Voltage sags in the electric power system are mostly due to faults in the power system. Voltage sag is characterized by its magnitude (the retained voltage), phase-angle jump, unbalance in the sag in the three phases, and duration. Type of transformers in the electrical system is the important parameter influencing the characteristic of sag at the node where sensitive loads are connected. For s...

Voltage sag compensator is very important in power quality. Its performance also depends on the types of sag detection techniques used. Sag detection technique determines the dynamic performance of a voltage-sag compensator. Many techniques have been introduced to measure and to detect voltage sag, such as RMS-Value Evaluation and Peak-Value Evaluation. Unfortunately, most of the techniques req...

This paper proposes a low complexity control scheme for voltage of dynamic restorer (DVR) in three-phase system. The employs the fractional order, proportional-integral-derivative (FOPID) controller to improve on DVR performance order enhance power quality terms response time, steady-state error and total harmonic distortion (THD). result obtained was compared with proportional-integral (FOPI),...

Abstract. The design of a Dynamic Voltage Restorer that is suitable for compensating regional voltage sags in 10kV distribution system is introduced in this paper. The design of the main circuit based on cascaded H-bridge, the device for energize DVR and the transformer-less coupled circuit are presented. For the voltage sags in neutral point non-grounded system, a reference voltage calculation...

This paper presents the design and develops of voltage acceptability curves for LED lamps. It is done with the mathematical representation of DC bus voltage of LED lamps internal ballast circuit during voltage sags. First, experimental analysis was done to determine the effect of voltage sag of LED lamp. From the findings on the variation of DC bus voltage during voltage sag, a mathematical equ...

While early FACTS devices consisted mainly of thyristor-controlled/switched RLC/transformer components, the newer generation is based on the self-commutated voltage-source power converter. Different shunt FACTS devices, namely Static VAR compensator (SVC) and Static Synchronous Compensator (STATCOM), Dynamic voltage restorer (DVR) in transmission line using the actual line model. This paper des...

The design of a Dynamic Voltage Restorer that is suitable for compensating regional voltage sags in 10kV distribution system is introduced in this paper. The design of the main circuit based on cascaded H-bridge, the device for energize DVR and the transformer-less coupled circuit are presented. For the voltage sags in neutral point non-grounded system, a reference voltage calculation method wi...