Sensorless initial rotor position estimation of surface permanent magnet synchronous motor

Abstract

This paper describes an initial rotor position estimation of surface permanent magnet synchronous motor without sensor. The estimation is performed by using the nonlinear magnetization characteristics of the stator core caused by the magnet of the rotor. The validity of the proposed estimation method is verified by the experiment.

A Study on Startup-Characteristic of Sensorless Controlled IPMSM Employing Sliding Mode Observer

“…이에, 정지 상태에서 위 치정보를 얻기 위한 고주파 주입법, 전압펄스를 이용 한 방법이 있다 [4][5] [6] . 하지만, 이런 방법들은 계산이 어렵고 구현이 복잡하여 아직 산업체에서 널리 사용되 지 못한다.…”

A New Open Loop Approach for Identifying the Initial Rotor Position of a Permanent Magnet Synchronous Motor

“…On the other hand, including much of calculus, the identifying algorithms in some works above are very complex [16,17,[21][22][23][24][25][26][27][28]30]. In this paper, a new open loop approach is proposed to identify initial rotor position of a PMSM with current type driver, which can work well even when a constant load torque is being applied, and the identifying algorithm is very simple and quick.…”

“…An appropriate voltage pulse width signal is selected and applied to each phase winding of PMSM to partially saturate the stator iron to get the absolute position of the rotor at standstill in [22]. A search algorithm for an optimum voltage vector that uses effective magnetic saturation without rotating the rotor was introduced in [23]. Magnetic axis without polarity was estimated via an indirect flux detection by online reactance measurement and the polarity was detected by finding minimum inductance on the estimated magnetic axis in [24].…”

Initial rotor position estimation and sensorless direct torque control of surface-mounted permanent magnet synchronous motors considering saturation saliency

“…According to the types of the applied signals, the inductance variation detection technique can be broadly categorised as injecting either a high frequency signal [3][4] or a special pulse width modulation (PWM) signal [5][6][7][8]. The special PWM signal includes a series of voltage pulses [7][8].…”

“…However, for the surface mounted PMSM, which does not have significant structural saliency, it has been a difficulty to detect the rotor position at zero or low speeds under load conditions. Numerous efforts have been made in this field by injecting signals to amplify the saturation saliency [3][4][5][6][7][8].…”