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A MATLAB environment based mathematical model of a 4- phase Switched Reluctance Machine (SRM) with fewer experimental flux linkage and static torque data, with possible measurements using instruments within accuracy and precision, and more extended data with interpolation respectively is presented. The main objective of this research is to investigate the performance of SRM with variable available data used as lookup data in the model of SRM. Firstly, the necessary experimental input data is discussed. Then, these data points are extended for a range of current and rotor positions. Finally, simulations are carried out under these data for the same operating conditions. The accuracy of the results is verified by comparing the simulated current and torque profile of the machine with an experimental current profile. [ABSTRACT FROM AUTHOR]

Switched reluctance machine (SRM) has progressed as a suitable contender in the family of electrical machines for its high starting torque and better performance in different operating conditions. The need for accurate modeling of this machine is, therefore, dependent on the accurate determination of losses of which iron loss is exigent. This article aims to determine iron loss from the equivalent circuit parameters of the machine based on the input data tables that are directly obtained from the experiments carried out on an existing four-phase, bifilar wound SRM. The procedure and necessary steps for the loss separation method are well defined and supported by the theoretical and practical results. The experimental determination of the iron losses has been compared with the predicted results under the same operating conditions. [ABSTRACT FROM AUTHOR]

This paper proposes a novel brushless excitation topology for a three-phase synchronous machine based on a customary current-controlled voltage source inverter (VSI). The inverter employs a simple hysteresis-controller-based current control scheme that enables it to inject a three-phase armature current to the stator winding which contains a dc offset. This dc offset generates an additional air gap magneto-motive force (MMF). On the rotor side, an additional harmonic winding is mounted to harness the harmonic power from the air gap flux. Since a third harmonic flux is generated in this type of topology, the machine structure is also modified to accommodate the third harmonic rotor winding to have a voltage induced as the rotor rotates at synchronous speed. Specifically, four-pole armature and field winding patterns are used, whereas the harmonic winding is configured for a twelve-pole pattern. A diode rectifier is also mounted on the rotor between the harmonic and field windings. Therefore, the generated voltage on the harmonic winding feeds the current to the field winding for excitation. A 2D-finite element analysis (FEA) in JMAG-Designer was carried out for performance evaluation and verification of the topology. The simulation results are consistent with the proposed theory. The topology could reduce the cost and stator winding volume compared to a conventional brushless machine, with good potential for various applications. [ABSTRACT FROM AUTHOR]

This paper presents a proposed model of a multi-stack slotted stator axial-flux type permanent magnet synchronous machine (AFPMSM) specifically for reducing torque ripple. The proposed AFPMSM model uses pentagon-shaped permanent magnets (PMs). It has a low value of cogging torque and torque ripples compared to the conventional model with a trapezoidal magnet shape. Additionally, it has increased internal generated voltage (Ef) as compared to the conventional model. To further enhance Ef phases and minimize cogging torque of the proposed model, the proposed AFPMSM model was optimized by varying different sides of PMs using a genetic algorithm (GA). A time-stepped three-dimensional (3D) finite element analysis (FEA) was performed for the comparative analysis of conventional, proposed, and optimized AFPMSM models. From this comparative performance analysis, it is observed that torque ripples and cogging torque of the optimized AFPMSM are significantly decreased, while output average torque is appreciably increased. Ef and output power are also enhanced. [ABSTRACT FROM AUTHOR]