Microwave absorbing properties of ferrites and their composites: A review

High-speed permanent-magnet synchronous machines (HS PMSMs) are a popular topology among modern electrical machines. Suitable applications for such machines are low-power vacuum pumps, compressors, and chillers. This paper describes a systematic design methodology for an HS PMSM using two case studies. The design process for such high-speed (HS) machines is multidisciplinary and highly iterative due to the complex interaction of the many design variables involved. Consequently, no single optimum solution exists, and multiple possible solutions can meet the customer requirements. Practical solutions should be within acceptable thermal limits, should be energy-efficient, and should be rigid enough to withstand the forces exerted during operation. The proposed design flow is divided into steps that are presented in this paper in the form of a flowchart with emphasis on mechanical aspects. Each step represents a task for a thermal, mechanical, or electrical engineer. The features of each step and the prerequisites for moving to the next step are discussed. The described methodology was implemented in the design of two HS PMSMs. The output performance results of the design flow are compared with measured results of the prototypes. The design process described in this paper provides a straightforward procedure for the multidisciplinary design of HS permanent magnet electrical machines.

Multidisciplinary Design Process of a 6-Slot 2-Pole High-Speed Permanent-Magnet Synchronous Machine

Analytical models play an important role in the design of electromagnetic devices by providing computationally efficient solutions. In this paper, by combining magnetic equivalent circuit approaches and Faraday's and Ampere's laws, a model for radial-flux eddy-current couplers is developed, which can easily handle complex geometries as well as account for iron saturation, all material properties, and three-dimensional (3-D) parameters. The characteristics and the design considerations of a surface-mounted permanent-magnet structure are presented. Also, a procedure aimed at an optimal design of the yoke thicknesses is utilized. Moreover, 2-D and 3-D finite-element methods are employed in the analyses and evaluation of the model. Finally, sensitivity analysis is performed to explore the impacts of the machine parameters on the device performance.

Nonlinear Modeling of Eddy-Current Couplers

In this paper, the design optimization of a nonsalient high-speed permanent magnet synchronous machine (PMSM) for electric vehicle applications is presented. It will be shown how, with a new approach, it is possible to find a deterministic solution to solve the sizing of the machine from a given driving cycle. The optimal geometry and the optimal control strategy over the cycle minimizing both the energy losses and the volume of the machine will be calculated. At first, the one-dimensional analytical model used is presented and validated for the most significant point of the driving cycle using a finite element method. Then, the design methodology and the results through a specific application are detailed. Particularly, it will be shown how the flux weakening, directly given by the design process via the optimization of the control strategy, allows reducing both the energy losses and the constraints on the power converter. At last, in order to validate the solution considering the whole cycle while keeping a reduced computation time, a reluctance network model of the PMSM is used. This model validate the energy losses and the flux densities in the steel parts over the cycle. The study will be done considering the urban dynamometer driving schedule.

Design Optimization with Flux Weakening of High-Speed PMSM for Electrical Vehicle Considering the Driving Cycle

A directly coupled magneto-mechanical model is proposed for simulating the effect of the magnetostriction and electromagnetic stress in iron. The model is based on the general balance laws of electromagnetism, mechanics, and continuum thermodynamics. It is implemented in 2-D by using a conforming finite element method for the magnetic vector potential and the displacement field. The method is applied to two different types of induction machines.

FEM for directly coupled magneto-mechanical phenomena in electrical machinesKatarzyna

Effect of simultaneous plastic and elastic deformation on magnetic properties of electrical steel sheets

This paper presents the application of the particle swarm algorithm for optimization of the stator slot-geometry of a high-speed permanent magnet synchronous machine.

Particle swarm optimization of the stator of a high speed PM synchronous machine

In this work, we study how the deterioration caused by electrical steel sheet cutting can be implemented in finite-element simulation of electrical machines in an effective manner. We use exponential decay as the degradation profile and propose a new method for the numerical integration using Gauss-Jacobi quadratures. The method is tested for 1-D case, and highly accurate results are obtained.

Effective Implementation of the Effect of Electrical Steel Sheet Cutting into Finite-Element Simulation

In this paper, a computationally effective iron loss calculation method for synchronous machines is presented. The method is based on a single static 2D finite element field solution in the machine cross-section, which makes it much faster than the one based on the time-stepping solution. The developed method is applied to a salient pole synchronous machine, and the computational accuracy is validated against the time-stepping method. The proposed iron losses computation method showed a fair accuracy and a considerable speed-up of the computations. It can be an excellent alternative for the iron losses estimation in the optimization procedure of synchronous machines, where a considerable amount of finite element solutions needs to be carried out. Besides the losses comparison, local reconstruction of the time dependency of other quantities such as the magnetic vector potential and the magnetic flux density is reported for a better understanding of the method.

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A Computationally Effective Method for Iron Loss Estimation in a Synchronous Machine from a Static Field Solution

This paper deals with current-regulated V/Hz control for induction motors. The analyzed control method incorporates an outer voltage control loop and an inner current control loop. Consequently, the stator current can be limited and unnecessary overcurrent trips avoided. Stability of the control system is analyzed by means of small-signal linearization. It is shown that the current-regulated V/Hz control has similar regions of instability as conventional V/Hz control. Static output feedback can be used to increase the stable operating region and improve system damping.

Floran Martin

Papers

Effect of simultaneous plastic and elastic deformation on magnetic properties of electrical steel sheets

Particle swarm optimization of the stator of a high speed PM synchronous machine

Effective Implementation of the Effect of Electrical Steel Sheet Cutting into Finite-Element Simulation

A Computationally Effective Method for Iron Loss Estimation in a Synchronous Machine from a Static Field Solution

Current-Regulated V/Hz Control of Induction Motors