torque and the load angle of permanent magnet synchronous motor,and the problem that the traditional direct torque control is easy to step out,a load angle limiting strategy is proposed. The traditional direct torque control principle is analyzed to find the causes of motor out-of-step. Based on the analysis of the relationship between the load angle and the torque,the control idea of limiting the load angle to avoid motor out-of-step is put forward. The model prediction mathematical model based on permanent magnet synchronous motor is introduced in detail,and the control delay compensation is added to eliminate the system prediction error. Finally,the evaluation function is used to limit the torque and flux ripple effectively,which also directly limits the load angle and makes the motor run in a stable state. Through the comparison of simulation models,it can be seen that the proposed scheme is effective and feasible. Under the condition of maintaining fast response,the torque and current pulsation are reduced,and the risk of motor out-of-step is avoided.更多还原