Baoquan Kou

Electrothermal Combined Optimization on Notch in Air-Cooled High-Speed Permanent-Magnet Generator

A 30 kVA, 96000 r/min, air-cooled high-speed permanent-magnet generator (HSPMG) is investigated in this paper. Considering effects on both the magnetic circuit and heat transfer paths comprehensively, the stator slot notch in this HSPMG is optimized. First, using the time-stepping finite-element method, the transient electromagnetic fields of HSPMG are numerically calculated, and the electromagnetic losses in different components are obtained. Then, after the determination of other mechanical losses in such a machine, a 3-D fluid-thermal coupling calculation model is established, and the working temperature distribution in the HSPMG is studied. Thus, the electromagnetic-fluid-thermal coupling analysis method on the HSPMG is proposed, and the use of the influences of machine notch height on machine magnetic circuit and cooling air flowing path are investigated. Meanwhile, both the electromagnetic performance and the temperature distribution in HSPMG with different stator notch height are studied, and a series of analytical equations is deduced to describe the variations of machine performances with stator notch. Using the proposed unbalance relative weighting method, the notch height is optimized to enhance the performance of HSPMG. The obtained conclusion could provide reference for HSPMG electromagnetic calculation, cooling system design, and optimization design.

Bidirectional Cross-Linking Transverse Flux Permanent Magnet Synchronous Motor

In this paper, a bidirectional cross-linking transverse flux permanent magnet synchronous motor is presented, which has a larger space utilization ratio than the traditional transverse flux machine. The stator core unit can make full use of rotor permanent magnets, and effectively increases no-load back-electromotive force (back-EMF), with the features of easy manufacturing. The structure and the driving principle of this motor are introduced. The 3-D magnetic circuit model is established, and the analytical expression of the no-load back-EMF and the torque are derived. In addition, the magnetic field and torque are analyzed by the 3-D finite element method (FEM). A prototype was designed and manufactured. The back-EMF and static torque experiments were carried out. The theoretical analyses agreed with the experimental results well. That verified the validity of the theoretical analysis.

Analysis and Design of a Novel 3-DOF Lorentz-Force-Driven DC Planar Motor

In this paper, a novel Lorentz-force-driven DC planar motor with low force ripple is proposed. The magnetic field distribution is calculated analytically by using magnetic surface charge model and image method. The expressions of force and torque are derived based on the Lorentz force law. A method for electromagnetic design of the motor is also discussed. The static force characteristic is measured experimentally. The experiment results are in good agreement with the results of the analysis and simulation.

Modeling and Design of an Integrated Winding Synchronous Permanent Magnet Planar Motor

This paper presents a novel integrated winding synchronous permanent magnet planar motor(IWSPMPM), which is driven by composite currents. In this research, the flux density distribution of a two-dimensional magnet array used for the IWSPMPM was obtained by solving the scalar magnetic potential. Expressions of the electromagnetic forces and back-EMF of the IWSPMPM were derived. Based on this, the main dimension of the IWSPMPM was confirmed, also the expression was derived. The design of the coil and permanent magnet was studied respectively, effects of the height of the coil and the thickness of the magnet on the electrical properties of the planar motor were analyzed. A prototype motor is manufactured, and some experiments were carried out with it. Both measurement and simulation coincide well.

Design and analysis of ironless linear electromagnetic launcher with high thrust density for space platform

As further research on space exploration and space platform technology, space-based electromagnetic launchers (EML) have aroused widespread attention and interest. This paper presents analysis and optimization of ironless permanent magnet linear synchronous motor (ILPMLSM) which easily meet requirements such as fast response, light weight, small volume and high precision positioning for space-based EML. Electromotive thrust and thrust per volume of ILPMLSM with non-overlapping and overlapping air-cored windings are compared based on the analysis of the magnetic field. It is shown that the overlapping winding machine has certain important advantages compared to the non-overlapping winding machine for space platform. Further, we propose a design optimization to improve thrust density and thrust ripple simultaneously by optimizing structure and dimensions of magnets and windings.The design optimization is verified by 2-D Finite Element analysis.

Characteristic Analysis of a Long-Stroke Synchronous Permanent Magnet Planar Motor

This paper deals with the characteristic analysis of a long-stroke synchronous permanent magnet planar motor. The planar motor which employs a 2-D permanent magnet array for the stator, is suitable for the long-stroke applications since the moving coils can move freely. Operation principle and structure of this planar motor are introduced. Characteristics such as flux density, thrust and back-EMF are obtained analytically and compared with the finite element simulation results. A prototype motor is manufactured and successfully tested. The measured values are also in good agreement with the simulation ones.

Research on loss of high speed permanent magnet synchronous motor for flywheel energy storage

As advantages of high energy density and large instantaneous power, flywheel energy storage is very promising energy storage technology in recent years. High-speed permanent magnet synchronous motor (HSPMSM) with low loss and high efficiency is one of the crucial components of flywheel energy storage (FES), and Loss calculation is crucial to designing high-speed PMSM. In this paper, a 30 kW, 96000 rpm HSPMSM is designed and analyzed. The copper loss, iron loss, rotor eddy current loss, mechanical loss, wind driven loss are detailedly analyzed and calculated.

Modeling and analysis of a maglev vibration isolation unit using rectangle Halbach permanent magnet array

A maglev vibration isolation unit (MVIU) using rectangle Halbach permanent magnet array used for ultra-precision equipment and instruments vibration isolation is proposed in this paper. The structure and operation principle of this maglev vibration isolation unit are introduced. Analytical solutions to determine the field of the maglev vibration isolation unit are deduced. The correctness of the solutions is validated by comparison of the results obtained by analytic method and by finite element method. Based on the analytic solutions, the magnetic force and natural frequency of the maglev vibration isolation unit is also deduced in this paper.

Research on electromagnetic force of a large thrust force permanent magnet synchronous linear motor

An 18 slot and 21 pole large thrust force permanent magnet synchronous linear motor (PMSLM) is designed. We research on the thrust force and normal force from the aspects of thickness of yoke of primary core and secondary core, thickness and width of permanent magnet, air gap length, the width of slot and turns of coils. The optimized design of maximum thrust force is completed. The test result is corresponding to the analysis which verifies the large thrust force PMSLM takes the advantages of large thrust force, small ripple and high precision and has a good prospect of applications in electromagnetic launch and numerical control machine.

Research on a permanent magnet synchronous motor with parted permanent magnet used for spindle

A wide flux weakening speed range permanent magnet synchronous motor with parted permanent magnet used for spindle was presented. The torque and flux weakening performance of three motors with different permanent magnet in rotor are compared. The rotor shape is optimized to reduce third harmonic wave and ripple of no-load torque. We research on the torque and flux weakening characteristics of the PMSM with parted permanent magnet. The analysis and emulation verify the validity and feasibility of flux wakening for the motor.