Magnetising method for speed sensorless controlledinduction motor drives

Magnetization of speed sensorless squirrel-cage induction generator for wind power application using a phase-locked loop

“…[16][17][18][19][20] show that the PLL-based position controller will detect synchronous frequency and magnetize the machine regardless of the machine parameter variations. Based on the presented experimental results, it can be concluded that the proposed magnetization technique is insensitive to the R s , R r , L s and L r parameter changes.…”

“…Hence, in order to achieve a successful magnetization using voltage-based flux estimation methods, these methods have to be modified. It is interesting to note that, although this subject matter is very attractive, little has been published about it [20][21][22]. The methods proposed in [20][21][22] require transient excitation of the machine or injection of the DC stator current component to identify the necessary speed without using a speed sensor.…”

“…It is interesting to note that, although this subject matter is very attractive, little has been published about it [20][21][22]. The methods proposed in [20][21][22] require transient excitation of the machine or injection of the DC stator current component to identify the necessary speed without using a speed sensor. However, commercially available speed sensorless drives contain a flying start function and are thus able to determine the rotor speed of a non-magnetized induction machine during the start-up.…”