Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title Signal Injection Sensorless Control Scheme of Synchronous Machine using Two Estimated Auxiliary Angles
Authors Hyun-Jun Lee ; Yongho Kim ; Jeong-Hoon Choi ; Young-Doo Yoon
Page pp.369-376
ISSN 1229-2214
Keywords High-frequency signal injection; Magnetic flux saturation; Signal injection sensorless control; Synchronous machine
Abstract This study analyzes the high-frequency (HF) current signal of an existing signal injection sensorless control (SISC) method and proposes a new SISC scheme for saturated synchronous machines by using two estimated auxiliary angles. The proposed method injects an HF voltage signal into the d-axis in the estimated injection coordinates and observes the induced HF current signal in the estimated observation coordinates. The key concept of the proposed method is that the center of two auxiliary angles is the estimated rotor angle, wherein the angle difference between the estimated rotor angle and each auxiliary angle is determined in accordance with dynamic inductance. The pure position error signal can be obtained using an appropriate angle difference, and thus, accurate position estimation is possible with the proposed method. This method only requires dynamic inductance; that is, finite element analysis or pretest with a position sensor or a rotor-locking device is not necessary. Experiments are performed on an 11 kW interior permanent magnet synchronous motor to verify the proposed method. Results proved that accurate position estimation is possible even under saturated conditions.