优先发表 | 四篇关于电机控制的文章

Abstract—For permanent magnet synchronous machine (PMSM), the machine model is critical to predict the operating states for motor control, which, however, can be greatly affected by system nonlinearities. Hence, this paper investigates accurate machine modeling for control and parameter estimation. In the proposed approach, the PMSM model with saturated inductances is used as the base model, and this paper investigates modeling and compensation of the offsets to the base model due to system nonlinearities such as saturation and core loss effects for accurate machine modeling and voltage prediction. Specifically, the offsets to the base model are modeled using nonlinear functions with variable coefficients to compensate saturation and core loss effect, which can achieve better accuracy without changing the model structure. A differential estimation model is derived to estimate the model coefficients from a small amount of measurements with simplified procedure. Moreover, the model offset calculation is both computation and memory efficient with simplified implementation. The contribution is to improve the machine model accuracy and achieve precise voltage prediction for practical applications. Experiments, comparisons and the application to temperature estimation are conducted on a test interior PMSM to validate the proposed approach.

Abstract—Vector-controlled AC motor drives utilize pulse width modulation (PWM) to synthesize the desired output voltage of the voltage source inverter (VSI). In space vector PWM (SVPWM) techniques, the average realization of the space vector applying the volt-sec balance principle results in an instantaneous error voltage that generates high frequency torque ripple. It may lead to an increase in motor vibration and acoustic noise. This article presents a high frequency torque ripple prediction model based on stator flux ripple and proposes a targeted designed variable switching frequency PWM (VSFPWM) strategy to diminish high frequency torque ripple. The switching frequency is dynamically adjusted according to the peak value of the predicted stator flux ripple to mitigate high frequency torque ripple. In contrast to existing strategies, the strategy outlined in this article directly suppresses high frequency torque ripple, thus remaining unaffected by inaccurate motor parameters. Additionally, due to the introduction of the power factor angle, the proposed strategy can better adapt to the full speed range operating conditions of the motor. Detailed simulations and experiments are provided to validate the effectiveness of the proposed strategy.

Abstract—The information of the field current is essential for the brushless synchronous starter/generator system, which determines the performance and health status of this system. However, since the field winding of the main machine is installed in the rotor part, the measurement of the field current in this brushless system seem impossible. Considering that, the field current might be affected by the rectifier mode, the field current estimation method in different rectifier mode is studied in this paper. The main exciter (ME) rotor currents were restructured based on the ME flux equations. With these restructured rotor currents, the field current in different rectifier commutation mode is analyzed, then the field current estimation method considering the rectifier mode can be obtained. The experiments in different rectifier modes are carried out to verify the proposed method.

Abstract—Coal mine conveyor belt and other low-speed large torque system, the torque density and torque stability of the motor requirements are higher, permanent magnet / magnet reluctance hybrid rotor double stator synchronous motor (PM/MRHRDSSM) is just adapted to this requirement, however, the traditional close winding single inverter vector control system control PM/MRHRDSSM provides large torque ripple, high speed fluctuation and large total harmonic distortion (THD) of the current, difficult to be used in actual production and life, this paper proposes a large torque open winding-permanent magnet / magnet reluctance hybrid rotor double stator synchronous motor(OW-PM/MRHRDSSM) based on SVPWM dual inverter control strategy, and analysis of open winding double inverter structure, and its voltage vector mathematical model, using the existing two-level inverter as a basis, the bilateral inverter separately discussed its role and control method, as well as the decomposition method of synthetic voltage vector and the inverter device in the small sector on-time, the end of this paper through simulation to compare the traditional close winding single inverter vector control system control PM/MRHRDSSM and the large torque OW-PM/MRHRDSSM based on SVPWM dual inverter control strategy to prove the effectiveness of the proposed method in reducing torque ripple, speed fluctuation and THD of current during motor operation.