In the conventional DTC, the selected voltage vector is applied for the whole switching period regardless of the magnitude of the torque error. This can result in high torque ripple. A better drive performance can be achieved by varying the duty ratio of the selected voltage vector during each switching period according to the magnitude of the torque error and position of the stator flux. A dut...

In this paper, four-switch inverter fed direct torque control three phase Induction Motor drive is presented. A triangular wave is used as dither signal of minute amplitude (for torque hysteresis band and flux hysteresis band respectively) in the error block. This method minimizes flux and torque ripple in a Four-Switch inverter fed induction motor drive while the dynamic performance is not aff...

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...

The conventional direct torque control (CDTC) is known to produce quick and robust response in induction motor drives. However, during steady state, torque, flux and current occur, which results in acoustical noise and incorrect speed estimations. The main objective of this paper is to present different hybrid space vector PWM (HSVPWM) methods for direct torque controlled induction motor for re...

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...

A new method for optimum shape design of variable capacitance micromotor VCM using Differential Evolution DE , a stochastic search algorithm, is presented. In this optimization exercise, the objective function aims to maximize torque value and minimize the torque ripple, where the geometric parameters are considered to be the variables. The optimization process is carried out using a combinatio...

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...

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...

This paper investigates the problem of the position control in switched reluctance motor drives. Advanced proportional-integral (PI) and proportional-differential (PD) controllers for the speed and position control, respectively, are adopted. The parameters of the controllers are on-line fine tuned according to the load torque and rotor speed, for providing high dynamic performance and precise ...