Krzysztof Kowalski

The 3D coupled field-circuit simulation of transients in nonlinear systems

An algorithm for simultaneously solving the equations describing the 3D magnetic field and equations describing electric circuits of electromagnetic devices has been elaborated. The nonlinearity and anisotropy of the magnetic core have been taken into account. In order to solve the 3D problem a special iterative procedure, in which the 3D task is substituted with a sequence of 2D problems, has been proposed. For the sake of example, the calculations for an a.c. actuator have been made.

Decomposition of the compromise objective function in the permanent magnet synchronous motor optimization

Purpose – The purpose of this paper is to elaborate an algorithm and the computer code for the optimization of the permanent magnet synchronous motor (PMSM) including the shaft torque, the cogging torque, the total harmonic distortion factor of the back EMF and magnet volume into compromise objective function. Design/methodology/approach – The mathematical model of the device includes the magnetic field equations with the nonlinearity of the magnetic core taken into account. The numerical implementation is based on the finite element method (FEM) and time stepping procedure. The genetic algorithm has been applied for the optimization. The comprehensive computer code containing the FEM model and optimization procedures have been elaborated. Findings – Very important problem at formulating the optimization task is the choice of the functional parameters which constitute the objective and constraint functions. In the paper it has been shown that uncritical constructing the objective function could lead to ir...

Optimization of an Electromagnetic Linear Actuator Operating in Error Actuated Control System

In the paper an algorithm and computer software for the optimisation of error actuated control systems containing of an electromagnetic linear actuator is presented. The software consists of two main parts: (a) optimisation solver and (b) numerical model of the actuator. For the optimisation, the genetic algorithm (GA) has been used. The field discrete mathematical description is employed. The field-circuit model of the electromagnetic actuator includes: (a) the equation of a transient electromagnetic field, (b) equations which describe electric circuits of the system, including feedback, (c) the equation of mechanical motion and (d) the equation describing and the proportional-plus-integral-plus-derivative (PID) controller.

Optimization of magnetostrictive actuator taking dynamic parameters into account

In the paper an algorithm and software fors optimization of the magnetostrictive actuator, taking the dynamic parameters into account is presented. The device is applied as a drive for plasma valve and is characterised by very short time of operation. The structure with cylindrical core and cylindrical exciting winding supplied with discharging capacitor current pulses is designed. The field-circuit mathematical model of the dynamic operation of the actuator has been applied. Two optimization strategies are proposed. In the first strategy the compromise objective function is constructed; in the second one — the penalty function is included into the objective function.

Influence of eddy currents on the dynamics of the magnetostrictive actuator for plasma gun valve drive

In the paper, the influence of eddy current induced in the magnetostrictive core on the dynamics of fast-acting actuator applied as a driving device for valve of plasma gun is considered. The field-circuit mathematical model of the dynamic operation of the system capacitor-actuator has been applied. Two kinds of the core non-linearity have been taken into account. It has been proved that eddy currents have an essential effect on the actuator dynamics.