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Purpose - The purpose of this paper is to include thermal analysis in the design process of permanent magnet synchronous motor (PMSM). The additional objective is a comparison of PMSM with induction motor (IM) in terms of thermal phenomena. Design/methodology/approach - Numerical investigation using commercial software MotorSolve was performed. Parameterized models of PMSM and IM were used. Calculations of motor parameters and temperature distribution were made using Finite Element Method. Findings - The results of the calculations show that thermal calculations should be included in the design process because the maximum permissible operating temperature of permanent magnets should not be exceeded. A comparative analysis of PMSM and IM shows that the PMSM has better parameters than the IM which was used as a base of the PMSM construction. Research limitations/implications - Computational models should be verified experimentally on a physical model or by using more complex numerical models. In the case of IM thermal calculations, a method of air speed calculation should be proposed. Air speed is a parameter that is necessary in thermal analysis of IM, but during the design process it is unknown. Originality/value - This paper presents modelling methodology of 3D transient thermal field coupled with electromagnetic field applied in a three-phase IM at rated load conditions. This paper presents a design strategy which includes thermal analysis of the designed PMSM. Moreover, the paper shows a comparison between PMSM and IM indicating advantages of PMSM over IM. [ABSTRACT FROM AUTHOR]

Purpose - The purpose of this paper is to present a comparative study of the thermal behavior and efficiency of an induction motor fed by a fault-tolerant Three-Level Neutral Point Clamped (3LNPC) inverter, under normal conditions as well as after a post-fault reconfiguration, following an open-circuit fault in the inverter. For this purpose, a Matlab/Simulink model and three-phase induction motor models using a finite element method (FEM) software were developed. Besides, some experimental tests were conducted for different values of the induction motor load torque and speed reference to validate the models. Design/methodology/approach - To assess the thermal behavior and efficiency of the motor, electromagnetic and thermal models using a FEM software were developed. The coupling with the inverter drive is accomplished through a developed model in Matlab/Simulink which also includes the control system. The simulation tests were performed for a healthy and faulty inverter at different operating points of the three-phase induction motor. To validate the FEM models some experimental tests were performed. Findings - When the inverter operates in reconfigured mode the motor losses are higher and consequently temperature is higher and the motor efficiency is lower. The developed models are an alternative to a more detailed study of the motor when fed by a 3LNPC inverter and consequent optimization of the control system. Originality/value - With the developed tools, a better understanding of the motor behavior and performance is gained, allowing to forecast scenarios and optimize fault-tolerant control strategies for the drive. [ABSTRACT FROM AUTHOR]

Purpose - The purpose of this paper is to present the distribution of the magnetic field and additional losses analysis of the induction motors (IM) with opened and closed rotor slots. Design/methodology/approach - In the field-circuit approach the distribution and changes of magnetic flux density in the motor are computed using a time-stepping finite element method. The additional losses in each element are evaluated at different frequencies. Findings - An approximate analytical formulation is derived for rapid losses computation confirmed by the results of field-circuit method. For high-voltage motors due to the size ratios of the core and relatively deep stator and rotor slots major role in causing loss of higher harmonics play a fundamental slot harmonics. Higher harmonics order bigger than 100 cause only small part of total higher harmonics core losses. Closed rotor slots construction influenced significantly on no-load losses mainly due to reduction of losses at slot upper part. For nominal load condition that influence is not so strong according to the saturation of slot tips by rotor leakage flux. Nevertheless, core losses at load are several times higher as at no-load. Research limitations/implications - In future research authors will take into account motors feed from PWM inverter, working in the frequency range up to 400 Hz. Practical implications - The results of investigation will be used in more detailed design of IMs especially for motors with closed rotor slots. Originality/value - The methods presented in the paper was not used before. Also results of additional losses in the motor core calculation, especially according motors with closed slots at no load and load conditions are new. [ABSTRACT FROM AUTHOR]