Antonios Kladas

Evolutionary optimization of Permanent Magnet machine design for traction applications

Permanent Magnet (PM) machines constitute a favored drive choice in electric traction applications due to their increased efficiency. Design optimization of such machines could enhance their ability to satisfy contradictory static and dynamic requirements. In this paper a Differential Evolution (DE) algorithm for PM machine design optimization, coupled with a finite element analysis (FEA) is employed.

Wind Turbine Control Strategy Enabling Mechanical Stress Reduction Based on Dynamic Model Including Blade Oscillation Effects

The paper presents a coupled electrical aerodynamic model for a three blade wind-turbine dynamic analysis. The model is based on a blade element representation of the aerodynamic load part combined with an aeroelastic beam element for the dynamic analysis of a real rotor blade, including top tower acceleration. The model involves reduced computation time enabling to be applied in control system hardware. Such an analysis is very promising for obtaining controllers involving compromises among contradictory targets such as energy capture maximization and mechanical stresses reduction in the aerodynamic part.

Numerical Simulation of MgB2 Superconducting Magnetic Energy Storage Coil

A coupled thermal electromagnetic finite element analysis has been used to numerically simulate the electromagnetic characteristics of an MgB2 SMES coil. Magnetic field distribution data and current density predictions of the numerical model were compared with the literature and with the superconducting properties of explosively consolidated MgB2 samples measured experimentally. The material Jc characteristics were determined by applying Bean’s critical state model on the material magnetisation measurements conducted on a superconducting quantum interference device (SQUID).

Dynamic finite element hysteresis model for iron loss calculation under PWM excitation

The paper introduces a dynamic finite element model for calculating iron loss in ferromagnetic laminations under PWM excitation. The proposed methodology accounts for static hysteresis, classical eddy currents and anomalous losses and has been applied to predict hysteresis loops in Epstein device in three different cases of PWM voltage waveform types: unipolar, bipolar and square wave. The model is tuned by using standard static iron lamination characteristics provided by constructors and offers sufficient accuracy in all the aforementioned cases.

Electromagnetic Compatibility Issues in Electric Vehicle Applications

The paper develops analyses electromagnetic compatibility issues in electric vehicles. Particular techniques are developed involving special elements of tubular geometry based on the analytical solution of diffusion equation combined with standard finite elements, for analysis of electromagnetic shielding effectiveness in power cables due to power static converter operation. Particular simulations analyze the exposure levels due to variable frequency magnetic field on anatomically detailed human models in electric vehicle cabin environment. The results obtained have been compared to those found in the literature and to measured ones.

Particular electromagnetic shielding analysis of cables for electric vehicle applications

The paper develops a special element of tubular geometry based on the analytical solution of diffusion equation combined with standard finite elements, for analysis of electromagnetic shielding effectiveness in power cables due to power static converter operation. Particular simulations analyze the exposure levels due to variable frequency magnetic field on anatomically detailed human models in electric vehicle cabin environment. The results obtained have been compared to those found in the literature and to measured ones.

Model Predictive Control Employing Finite-Element Methods for Aerospace Actuators

In this paper the strategy of the extraction of an advanced simulation model of interior permanent magnet synchronous machine is suggested in order to be employed by Model Predictive Control schemes. The conventional dq-axis mathematical model is modified in order to include data derived from finite element analysis (FEA). Indirect interaction between FEA and circuit simulation enhances model fidelity embodying the influence of saturation and cross-coupling effects. The proposed method of developing a detailed simulation model opens new prospects on the control of electrical machines.

Parameter Extraction of a PM Machine Employing 3D Finite Element Analysis Tools for Model Predictive Control Schemes

This paper introduces a permanent magnet (PM) machine model accounting for saturation effects and non-sinusoidal electromotive force (EMF) employed in model predictive control schemes. The procedure of the model parameters determination is based on the three dimensional finite element analysis (FEA) considering saturation and cross-coupling effects. The conventional equivalent circuit model is subject to modifications so as to incorporate data derived from FEA enabling the model predictive control strategies to obtain proper actions for the converter operation based on the accurate prediction of the machine performance. The regeneration of the n-order harmonic components of the non-sinusoidal EMF is attained by combining methods of superposition and approximation estimating the output voltage at the machine terminals for different loading and speed. Developed model simulation results have been validated by experiments performed on an inset PM machine prototype.

Evolutionary Optimization of a Fractional Slot Interior Permanent Magnet Motor for a Small Electric Bus

Fractional Slot Concentrated Winding (FSCW) Interior Permanent Magnet (IPM) motors constitute a favorable choice for electric vehicle applications due to their inherent advantages of high efficiency and performance, field weakening capability and permanent magnet effective shielding from eddy currents. In this paper, an IPM motor with buried sinusoidal magnets for a small electric bus is optimized in terms of both efficiency and performance. The overall magnet volume and the corresponding iron bridge width are maintained within specified borders, thus enabling adequate field weakening and permanent magnet shielding margins. In the optimization process a single-objective Differential Evolution (DE) algorithm is utilized, showing great convergence characteristics.

Design Considerations for an In-Wheel PM Motor with Fractional Slot Concentrated Windings for Light Electric Vehicle Applications

Design optimization of traction motors for light electric vehicles requires a comparative analysis in order to account for both performance and efficiency, while considering overall cost, size limitations and manufacturing complexity. This paper presents a comparative study on different surface mounted permanent magnet (SMPM) in-wheel motor configurations, facilitating fractional slot concentrated windings (FSCW). On a first step, different pole/ slot combinations were investigated and evaluated in terms of performance primarily. On a second step, different stator geometries were analyzed, considering both double and single layer windings and both equal and unequal stator teeth. Two different operating conditions were taken into account, i.e. nominal load and overload. The most advantageous was selected, by means of efficiency, clean interface and overall weight, using an extensive sensitivity analysis. On a third step, the final geometry was optimized, via fine-tuning of key design variables, accounting for maximum efficiency and minimum machine weight.