Sensorless Control of Short Stator Permanent Magnet Synchronous Linear Machines – A Renewed Approach

Inhalt:
This paper presents a novel two-degree-of-freedom (2DoF) sensorless position control scheme for short stator permanent magnet synchronous linear machines (PMSLM) using test current signal injection. Asymmetrical winding and saturation cause the occurrence of differential cross-coupling inductances and as a result the estimated primary position deviates from the real value. These inductances have to be compensated for to overcome this problem. For that a flatness based current feed forward control is proposed. The control signals of the current controller are used to estimate the primary position and speed. The 2DoF control is applied to the superimposed speed and position control loops, too.