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Various Rotor Topologies of Line-Start Synchronous Motor for Efficiency Improvement

Sarac Vasilija Jovan, Stefanov Goce

Power Electronics and Drives

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2020

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Vol. 5 (40)

83--95

EN

Line-start synchronous permanent magnet motor (LSSPMM) is being considered as a replacement or alternative to asynchronous squirrel-cage motor (AM) in constant speed applications. This is due to the better efficiency and power factor than the asynchronous motor. There are various rotor topologies of LSSPMM concerning the magnets placement and their dimensions. The paper analyses six different rotor topologies in terms of achieving the best efficiency and power factor for the same output power of the motor with minimal consumption of permanent magnet material. All other motor design parameters remain unchanged, i.e. all motor topologies are analysed for the same stator laminations and the same motor windings. The numerical finite element method (FEM) models and dynamic models for obtaining transient characteristics of speed, torque and current verify the proposed design of various motor models. The results from all motor models are compared and adequate conclusions are derived regarding the optimal rotor topology in terms of obtaining the best efficiency and power factor with minimal consumption of permanent magnet material, for the same output power of the motor.

2

Resonance mechanisms of a single line-to-ground fault on ungrounded systems

Jiang Jun, Liu Ling

Archives of Electrical Engineering

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2020

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Vol. 69, nr 2

455--466

EN

As for a single line-to-ground fault in an ungrounded distribution system, the power-frequency current is too low to detect the fault. The transient current is more palpable than that at a power-frequency of 50 or 60 Hz. It is an effective method to estimate the fault using the transient fault current. To analyze and calculate the transient current of single line-to-ground faults, an equivalent circuit is proposed in this paper. This model is based on distributed parameters of power lines. And it contains positive, negative and zero sequence information. The transient equivalent circuit consists of equivalent resistance, equivalent inductance and equivalent capacitance. And the method of calculation the equivalent elements is also submitted. MATLAB simulation results show that the new transient equivalent circuit has higher accuracy and stronger adaptability compared with the traditional one.

3

Dynamic Simulation of Fractional Horse Power Single-Phase Permanent Magnet Synchronous Motor

Petkovska L., Cvetkovski G.

Przegląd Elektrotechniczny

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2008

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R. 84, nr 12

217-220

EN

In the paper transient performance simulation procedures and the dynamic characteristics analysis, based on the magnetic field solution techniques is presented. The studied object is a small single-phase permanent magnet synchronous motor (SPPMSM). By using the Finite Element Method (FEM), extended numerical calculations of the SPPM synchronous motor magnetic field are carried out. The goal of the paper is to simulate dynamic characteristics in MATLABŽSimulink environment and to carry out the transient analysis of the motor.

PL

W artykule przedstawiono procedury symulacyjne stanu przejściowego oraz analizę charakterystyki dynamicznej bazujące na technikach analizy pola magnetycznego. Badany obiekt jest małym synchronicznym silnikiem jednofazowym z magnesami trwałymi. Wykorzystując MES przeprowadzono rozszerzone obliczenia numeryczne tego silnika. Celem tego artykułu jest symulacja charakterystyki dynamicznej w środowisku MatlabaŽSimulinka oraz przeprowadzenie analizy stanów przejściowych.