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...

This paper discusses design and simulation of dynamic voltage restorer for improve power quality & reduce the harmonics distortion of sensitive load. Electronics devices are very sensitive load against harmonics. DVR proposed not only to improve PQ but also to reduce HD due to the presence of non-linear load. The DVR consists of injection transformer, filter, ESS, VSI and control system. The ba...

The doubly-fed induction generator (DFIG) produces the reactive power to maintain its constant voltage operation. Firstly, the principle of the constant voltage control system for double-fed wind turbines is researched, and the influence on DFIG terminal voltage when the wind speed changes and the grid voltage sags is analyzed. Secondly, self-tuning PI control algorithm based on BP neural netwo...

Voltage sags normally do not cause equipment damage but can easily disrupt the operation of sensitive loads such as electronic Adjustable Speed Drives (ASD’s). Voltage sags cause a momentary decrease in DC-link voltage triggering an under voltage trip leading to nuisance tripping of adjustable speed drives (ASD’s) employed in continuous-process industries which contributes to loss in revenue. A...

To realize the self-healing concept of smart grids, an accurate and reliable fault locator is a prerequisite. This paper presents a new fault location method for active power distribution networks which is based on measured voltage sag and use of whale optimization algorithm (WOA). The fault induced voltage sag depends on the fault location and resistance. Therefore, the fault location can be f...

Any power quality disturbance waveform can be seen as superimposition of various oscillating modes. It becomes necessary to separate different components of single frequency or narrow band of frequencies from a non stationary signal to identify the causes which contribute to power quality disturbances. In this paper a method is proposed to detect and classify voltage sag causes based on Empiric...

This article uses a dynamic voltage restorer to tackle wide range of power quality issues, such as drooping and swelling, spikes, distortions, so on. The proportional controller, integrated controller (PI), adaptive neuro-fuzzy inference system (ANFIS) are proposed (DVR) controllers. control strategy's goal is employ an injection transformer mitigate for the needed keep load fixed. settings PI ...

Rat descending vasa recta (DVR) express a tetrodotoxin (TTX)-sensitive voltage-operated Na(+) (Na(V)) conductance. We examined expression of Na(V) isoforms in DVR and tested for regulation of Na(V) currents by calmodulin (CaM). RT-PCR in isolated permeabilized DVR using degenerate primers targeted to TTX-sensitive isoforms amplified a product whose sequence identified only Na(V)1.3. Immunoblot ...

This paper describes the causes of voltage sags in affecting process industries, their impacts on equipment operation, and possible solutions. The definition proposed focuses on system faults as the major cause of voltage sags. The sensitivity of different types of process industry equipment; including adjustable speed drive controls, programmable logic controllers, and motor contactors; is ana...