Induction machine drive based on Direct Torque Control (DTC) allows high dynamic performance with very simple hysteresis control scheme. Conventional Direct Torque Control (CDTC) suffers from some drawbacks such as high torque ripple and variable switching frequency , difficulties in torque as well as flux control at very low speed. This paper is aimed to analyze DTC principles, the strategies ...

Hybrid stepper motors (HSMs) are commonly used in many cost-sensitive industrial and consumer applications. With the use of micro-stepping techniques, they could theoretically achieve a very high resolution in positioning of mechanical loads, even without position sensors. However, it is well known that HSMs are affected by a large torque ripple, due to cogging and phase unbalancing. This, in t...

Abstract-Voltage sag or unbalance conditions at the input rectifier stage of the ac-dc-ac rectifier-inverter induction motor drive can cause the significant amounts of harmonic voltage at twice the line frequency 2f1. This voltage ripple can have a degrading effect on the induction-machine performance characteristics. This paper presents an analytical closed-form mathematical model and analysis...

This paper uses the flux-MMF diagram to compare and contrast the torque production mechanism in seven common types of electric motor. The flux-mmf diagram is a generaked version of the flux-linkage versus current (+i) diagram €or switched-reluctance motors. It is illustrated €or switchedreluctance, synchronous-reluctance, induction, brushless ac, brushless dc, interior PM and dc commutator moto...

recently, transverse flux permanent magnet generators (tfpmgs) have been proposed as a possible generator in direct drive variable speed wind turbines due to their unique merits. generally, the quality of output power in these systems is lower than multi stage fixed speed systems, because of removing the gears, so it’s important to design these kinds of generators with low ripple and lowest har...

This paper presents some techniques for driving novel 5 phase dual winding PMSM (Permanent Magnet Synchronous Motor) the in-wheel motor. The motor realizes change over characteristics that can expand area from high-torque mode to high-speed due construction. However, structure makes a high-current ripple high coupling between windings. proposes control methods reduce current ripple, including i...

Brushless DC motor has a rotor with permanent magnet and has no mechanical commutator which leads to many advantages like less maintenance, long life, high reliability, low inertia, low friction and low noise. Since the brush system/commutator assembly is replaced by an electronic controller which can be easily integrated into other required electronics, thereby improving the effective power to...

This paper presents a modeling and analysis of multi-phase inverter fed multi-phase induction motor drive with different number of phases. Multiphase induction motor drives possess several advantages over conventional three-phase drives such as lower torque pulsation, fault tolerance, stability, high efficiency and lower current ripple and reduced current per phase without increasing voltage pe...

Permanent magnet synchronous machines generate parasitic torque pulsations owing to distortion of the stator flux linkage distribution, variable magnetic reluctance at the stator slots, and secondary phenomena. The consequences are speed oscillations which, although small in magnitude, deteriorate the performance of the drive in demanding applications. The parasitic effects are analysed and mod...

In this paper a multiobjective optimal design method of interior permanent magnet synchronous motor ( IPMSM) for traction applications so as to maximize average torque and to minimize torque ripple has been presented. Based on train motion equations and physical properties of train, desired specifications such as steady state speed, rated output power, acceleration time and rated speed of tract...