Rotor Synchronous Motor Research Articles

Comparative Study between the Synchronous Motor to Permanent Magnets and Axial Flux (MSAP) and its Equivalent to Coiled Rotor (MSRB)

This work consists in conceiving of a coiled rotor synchronous motor equivalent to a permanent magnet axial-flux motor for electric vehicle by the joint method analytical / finite elements. An analytical model sizing motor is developed by the finite element method. A comparison between a 4 pairs of poles 6 teeth structure of a permanent magnet axial-flux motor and the studied motor is made in the goal to select the most effective structure for the same strength and same electric constant.

Circuits of a pulse-vector controlling alternate current motor drive

A system of classification for methods for pulse-vector controlling ac drives is presented. The resource and energy efficiency are considered in electric drives using pulse-vector control systems with wound rotor induction and synchronous motors. Various examples of pulse-vector control circuits are discussed. The control principles for each circuit are worked out, and instances of their application are given. The choice of the element basis of these circuits is grounded, and the advantages and disadvantages of each circuit are considered. The basic pulse-vector control circuits are compared in terms of the following parameters: the values of the maximum electromagnetic torque for the nominal motor torque and the torque pulses for the nominal motor torque. It is shown that application of pulse-vector control improves the energy- and cost-effectiveness of the electric drive, while using different circuits allows one to eliminate some of its disadvantages.

Excitation Synchronous Wind Power Generators With Maximum Power Tracking Scheme

This paper presents a novel excitation synchronous wind power generator (ESWPG) with a maximum power tracking scheme. The excitation synchronous generator and servo motor rotor speed tracks the grid frequency and phase using the proposed coaxial configuration and phase tracking technologies. The generator output can thus be directly connected to the grid network without an additional power converter. The proposed maximum power tracking scheme governs the exciter current to achieve stable voltage, maximum power tracking, and diminishing servo motor power consumption. The system transient and static responses over a wide range of input wind power are examined using simulated software. Experimental results from a laboratory prototype ESWPG demonstrate the feasibility of the proposed system.

A Stress Analysis Method for the Rotor Design of an IPMSM Considering Radial Force

In the design of the rotor of an interior permanent magnet synchronous motor (IPMSM), the bridge between the permanent magnets helps prevent the scattering of permanent magnets and pole pieces during high-speed operation. In the design of a motor, if the bridge is too thick, its performance will be largely degraded because of flux leakage. Additionally, if the bridge is too thin, its mechanical safety cannot be guaranteed. Thus, an accurate analysis method is required to determine the thickness of the bridge. Conventional stress analysis methods determine the thickness of the bridge by only considering the centrifugal force of the rotors. In this study, however, a method that additionally considers the radial force generated by the air-gap flux density based on the conventional methods is proposed and reflected in the design of a traction motor for electric vehicles. Finally, the validity of this study is verified through a reliability test related to high-speed operation.

2/4-POLE Split-Phase Capacitor Motor for Small Compressors: A Comprehensive Motor Characterization

Compressor electric motor drives play a key role in the energy consumption of residential refrigerators. Electrical efficiency, robustness to starting and overloads and speed variation range define the performance of compressor electric motor drives. Between the lowest cost fixed-speed split-phase capacitor grid-connected induction motor, with lower efficiency, and the higher efficiency grid-connected cage permanent-magnet (PM) rotor split-phase capacitor motor and the inverter fed variable speed PM synchronous motor of highest initial costs, we introduce in this paper a 2 speed grid-connected motor drive. The proposed topology uses a separate split-phase winding, cage-PM-4-pole rotor synchronous motor (PMSM) for low speed (4 poles) and a single-phase (main) winding for 2-pole operation. The tentative target is 85% efficiency at 50 W output for 4-poles (low speed) PMSM operation with good starting and about 60% efficiency in 2-pole (high speed) induction motor operation at 100 W, with smooth transients from low to high speed under full torque load. Circuit models for steady state and for transients with dedicated Matlab codes have been developed, with key FEM validation, to substantiate full scale experiments, and an optimal design methodology embedding both operation modes was put forward, as main theoretical contributions.

Определение углового положения ротора cинхронного двигателя в режиме векторно-импульсного пуска

This article discusses a method for sensorless determining the angular position rotor synchronous motors. It is known that there are difficulties in determining the angular position of the rotor in low speed range. Method using a high-frequency voltage injection, which allows to solve this problem is proposed in this article. The high-voltage signal processing circuit is examined and described in detail. A comparative analysis of the angular position of the rotor of a synchronous motor and the proposed sensorless method using a mechanical encoder is made. The obtained results suggest the possibility of using this method in the various systems of the drive.

Development of Wound Rotor Synchronous Motor for Belt-Driven e-Assist System

The automotive industry is showing widespread interest in belt-driven electric motor-assisted (e-Assist) systems. A belt-driven assist system (BAS) starts and assists the combustion engine in place of the conventional generator. In this study, a water-cooled wound rotor synchronous motor (WRSM) for the e-Assist system was designed and analyzed. The performance of the WRSM was compared with that of an interior permanent magnet synchronous motor (IPMSM). The WRSM efficiency can be improved for the BAS by adjusting the field flux at high speeds. The field current map to obtain the maximum efficiency based on the speed and torque was developed. To control the field flux via field current control in the WRSM, a general H-bridge circuit was added to the WRSM inverter to get the rapid current response in the high-speed region; the characteristics were compared with the chopper circuit. A WRSM developed for the belt-driven e-Assist system and a prototype 115 V power electronic converter to drive the WRSM were tested with a 900 cc combustion engine. The test results showed that the WRSM-type e-Assist system had good characteristics and could successfully start and assist the 900 cc combustion engine.

Optimization Design of Auxiliary Grooves on Rotor of Permanent Magnet Synchronous Motor for Electric Vehicles

In order to reduce the influence of the harmonics of the air-gap magnetic field on PMSM performance, in this paper, the method which is to add auxiliary grooves in the rotor surface is proposed to optimize the air-gap magnetic field of PMSM and reduce the iron loss, torque ripple and noise-vibration caused by the harmonics. During the process, the orthogonal experimental method and the time-stepping FEM were used to optimize the structure of the grooves. Analyzed and compared the test-data and the calculated data,it shows that this method can largely improve motors performance.

계자전류 조합에 따른 ISG용 권선형 동기전동기의 설계 및 특성분석

In this paper, design of Wound Rotor Synchronous Motor(WRSM) for Integrated Starter and Generator(ISG) is performed based on Finite Element Analysis(FEA). WRSM can control not only magnitude and phase of armature current, but also field current. Thus, various control methods can be considered. Since driving characteristic of WRSM depends greatly on the control method, characteristic analysis accoding to possible driving current combination is reguired. Especially in high speed region, the control method that reduces unnecessary d-axis current by reducing field current is possible, which is similar to field weakening control. By the current combination reducing field and d-axis current, the design minimizing copper loss to increase efficiency on identical driving point is possible. In this paper, high efficient WRSM is designed applying the current combination which can minimize copper loss on each driving point.

Высокочастотная инжекция сигналов при бездатчиковом методе определения углового положения ротора синхронного двигателя

The method of sensorless control the angular position of the rotor synchronous motors was viewed in this paper. The pros and cons of the use of such systems to replace systems using rotor position sensor were presented. The advantages of sensorless motor control systems: improve the reliability of the electric system, reduce the cost of the drive, improve the weight and size. Application field of sensorless drives was given. The analysis of possible ways to control the angular size of rotor was made. Advantages and disadvantages were presented. There are a number of methods of sensorless determination of the angular position of the rotor, but each of them has one significant drawback according to which the angular position of the rotor cannot be determined at low and zero motor speeds. The high-frequency injection, allowing the expense of imposing an additional signal to eliminate the identified problem was considered. The main idea of this method is to initiated a voltage or current, which contain information about the position of the rotor, by high frequency injection. he main advantage of this approach is that it allows to evaluate the position of the rotor at zero and low speed, it was not possible in earlier approaches. A mathematical model of the heterodyning for acquiring the specialized frequency content of the signal was introduced .

ISG용 권선형 동기기의 설계 및 IPMSM과 특성 비교

This paper deals with Wound Rotor Synchronous Motor (WRSM) purposely designed for Integrated Starter and Generator (ISG) installed in 42V automotive electrical system. Not only design objective and specifications of WRSM, but its adaptive design to minimize torque ripple and back-EMF Total Harmonics Distortion (THD) are considered. Furthermore, design characteristics of designed prototype have been investigated numerically in terms of torque, back EMF, loss, and efficiency, which are verified by performance comparison with Interior Permanent Magnet Synchronous Machine based on Finite Element Analysis (FEA).

고속 운전 시 WRSM의 성능 향상 및 IPMSM과 비교

This paper shows an improvement of the WRSM (Wound Rotor Synchronous Motor) by satisfying the voltage limit condition at high speed. After that, it compares the performance of the improved WRSM to that of the IPMSM (Interior Permanent Magnet Synchronous Motor). The comparison has been made under the condition where the dimension of the motor is identical to that of the IPMSM, having the rotor switched to a wounded rotor form. Moreover, this paper compares the Basic Model of the two motor, and estimates the parameters of the WRSM, thereby proposing the method to improve high speed performance. Furthermore, this paper presents the feasibility of switching the conventional motor into rare-earth-free motors for traction purpose.

Position and Speed Detection of Synchronous Motor Rotor

This article describes a method to detect the position and speed in a rotary transformer pole AC synchronous motor. This method gives the pole position and velocity signal demodulation circuit and analyses the demodulation principle. After practical testing, this approach is reliable with high detection accuracy. Therefore, it is fully able to meet the needs of CNC machine tools with high performance in AC server system.

집중권을 시행한 영구자석 매입형 동기전동기의 철손 저감

집중권 방식의 견인용 영구자석 매입형 동기전동기(IPMSM)는 출력밀도의 관점에서 우수하나 심각한 영구자석 와전류 손실을 가지고 있다. 본 논문에서는 영구자석 매입형 동기전동기의 자기적 특성을 분석하여 V-타입 회전자 영구자석의 각도와 폭을 변경함으로써 철손을 최소화하는 최적설계를 수행하였다. 자성체의 비선형성을 고려하기 위하여 자기등가회로법 대신 유한요소법을 이용하였으며, 각 파라메타가 영구자석에 발생하는 철손에의 영향 및 파라메타간의 교호작용을 파악하기 위하여 시뮬레이션 기반의 실험계획법을 사용하였다. 이를 통하여 모터의 성능을 유지하면서 철손을 상당히 줄인 집중권 방식의 영구자석 매입형 동기전동기의 최적설계를 반응표면법을 이용하여 도출하였으며, 유한요소법을 이용하여 이를 검증하였다. Interior Permanent Magnet Synchronous motors (IPMSM) with concentrated winding are superior to distributed winding in the power density point of view. But it causes huge amount of eddy current losses on the permanent magnet. This paper presents the optimal permanent magnet V-shape on the rotor of an interior permanent magnet synchronous motor to reduce the core losses and improve the performance. Each eddy current loss on permanent magnet has been investigated in detail by using FEM (Finite Element Method) instead of equivalent magnetic circuit network method in order to consider saturation and non-linear magnetic property. Simulation-based design of experiment is also applied to avoid large number of analyses according to each design parameter and consider expected interactions among parameters. Consequently, the optimal design to reduce the core loss on the permanent magnet while maintaining or improving motor performance is proposed by an optimization algorithm using regression equation derived and lastly, it is verified by FEM.

An adaptive control strategy for wound rotor synchronous machines

SUMMARYThis paper addresses the problem of controlling wound rotor synchronous motors in association with their power conversion components, i.e. AC/DC rectifiers and DC/AC inverters. Considering the whole association, ‘converter‐motor’ makes it possible to account, in addition to motor speed regulation, four other important control objectives such as power factor correction with respect to the supply net and DC link voltage regulation. To achieve these objectives, an adaptive control strategy is developed, based on a nonlinear model of the whole ‘converter‐motor’ association. Adaptation is motivated by the uncertain nature of some motor characteristics, especially the mechanical parameters. The closed‐loop system stability and performances are formally described using averaging theory. Copyright © 2012 John Wiley & Sons, Ltd.

Simulation and Research of Control-System for PMSM Based on Sliding Mode Control

In this paper, permanent magnet synchronous motor rotor flux oriented control strategy is studied, for the key issues of vector control is to observe the rotor flux, the control system is given based on sliding mode observer, and the sliding mode rotor flux observer is designed, with MATLAB/SIMULINK simulation, the results of simulation show that the system with wide speed range, has a good dynamic and static performance.

Optimization of PMSM Sensorless Control Based on Improved PSO Algorithm

For the problem that manual adjustment of the parameters of controller in sensorless control system costs too much time, manpower and always can not get a good result, a new method based on improved particle swarm optimization algorithm is proposed to optimize the parameters. The improved algorithm is based on the standard particle swarm optimization with the simulated annealing algorithm and chaotic search brought in. The speed of motor is estimated by the extend Kalman filter. The error between measured speed and estimated speed of the permanent magnet synchronous motor rotor is used as the fitness function in order that the parameters in the covariance matrix is adjusted.The result of simulation indicates that high estimation precision can be got and the motor represents steadily with few of ripple of the actual speed.With this method, the time of adjustment is reduced and manpower is saved. In addition, the validity of the method is proved in experiment with dSPACE.

Research on Operating Performance for Hybrid Rotor Synchronous Motor

This paper with an open-loop V/f control mode of inverter supply, searched for the causes of the oscillation using small signal analysison the axially-laminated anisotropic (ALA) rotor and hybrid rotor (ALA-SPM two-part) motor, and analyzed operating performance of themotors with inertial damper on the same shaft. Results show that the negative electromagnet damping coefficient can be the key point toresult in the oscillation; the electromagnet damping coefficient can increase with the increasing new variable k, the fraction length of SPMpart, the maximum load of the motors and the stability can be improved. The stability of the system and the dynamic performance can bebetter with reasonable viscous damping coefficient of inertial damper, the motors can adequately develop their output torque capability,and improve operating performance. Ill. 11, bibl. 11, tabl. 3 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.113.7.603

Design and determination of stator geometry for axial flux permanent magnet free rod rotor synchronous motor

During designing a new axial flux permanent magnet free rod rotor synchronous motor, it is important to know before hand in which phase the largest angular velocity can occur, what is the ways to reduce the power consumption, how to achieve to increase or decrease the rotation speed by changing the core geometry. Therefore, presenting these preliminary information that are necessary for the design of a free rod rotor synchronous motor to the researchers is the aim of this work. In this respect, this study presents the design and geometrical dimensions of the stator for a new synchronous motor which is an axial flux permanent magnet free rod machine with three, four, five and six phases. This type of motors are an innovative approach especially for the applications used in industrial stirrers. Each type of stator is designed such that it has an appropriate number of phases. The rotating magnetic field over the stator is established by a PIC based microcontroller feeding the interface circuit to the stator wounds. The maximum angular speeds of bar magnet rotors with four different lengths and masses are calculated theoretically and determined experimentally. In addition, the effects of the distance between the rotor and stator, the angular speed of the rotor within the limits of the operation, and the volume of the liquid to be stirred to the power applied are investigated. Furthermore, the effects of the lengths and angular speeds of the bar magnet rotors to the distance between the rotor and stator are determined. In the light of the information obtained and taking into account the power used, the most appropriate parameters and variables such as the stator geometry changing with the phase used, the length of rotor, the distance between the rotor and stator and the angular speeds of rotor are determined.

Reactive Power Management for Wind Electric Generator

Energy in the Wind is converted into Rotary Mechanical Energy by the Wind turbine. Most of the Wind Electric Generators are having Induction Motor, (Asynchronous Motor) with constant speed and drawing more Reactive Power from the Grid, during starting / low wind period. This thesis emphasized the need of replacing the existing conventional Asynchronous Induction motor of Constant Speed by Wound Rotor Synchronous Induction motor of variable speed, namely, Doubly Fed Induction Generator (DFIG). The control principle is either the Direct Torque Control (DTC) method, Or, Two - axis Current Vector Control Method. The Direct Torque Control Method is more effective than the two axis current vector control method, for Reactive Power Management for Wind Electric Generator. The minimum usage of only about 30% of Power Electronics results in considerable cost savings and reduction of harmonics when compared with Fully Converter Wind Electric Generators.