Comparative Study Of Back EMF Based Sensorless Control Methods For Dual Three-Phase PMSM

Abstract

Multiphase electrical machines have gained increased attentions recently due to its fault tolerance capability which is of great importance for more-electric aircraft application. This paper studies sensorless control of a highspeed dual three-phase electrical machine for turboprop aircraft green taxiing motor and engine generator applications. After introduction of a detailed mathematical model of a dual three-phase permanent magnet machine, two different types of back EMF based sensorless control are compared in this paper. The first method uses a phase-locked-loop (PLL) type speed and rotor position estimator and the other uses a Luenberger observer estimator. The effectiveness of these two different methods is demonstrated using simulations in the Matlab/Simulink environment. The comparison studies show that Luenberger type estimator has better dynamic performance but suffers high frequency noise in the estimated speed error and requires the use of machinal parameters. In contrast, PLL type estimator has inferior but acceptable performance. Its low-pass characteristics frees it from the high frequency noise. Moreover, it does not require the use of mechanical parameters.

Comparative Study of Sensorless Methods Based on Sliding Mode Observer for Dual Three-Phase Permanent Magnet Synchronous Machine

“…Each set is designed to shift from the other by 180 electrical degrees. According to the mathematical model of the machine detailed in [5], the voltage equation in stationary frame can be deduced as:…”

“…Thus, the rotor position error is proportional to ∆ and a PI controller is applied to correct the position estimation error and make the estimated result converge to the reference one. The details of the design of PLL based estimator could be found in the previous work of author [5].…”

“…To combat the size limitation of installing mechanical speed/position sensors in the airplane gear box, sensorless control is adopted since it could save space as well as installation cost and improve the reliability of the system simultaneously. Sensorless control methods can be categorized into two major groups [4]: the back EMF based method [5] and the saliency tracking based method [6]. Among various methods, the sliding-mode control (SMO) method, as a practical instance of rotor speed/position estimation, is widely used because of its simple algorithm and robustness [7].…”

Fundamental PWM Excitation Based Rotor Position Estimation for a Dual Three-Phase Permanent Magnet Synchronous Machine

“…The first category makes use of the fundamental model of the DTP-PMSM to estimate the rotor position or speed, e.g. [6][7][8][9][10][11][12][13].…”

“…Some researchers resorted to different observers or the Kalman filter (EKF). For example, in [11], two methods, i.e. PLL observer and Luenberger observer were compared.…”