Title :
Pulsating Signal Injection-Based Axis Switching Sensorless Control of Surface-Mounted Permanent-Magnet Motors for Minimal Zero-Current Clamping Effects
Author :
Choi, Chan-Hee ; Seok, Jul-Ki
Author_Institution :
Sch. of Electr. Eng., Yeungnam Univ., Kyongsan
Abstract :
In this paper, we propose an injection-based axis switching (IAS) sensorless control scheme using a pulsating high-frequency (HF) signal to minimize position detection error and velocity estimation ripple resulting from the zero-current-clamping (ZCC) effect for surface-mounted permanent-magnet motors. When a pulsating carrier-signal voltage is injected in an estimated synchronous frame, the envelope of the resulting HF current measured in the stationary reference frame follows an amplitude-modulated pattern. Using this information, the IAS technique allows one to avoid multiple zero crossings of HF currents by adjusting the current phase angle according to the load condition. At no-load condition, the pulsating voltage is injected only on the d-axis, while the d-axis current is controlled to a certain nonzero value. Under a load condition, the injection voltage is switched to the q-axis, while the d -axis current drops back to zero. Thus, the proposed sensorless control enforces a much better estimation performance in a region of ZCC without a predefined offline commissioning test than the standard pulsating injection scheme. Experiments illustrate the effectiveness of the proposed method in suppressing the estimation error caused by the ZCC disturbance and in extending the system bandwidth.
Keywords :
electric current control; machine control; permanent magnet motors; amplitude-modulated pattern; axis switching sensorless control; current phase angle; minimal zero-current clamping effects; position detection error; pulsating carrier-signal voltage; pulsating high- frequency signal; pulsating signal injection; standard pulsating injection scheme; stationary reference frame; surface-mounted permanent-magnet motors; synchronous frame; velocity estimation ripple; Amplitude estimation; Clamps; Current measurement; Error correction; Estimation error; Hafnium; Permanent magnet motors; Sensorless control; Voltage control; Zero voltage switching; Estimated position error and velocity ripple; injection-based axis switching (IAS) sensorless control; pulsating high-frequency (HF) signal injection; zero-current-clamping (ZCC) effect;
Journal_Title :
Industry Applications, IEEE Transactions on
DOI :
10.1109/TIA.2008.2006350