The paper deals with the problem of position and speed estimation methods in SRM (Switched Reluctance Motor) drive equipped with hysteresis band current controller with MRAS (Model Reference Adaptive System) type observer. An adaptive flux model uses equation set of one-dimensional equations instead of one two-dimensional equation. The reference model is the formal one. Instead of measured current the observer utilizes reference current. Such drive system works well at speed range up to 600 rad/s. The observer's gains must change depend on the speed range. The robustness on motor parameter poor estimation is presented.
An approach helpful when developing an optimized construction of a 6/4 type switched reluctance motor (SRM) is described in the paper. The analytical modeling procedure, based on the reluctance network method and analytical solution of an ordinary differential equation, enables applying a gradient optimization routine and better control of optimization process. The model allows for estimation of the efficiency, torque, and acoustic noise of the motor taking into account the magnetic non-linearity and the control algorithm to keep a constant input power. A bicriterial optimization routine has been applied to find optimal constructions. Eleven geometric and winding parameters are supposed to be the optimization quantities. Analyzed constructions – the initial one and the optimized ones, were validated by means of FEM calculations. The proposed approach can be employed in designing the SRM to be a drive motor in an electrical vehicle, at least as a first attempt.
Switched reluctance motors (SRMs) are still under development to maximise their already proven usefulness.Amagnetic circuit of theSRMcan be made of soft magnetic composites (SMCs). The SMCs are composed of iron powder with dielectric and have a lot of advantages in comparison to commonly used electrical steel. The paper deals with the modelling and analysis of theSRMproduced by Emerson Electric Co. forwashing machines. Numerical calculations and modelling were done using the FEMM 4.2 program. Magnetic flux densities and magnetic flux lines were calculated, as well as electromagnetic torque and inductance for changing the position of a stator to a rotor. The obtained results were compared with other measurement results and are quite similar. The developed numerical model will be used for the project of a motor with an SMC magnetic circuit.
In the paper, the modified (compared to the classical asymmetric half-bridge) converter for a switched reluctance machine with an asymmetric rotor magnetic circuit was analysed. An analysis for two various structures of switched reluctance motors was conducted. The rotor shaping was used to obtain required start-up torque or/and to obtain less electromagnetic torque ripple. The discussed converter gives a possibility to turn a phase off much later while reduced time of a current flows in a negative slope of inductance. The results of the research in the form of waveforms of currents, voltages and electromagnetic torque were presented. Conclusions were formulated concerning the comparison of the characteristics of SRM supplied by the classic converter and by the one supplied by the analysed converter.
This paper presents optimization results for a two-phase, modular transverse flux switched reluctance motor (TFSRM) with an outer rotor. In particular, the main disadvantage of the considered motor structure, that is the zero starting torque in some rotor positions, is eliminated by construction optimization. A numerical model of the motor developed in the Flux3D program is coupled with a Matlab-based evolutionary algorithm for optimization of construction parameters of the magnetic circuit. The elaboratem algorithm is also connected with a database to limit the computation costs. Three objective functions are taken into account for the motor integral parameter improvement. The fundamental role of a type of an optimization criterion function is comparatively analyzed and a new effective criterion function is introduced.