The modular multilevel converter is improved topology for high-voltage, high-power applications since the cascaded sub modules can generate high-voltage waveforms with excellent harmonic performance at low switching frequencies. Many publications have been presented on the modulation and control of this converter type, some of which are based on phase-shifted carrier modulation. This paper pres...

Voltage sags are the most common power quality disturbance usually associated with power system faults, which can cause huge economic loss, making it the focus of emerging research. The proposed voltage sag detection technique for a single-line-to-ground (SLG) fault is presented using the PMU measurement data for improving the power quality. Various voltage sag detection techniques have been di...

Direct current (DC)-link voltage ripple analysis is essential for determining harmonic noise and for DC-link capacitor design and selection in single-phase pulse-width modulation (PWM) inverters. This paper provides an extensive theoretical analysis of DC-link voltage ripple for full-bridge (H-bridge) inverters, with simulation and experimental verifications, considering a DC source impedance (...

This paper proposes and validates models to accurately represent STATic Synchronous Shunt COMpensators (STATCOM) in voltage and angle stability studies of powers systems. The proposed STATCOM stability models are justified based on the basic operational characteristics of this Flexible AC Transmission System (FACTS) controller for both phase and PWM control strategies. These models are first va...

this paper presents the new topology of three phase on line uninterruptible power supply (ups) by employing t-source inverter (tsi) with maximum constant boost pulse width modulation (pwm) control and the results are compared with the conventional uninterruptible power supply (ups). the conventional ups consists of voltage source inverter (vsi) with step up transformer or dc-dc booster which de...

The role of the liquid-crystal layer in the phase-shifting shearing interferometer that was proposed by Griffin [Opt. Lett. 26, 140 (2001)] is analyzed. An extra voltage-dependent phase difference is produced when the phase retarder is oriented at an angle from the optical axis of the laser beam such that the interferogram will not repeat itself after a 2pi phase change of the liquid-crystal re...

Flexible AC transmission systems (FACTS) devices can control power flow in the transmission system to voltage source as it can inject an almost sinusoidal voltage of variable and controllable amplitude and phase angle, in series with a transmission line. Most of the injected voltage, which is in quadrature with the line current, provides the effect of inserting an inductive or capacitive reacta...

This paper deals with conceptual study of unified power quality conditioner (UPQC) during voltage sag and swell on the power distribution network and researches profoundly on the coordinated control of UPQC (Unified Power Quality Conditioner). By analyzing the radical reasons of coupling effect between UPQC series unit and shunt unit, a simple and practical coordinated control strategy for UPQC...

Theintegrationofrenewableenergysystemsisenhancingindailylifeforsupplyingtheglobaldemandforelectricenergy.Theconcerningproblemwiththeintegrationofsuchdistributedgeneration(DG)isislanding.Itmaydamagetheconsumersandequipment.AspertheIEEE1547DGintegrationspecificationsitmustbeidentifiedin2seconds.Inthisarticleanovelpassiverecognitionapproachoccupyingontherateofchangeofphaseanglebetweenpositiveseque...