Field Excitation Flux Switching Motor Research Articles

Electromagnetic Performances and Main Parameter Sensitivity Effect on Unbalance Magnetic Flux in a New Single-Phase FEFSM with Segmental Rotor

Three-phase field excitation flux switching motor (FEFSM) with salient rotor structure has been introduced with their advantages of rotor easy temperature elimination and controllable FEC magnetic flux. Yet, the salient rotor structure is found to lead a longer magnetic flux path between stator and rotor parts, producing a weak flux linkage along with low torque performances. Hence, a new structure of single-phase FEFSM using segmental rotor with non-overlap windings is proposed with advantages of shorter magnetic flux path, light weight and robust rotor structure. Analysis on fundamental magnetic flux characteristics, armature and FEC magnetic flux linkages, cogging torque, back-Emf, various torque capabilities, refinement of unbalance magnetic flux, and torque-power versus speed characteristics are conducted using 2D FEA through JMAG Designer version 15. The results show that magnetic flux amplitude ratio has been improved by 41.2% while the highest torque and power achieved are 1.45 Nm and 343.8 W, respectively.

Optimal design of single-phase 12S-6P FEFSM using segmental rotor and non-overlap windings

<span>Recently, a three-phase Field Excitation Flux Switching Motor (FEFSM) using salient rotor has been introduced, suitable for high torque, high power as well as high speed diverse performances due to their advantages of easy rotor temperature elimination and controllable field excitation (FE) flux. However, existing FEFSMs are found to have low torque performance as the salient rotor structure has caused longer flux path, and consequently weak flux linkage. Therefore, a new structure of a single-phase FEFSM using segmental rotor and non-overlap windings is proposed. There are two valuable findings found in this topology, first is less copper loss due to the non-overlap windings between armature and FE coils, and secondly the segmental rotor structure has produces shorter flux path to produce high torque, less rotor weight as well as robust rotor at high speed condition. Flux linkage, back-emf, average torque and output power characteristics of the initial and optimized designs have been investigated and compared using 2D Finite Element Analysis (2D-FEA) through JMAG Designer version 15. Based on the 2D-FEA analysis, the average torque has increased by 81.3% to 1.65 Nm, while the output power of 466.5 W, increased of 68.2%. In conclusions, a FEFSM using segmental rotor and non-overlap windings is considered as the best single-phase motor due to their optimal performances and less copper loss.</span>

Preliminary Design Analysis of a New Field Excitation Flux Switching Machine with Segmental Rotor and Non-overlap Winding

Recently, a three-phase Field Excitation Flux Switching Motor (FEFSM) with salient rotor structure has been introduced with their advantages of easy rotor temperature elimination and controllable FEC magnetic flux particularly meet for high torque, high power as well as high speed diverse performances. Nevertheless, the salient rotor structure is found to lead a longer magnetic flux path between stator and rotor producing weak flux linkage along with low torque performances. Therefore, a new structure of a single-phase FEFSM using segmental rotor with non-overlap windings is proposed. Segmental rotor and non-overlap windings are the clear advantages of these topologies as the copper losses gets reduce and rotor becomes less weight as well as more robust. Detailed analysis on winding arrangement test analysis, armature and FEC flux linkage, back-EMF and average torque characteristics have been performed by using 2D Finite Element Analysis (FEA) through JMAG version 15 software. The results show that the proposed motor with segmental rotor and non-overlap windings produce short flux path, high flux linkage and the highest torque capability achieved is 0.91 Nm.

Magnetic Flux Analysis of a New Field-Excitation Flux Switching Motor Using Segmental Rotor

Recently, a three-phase field-excitation flux switching motor (FEFSM) with salient rotor structure has been introduced with their advantages of easy rotor temperature removal and controllable field excitation coil (FEC) magnetic flux particularly suitable for high torque, high power, and high-speed diverse performances. Nevertheless, the salient rotor structure is found to lead a longer magnetic flux path between stator and rotor producing weak flux linkage along with low torque performances. Besides, the overlap armature coil and FEC windings yield high coil end length, producing much high copper loss and large motor size. In this paper, a new FEFSM using segmental rotor with non-overlap armature coil and FEC windings is proposed. The shorter magnetic flux path of the proposed segmental rotor is noticeably more focused to produce much higher torque while the non-overlap armature and FEC will reduce the copper loss and motor weight. Both FEFSMs with salient and segmental rotors are designed using 2-D-FEA JMAG Designer version 14.1 for comparison. As a result, magnetic flux of the segmental rotor design is 11 times higher than the salient rotor structure mainly due to shorter magnetic flux linkage between two stator teeth and single rotor segment. The torque and power of 0.91 Nm and 293 W, respectively, are obtained from the new FEFSM which are much higher than salient rotor design. In addition, the simulation and experimental results show a good agreement in back-electromotive force amplitude and waveform at various speeds, as well as similar increment of torque versus FEC current characteristics. As the conclusion, the proposed FEFSM with non-overlap and segmental rotor structure has produced much higher flux, with significant improvement of torque and power performances compared with existing FEFSM with salient rotor.

Design Improvement of Three Phase 12Slot-14Pole Outer Rotor Field Excitation Flux Switching Motor

This paper present with design improvement of 12Slot-14Pole outer rotor field excitation flux switching motor (ORFEFSM) from the initial design by implement Deterministic Optimization Method (DOM) which involve 2-dimensional Finite-Element Analysis (FEA). The design improvement starts with the non-active part, rotor and followed with active part, stator which involve the armature coil slot and field excitation coil (FEC) slot. Since it is one of local optimization method, this method involves more than one cycle of improvement depends on the design structure and slot-pole configuration until achieve optimum performance. However, the initial torque and power output of 12Slot-14Pole is 112.95 Nm and 50.46 kW. The main objective is to improve the structure in order to obtain optimum torque and power output. Besides, it is necessary to reduce flux saturation and optimize the flux flow between the rotor teeth and stator arc width. The target torque and power output performance is expected higher than 210 Nm and 123 kW. With the deterministic optimization method technique, the final torque and power output achived are 221.83 Nm and 189kW.

Design Studies and Analysis of Single Phase 8S-12P Field Excitation Flux Switching Motor

This paper presents a new structure of field excitation flux switching motor (FEFSM) as an alternative candidate of non-permanent magnet (PM) machine. The rotor is consisted of only stack of iron and hence, it is reliable and appropriate for high speed operation. Initially, the coil arrangement tests are examined to validate the operating principle of the motor and to identify the zero rotor position. Furthermore, the profile of flux linkage, induced voltage, cogging torque, torque and power characteristics are observed based on 2D finite element analysis (FEA). Initial performances show that 8S-12P FEFSM produce torque and power of 8.79Nm and 1.5kW, respectively with low cogging torque and sinusoidal flux waveform. Further design refinement and optimization will be conducted to improve the performances of the motor.