To restore the load voltage, Dynamic Voltage Restorer (DVR), which is installed between the supply and a sensitive load, should inject voltage and active power from DVR to the distribution system during voltage sag. Due to the limit of energy storage capacity of DC link, it is necessary the minimize energy injection from DVR. In this paper the techniques of the supply voltage sag compensation i...

The quality of voltage and current delivered by the power utilities has become a major concern of the modern industries. The common power quality problems are voltage sag, voltage imbalance, transients, interruptions and harmonics. The two major power quality disturbances are voltage sag and harmonic distortion. In this paper, a Quality Power Provider (QPP) based on voltage source inverter is m...

Dynamic Voltage Restorer is a power electronic device that can protect sensitive loads from various disturbances in the power supply. This paper presents the study & analysis of DVR and power quality problems, voltage sag & swells with its application at Low Voltage and Medium Voltage level. DVR is always connected in series with the distribution feeder. The basic principle of a DVR is simple, ...

Power quality is one of the areas that the power sector is worried about. Power quality is the measure of practical system resemblance to ideal system. Voltage quality can be defined as the maintenance of voltage waveform shape close to ideal shape with proper magnitude and frequency. Even a slight change in voltage of the system can cause serious damage to the power system. Sensitive loads can...

This paper presents the custom power devices to improve the power quality by using a Distribution Static Compensator (DSTATCOM). Custom power is a technology driven product and service solution which embraces a family devices such as DSTATCOM. It describes the techniques of correcting the supply voltage sag in a distribution system by DSTATCOM. The steady state performance of system with or wit...

The operation and control of fuel cell (FC) distributed generation (DG) systems combined with energy storage are studied in this paper. For this purpose, modeling of hybrid FC/energy storage DG system is developed. Dynamic models for proton exchange membrane fuel cell (PEMFC), supercapacitor, DC–DC converters, and grid connected inverter are described. Then a PI controller for the FC converter ...

In this paper, the voltage sag ride-through capabilities of the line-connected electrically excited synchronous machine with damper windings (EESM) is investigated. We will design an algorithm for voltage sag ride through by controlling the flux. Two aspects are investigated, first the capability to keep the nominal speed and second the damping of speed oscillations. We will show through simula...

detection & classification of power quality (pq) disturbances are the most important problems in distribution systems. in this paper, a new approach for the detection and classification of single and combined pq disturbances is proposed which utilizes fuzzy logic and particle swarm optimization (pso) algorithms. in this approach, first suitable features of the waveform of pq disturbances ar...

In this paper improvement in voltage sag by using firefly algorithm optimized fuzzy controller is described. DSTATCOM is the FACTS device used in voltage sag improvement. Firefly algorithm optimization is used to optimize the if-then rules of the fuzzy controller. In this system a DSTATCOM is placed in a three phase system to control the voltage sag. A fuzzy controller is designed to control th...