Daigo Kaneko

Initial rotor position estimation of the interior permanent magnet synchronous motor

A new method of the rotor position estimation is proposed for interior permanent magnet synchronous motors. The proposed method for the initial rotor position estimation consists of two parts: one estimates the rotor position of the magnetic pole; the other determines the direction of the magnetization at the estimated position at the same period. The basic idea and the experimental results are discussed in this paper.

Adaptive back EMF parameter adjustment of simplified vector control for position sensorless permanent magnet synchronous motors

A previously reported simplified vector control for position-sensorless permanent magnet synchronous motors can be affected by errors in setting the motor parameters, because no feedback compensator is used. We examine the effects of errors on the steady-state performance of these motors in this paper. It was found that the current amplitude increases when a parameter error is given and the effect of a back EMF parameter error is especially large. We propose a new back EMF parameter adjustment method based on these results. We determined from our simulation and experimental results that the proposed method can compensate for the current increase caused by the parameter error. A theoretical analysis showed that the proposed method is affected by only the daxis inductance parameter Ld. Therefore, even if there are errors in the other motor parameters, the motor current of the constant load condition is minimized by using the proposed method.