Rotor position and velocity estimation for a salient-pole permanent magnet synchronous machine at standstill and high speeds

Abstract

Abstract-This paper addresses self-sensing ("sensorless") control of salient-pole permanent magnet synchronous motors (PMSM's). The major contribution of this work is the introduction of a simple-to-implement estimation technique that operates over a wide speed range, including zero speed. The technique achieves simplicity by decoupling the inherent cross-coupling in PMSM's. The technique utilizes the dependence of inductance on rotor position in interior permanent magnet machines to produce position and velocity estimates both for field orientation and for all motion control of the drives. The technique functions in a manner similar to a resolver and resolver-to-digital converter (RTDC) sensing system, whereby in the proposed technique the motor acts as the electromagnetic resolver and the power converter applies carrier-frequency voltages to the stator which produce high-frequency currents that vary with position. The sensed currents are then processed with a heterodyning technique that produces a signal that is approximately proportional to the difference between the actual rotor position and an estimated rotor position. This position error signal and a torque estimate are then used as inputs to a Luenberger style observer to produce parameter insensitive, zero lag, position and velocity estimates.Index Terms-Permanent magnet motor control, self sensing, sensorless control, sensorless tranducerless field orientation, sensorless vector control, transducerless control. NOMENCLATURE SuperscriptŝEstimated quantities. Commanded quantities. Stator reference frame. Rotor reference frame. Estimated rotor reference frame.

A Simple Strategy for Sensorless Speed Control for an IPMSM During Startup and Over Wide Speed Range

“…Therefore, the high-frequency (HF) signal injection method is introduced. Because the HF signal injection method does not estimate the current and back-EMF, it exhibits great performance at startup and in the low-speed region [12][13][14][15][16]. In contrast to the back-EMF and observer-based methods, the performance becomes worse when the motor operates at a high speed.…”

“…The general HF injection methods use many filters such as a band pass filter (BPF) and low pass filter (LPF) to eliminate the fundamental frequency and extract the HF signal and rotor position [4,[13][14][15]. As the number of filters increases, the time delay also increases, which causes an error in the estimated rotor position.…”

“…θ θ -contained in the d-axis current is controlled to zero by the controller. When the error is controlled to be zero, the rotor position can be estimated [14][15][16].…”

Simulation of Synchronous Motor Power driven System for EPS Based on SVPWM-DTC

“…Pairwise sequence of the power transistor conduction is generally:120° electrical angle, the upper and lower leg of the three-phase power of the same bridge arm of the tube,They can not be turned on the same time, otherwise it will form a power short-circuit, it is generally by inserting the dead time to avoid , insert the dead time is generally about 5-20 us . ψ ψ [4] . SVPWM control signals can be generated through inverse Park Transformation , and then drive PMSM motor in EPS.…”

Comparison of two position and speed estimation techniques used in PMSM sensorless vector control

“…For consistent starting, a separate technique was needed, often using the inductance-variation approach [9] or the high frequency signal injection [10,11]. In fact, a closed loop smooth and reliable starting can only be achieved when information regarding the absolute rotor position is available.…”