Torque ripple minimization control of permanent magnet synchronous motors for EPS applications

Jung

IET Electric Power Applications

et al. 2016

Electric machines are widely used across a variety of applications. In particular, the cogging torque of a permanent magnet (PM) synchronous motor is a significantly important characteristic in the application of electric power steering (EPS) systems. Accordingly, various optimal design methods are adopted to reduce the cogging torque for an EPS motor. However, in most cases, the measured cogging torque of the EPS motor is much greater than finite element method result, because the additional cogging torque harmonic components are generated by manufacturing tolerances. Especially, the specific harmonic components are produced due to magnetic unbalance by the asymmetry of motor shape which is caused by the tolerances in motor cores or PMs. These components are not eliminated by applying a skew. Thus, in order to reduce the effect of the tolerances, a robust design is needed. In this study, the effect of PM tolerances is studied, and Taguchi robust design is performed to enhance the motor quality regardless of the tolerances.

Section: Research Articlementioning

confidence: 99%

Taguchi robust optimum design for reducing the cogging torque of EPS motors considering magnetic unbalance caused by manufacturing tolerances of PM

Jung

IET Electric Power Applications

et al. 2016

“…In addition, by improving the structure of the permanent magnet, the cogging torque is effectively reduced by adopting the methods of segmentation, slotting, and changing the pole arc coefficient [7][8][9]. Moreover, some scholars have taken measures to reduce the cogging torque of the motor in the field of control [10,11]. Furthermore, numerous researchers have employed the response surface method (RSM) and multi-objective genetic algorithm (MOGA) to optimize the motor's design parameters, thereby enhancing its electromagnetic performance [12,13].…”

Section: Introductionmentioning

confidence: 99%

Multi-objective Optimization and Analysis of a Novel Permanent Magnet Synchronous Motor

Ran,

Wu,

Bai

et al. 2023

PIER C

In order to reduce the cogging torque and improve the back electromotive force (EMF) performance of the motor, a three-phase permanent magnet (PM) synchronous motor with magnetic pole eccentricity and slotting design is proposed in this paper. Firstly, the analytical expression for the cogging torque of the motor is derived based on the energy method, and the factors influencing cogging torque are analyzed. Subsequently, taking the cogging torque and the amplitude of the back EMF as the optimization objectives, the response surface method (RSM) and multi-objective genetic algorithm (MOGA) are combined to obtain the optimal values for the eccentricity distance of the PMs, slotting radius, and slot position. Finally, a finite element model is established for simulation comparison. The results show that compared with the traditional model, the optimized model effectively reduces the cogging torque while slightly sacrificing the back-EMF amplitude, and improves the sine degree of the no-load back-EMF.

“…Early EPS system mainly used DC motor as booster motor. With the development of motor technology, permanent magnet synchronous motor (PMSM) and AC induction motor were also successfully applied to EPS system [9]. TRW has developed the EPS system for commercial vehicles and studied the EPS system for heavy trucks and buses.…”

Section: Introductionmentioning

confidence: 99%

Design and Implementation of Controller for EHPS of Intelligent Electric Bus

Yuan

et al. 2019

IEEE Access

In order to meet the needs of bus electrification and intellectualization, a controller for the steering power system of an intelligent electric bus is studied in this paper. The contents mainly include: based on the structural principle and control strategy of the EHPS system, Luenberger observer is designed, which is applied to the sensorless control system of PMSM. Then, a controller with STM32F103zet6 chip as its core is designed and manufactured. The hardware design of the controller includes the minimum system circuit, power supply circuit, signal acquisition circuit, integrated driver module circuit, CAN communication circuit, fault and high temperature alarm circuit of the single chip computer; combining the design of each hardware part, the controller of EHPS system is made. In the aspect of software implementation, the control decision-making part, a motor drive control part, fault diagnosis, and transmission part are mainly designed. Finally, the bench test and vehicle test of the controller are carried out. The purpose of the bench test is to test the control effect of the controller on the motor. The bench test results show that the target speed response of the motor is fast and the output is stable. The controller developed in this paper realizes the control of PMSM. The purpose of the real vehicle test is to test whether the controller meets the actual application requirements of the steering power system of the vehicle. The actual vehicle test results show that the steering wheel's torque decreases obviously, and the steering power system has good power-assisting performance when the EHPS system controller works. With the increase of vehicle speed, the power-assisting torque decreases accordingly. EHPS system realizes the dynamic change of power-assisting and meets the requirements of the conventional power-assisting mode of the car. In addition, the controller can realize the active steering control by controlling the electric power assistant device, which provides a platform for the realization of lane auxiliary maintenance, automatic parking, unmanned driving, and other functions.INDEX TERMS Automotive engineering, electronic hydrostatic power steering, sensorless control system, Luenberger observer, intelligent electric bus, PMSM.