Abstract

The back EMF-based sensorless control of PMSMs is widely applied to the blowers and hermetic compressors of heating, ventilation and air-conditioning (HVAC) systems. For the sensorless control of PMSMs, a smooth transition from the I–f startup to the closed loop speed control with a rotor speed estimator is required. This paper proposes a smooth transition algorithm that can minimize torque and speed fluctuations under all load conditions. At the starting of a transition, the dq current based on the reference rotor position for I–f control is switched to the dq current with the estimated rotor position. The operating point of the dq current moves from I–f control to MTPA (maximum torque per ampere) operation, while the dq current follows a constant torque curve. Experimental results show that the torque and speed fluctuations under the proposed transition algorithm were significantly reduced under all load conditions.

中文翻译：

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负载下永磁同步电机的稳定无传感器过渡算法

摘要

基于反电动势的 PMSM 无传感器控制广泛应用于供暖、通风和空调 (HVAC) 系统的鼓风机和封闭式压缩机。对于 PMSM 的无传感器控制，需要从I-f启动平滑过渡到使用转子速度估计器的闭环速度控制。本文提出了一种平滑过渡算法，可以最大限度地减少所有负载条件下的扭矩和速度波动。在转换开始时，基于I-f控制参考转子位置的dq电流切换为具有估计转子位置的dq电流。dq电流的工作点从I–f控制移动到 MTPA（每安培最大扭矩）操作，同时dq电流遵循恒定扭矩曲线。实验结果表明，在所有负载条件下，所提出的过渡算法下的扭矩和速度波动均显着降低。