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Purpose - The purpose of this paper is to elaborate a method of computer analysis of high-speed motor with specific parameters and verifying the obtained results, i.e. computer models by experimental (laboratory) tests. Design/methodology/approach - In order to determine motor properties from the viewpoint of energy conversion, a model using FEM was worked out with the help of Maxwell software. To determine static and dynamic properties of both motor and drive, Matlab/Simulink models were used; one of these models was a built-in (library) model, the other one was proposed by the authors. Findings - The new analysis method and model of high-speed motor have been carried out. Research limitations/implications - The permanent magnet brushless direct current high-speed motor was the subject of the research. In the first part of the research, the properties of the motor were determined by using finite element method. Practical implications - The laboratory prototype can be a starting point in establishing the production of the high-speed motors with rotational speed in the range of 50,000-100,000?rpm. Social implications - At this moment, there are several possible application of the high-speed motor and it should be expected that other new applications can appear in near future after the start of the production. Originality/value - The paper shows that the computer-based analysis method determines the motor properties accurately. It is also pointed out that a motor with half-open slots has advantageous properties. The new simulation model of high-speed motor has been carried out. This model allows taking into account some imperfections caused by slots and rectangular cross-section magnets. [ABSTRACT FROM AUTHOR]

Purpose - In the electromagnetic field simulation of modern servo drives, the computation of higher time and space harmonics is essential to consider appearing torque pulsations, radial forces and ripple torques. The purpose of this paper is to propose a method to cover the effect of saturation on the armature flux density within conformal mapping (CM) by an finite element (FE) re-parameterization. Design/methodology/approach - Field computation by CM techniques is a time-effective method to compute the radial and tangential field components, but it generally neglects the effect of saturation. Findings - This paper presents a method to re-parameterize the CM approach by single FE computations so as to consider saturation in the model over a wide operation range of the electrical drive. Practical implications - The proposed method is applied to a surface permanent magnet synchronous machine, and compared to numerical results obtained by finite element analysis (FEA). Originality/value - The paper shows that an accuracy similar to that of FE simulations can be obtained with still the low-computation time that is the characteristic of analytical models. [ABSTRACT FROM AUTHOR]

Purpose - The purpose of this paper is to present the dependence of the level and harmonic structure of the cogging torque in permanent magnet synchronous motors (PMSM) to interlocks and notches in a stator back iron, which are standard methods for stator lamination stacking in mass-production. Design/methodology/approach - Methods of stacking up the lamination like welding or interlocking are introducing magnetic asymmetries in stator back iron which causes additional harmonic components (AHC). A finite element method and Fast Fourier transform were used to calculate cogging torque harmonic components (HC) with regard to the applied number and positions of interlocks and notches. All simulation results were verified by laboratory tests. Findings - It has been established and proved that technologies for stacking lamination packs cause local saturation peaks in back iron which give rise to additional cogging torque AHC and consequently increase the total cogging torque. It is also shown that the magnetic properties of interlocks cannot be simply considered as air regions but adequate relative permeability of such affected soft magnetic material must be determined to improve the accuracy of FEM calculations. Practical implications - Considering presented results, it is possible to foresee which AHC will include the cogging torque of mass-produced PMSMs due to the stator lamination stacking methods. In this way, the optimal stacking method can be selected in order to minimize the effect of AHC. Originality/value - So far, authors dealing with the cogging torque have not taken into account the influence of the stator lamination stacking method on the level of torque oscillations. [ABSTRACT FROM AUTHOR]