In this paper, the author proposes a sensorless direct torque control (DTC) of an induction motor (IM) fed by seven-level NPC inverter using artificial neural networks (ANN) and fuzzy logic controller. Fuzzy PI controller is used for controlling the rotor speed and ANN applied in switching select stator voltage. The control method proposed in this paper can reduce the torque, stator flux and to...

In this manuscript, the author has tried to analyze a study of Variable Frequency Drives. Variable frequency drives are energy saving drives. But they generate harmonics generates. Harmonics introduced by any means affect the performance parameters of any system The presence of harmonics is the system for a long duration & that, too, of higher order affect the various parameters in a Power dist...

One of the important factors influencing outdoor insulators performance is pollution phenomenon. The pollution, especially during humidity condition, reduces superficial resistance of insulator and lead to a flow of Leakage Currents (LC) on the insulator surface, which may result in total flashover. The LC characteristics are affected by parameters such as nature and severity of pollution. Loca...

This work proposes three phase five level Bridge module type Diode Clamped Multilevel Inverter (DCMLI) using various modulating techniques for induction motor load. These Pulse Width Modulating (PWM) techniques include Carrier Overlapping (CO) strategy, Variable Frequency (VF) strategy, Phase Shift (PS) strategy and Sub-Harmonic Pulse Width Modulation (SHPWM) i.e. Phase Disposition (PD) strateg...

Abetmct A concept of optimal surplus harmonies distribution in selective harmonic elimination PWM teehnique for multilevel inverters is introduced in this paper. There m e several performance indexes that fan he optimized in PWM inverters, e.g., distortion factor, current or voltage total harmonic distortion, or efficiency. Minimisation of magnetic noise is selected as an example here. Several ...

Alternating current (AC) electrical drives mainly require smaller (or torque) ripples and lower total harmonic distortion (THD) of voltage for excellent drive performances. Normally, in practice, to achieve these requirements, the inverter needs be operated at high switching frequency. By operating frequency, size filter can reduced. However, which oftenly employs insulated gate bipolar transis...

In this paper, a proposed efficient solution for an important power quality problem focused on harmonic distortion in the source current is introduced by using Shunt Active Power Filter (SAPF) controlled sinusoidal control strategy which based instantaneous active and reactive theory (Sinusoidal PQ-theory). As part of controller, there PI-Controller enhances APF controller performance when tuni...

Thyristor rectifiers are widely used in electric railways in order to control the speed. As a consequence of their usage in addition to substantial input lead current, an enormous amount of harmonics is injected into the grid. To avoid such harmonics as well as reactive power compensation, reactive power hybrid filters consisting of active and passive filters are utilized. Regarding different p...

This project proposed the new distortion power quality index to replace the previously proposed index. Its computation was carried out based on the load composition rate (LCR) and Euclidean norm of total harmonic distortions (THDs) of the measured voltage and current waveforms at the point of common coupling (PCC). Based on the proposed PQI, the harmonic pollution ranking, which indicates how m...