直驱式永磁曳引系统无称重传感器起动控制策略

Weight-transducerless Starting Torque Control Strategy of Direct-drive Permanent Magnet Traction System

无齿轮直驱式永磁曳引系统已成为现代电梯的发展趋势。为了提高电梯永磁曳引系统的性能,提出一种基于无静差模型预测控制的无称重传感器起动转矩控制策略。针对直驱曳引系统机械模型不确定、非线性和强扰动负载特性引起的预测模型失配问题,在预测模型中引入模型校正环节以克服模型失配问题。在预测模型中加入估计等效扰动信息来消除零伺服过程的速度静差,并将转速估计量引入到速度预测环节作为速度预测初值,从而无需在价值函数中再对预测速度进行校正。所研究的无称重传感器控制策略能够在抱闸释放瞬间准确控制电磁转矩,快速追踪不确定性综合扰动转矩,有效减小轿厢倒溜距离,并避免机械振动,从而提高了乘梯舒适性。最后,仿真和实验结果均验证了所提出无称重传感器控制方法的有效性。

Direct-drive permanent magnet traction system has become the trend of modern elevators. To improve the starting performance of permanent magnet traction machine without a weight transducer in the gearless elevator,a starting torque strategy based on off-set free model predictive control is proposed. In order to overcome the mismatch of predictive model causing by the uncertainty and nonlinearity of the mechanical model, as well as intense disturbance, a model corrector added to the predictive model is used to make the mismatched predictive model matched. The speed offset can be eliminated by adding the estimated equivalent disturbance to the predictive model during the zero-servo operation. The estimated speed is used as an initial value in speed prediction. Therefore, there is no need to correct the predictive speed error in cost function. Electromagnetic torque generated by the motor can quickly balance the unknown disturbance torque to minimize sliding distance and avoid mechanical vibration by using this proposed method. So it can achieve superior riding comfort. Finally, both the simulation and experimental results are provided to verify that the proposed strategy can achieve shorter sliding distance, smaller sliding speed and faster dynamic response.