Stabilization Control in Low-speed Region in Speed Sensorless Vector Control

在异步电动机无速度传感器矢量控制中，在低速区不可避免地会产生不稳定现象。本研究的目的是利用磁通传感器从根本上克服这种不稳定现象。首先，我们用通用感应电机（2.2kw， 4极）进行实验，明确感应电机的轭架磁通特性。在感应电机的轭架上做了一个直径为15mm，深度为5mm的磁通检测孔。采用零磁场型磁通传感器检测孔内磁通。澄清了以下事情。首先，当磁通传感器的位置发生变化时，测量磁轭内的磁通大小。因此，在分离时，磁通的大小在双曲线函数中从感应电动机的定子槽处衰减。此外，感应电机磁通检测中还存在一定的三次谐波。然而，本文的研究表明，利用本方法对感应电机进行磁通检测是完全可能的。我们提出了一种新的控制方法，即利用上述磁通传感器进行无速度传感器矢量控制。计算机仿真验证了该控制方法的有效性。结果表明，该控制方法克服了低速区域的不稳定现象。

In the speed sensorless vector control of induction motor, an unstable phenomenon is inevitably generated in a low-speed region. The purpose of this research is to conquer this unstable phenomenon fundamentally by using the magnetic flux sensor.First of all, we experimented with a general-purpose induction motor (2.2kw, 4poles) to clarify the characteristic of the yoke magnetic flux of the induction motor. The hole for the magnetic flux detection of 5mm in the diameter 15 mm in depth was made in the yoke of this induction motor. The magnetic flux in this hole was detected by zero magnetic field type magnetic flux sensor.The following thing was clarified. First of all, when the position of the magnetic flux sensor was changed, the magnitude of magnetic flux in the yoke was measured. As a result, it has been understood that the magnitude of the magnetic flux attenuates from the stator slot of the induction motors in the hyperbola function while parting. Moreover, some third harmonic remains in the magnetic flux detection of the induction motors. However, it has been clarified that the magnetic flux detection of the induction motors is very possible by the method of this research.We proposed a new control method, which is a speed sensorless vector control with the magnetic flux sensors mentioned above. The effectiveness of this control method was verified by computer simulation. As a result, the unstable phenomenon in a low-speed area was overcome by this control method.