Flexible direct current (DC) transmission network technology is an effective method for large capacity clean energy access to power grids, but the DC short-circuit fault detection for it is a difficult problem. In this paper, the pole-to-ground fault transient characteristics in a multi-terminal DC power grid, based on overhead transmission lines and DC circuit breakers, are analyzed firstly. T...

In this paper, transient stability improvement using bridge type fault current limiter (FCL) is presented in single machine infinite bus (SMIB) system with a double circuit transmission line. Three single-phase sets of the proposed FCL are installed at the beginning of feeder. The proposed FCL inserts an inductance and a resistance in the fault current pass. The insertion inductance and resista...

An irregular activity on electric power distribution feeder, which does not draw adequate fault current to be detected by general protective devices, is called as High impedance fault (HIF). This paper presents the algorithm for HIF detection based on the amplitude of third and fifth harmonics of current, voltage and power. This paper proposes an intelligent algorithm using the Takagi SugenoKan...

At the time of power swing the measured impedance lies inside the relay operating region. There is undesired tripping of Distance relay during power swing without having any fault. So relay must be blocked & must trip after a fault occur during power swing. This paper presents new technique to detect fault during power swing. In the proposed technique process starts by simulating the double tra...

This paper presents a synchronized phasor measurement-based wide-area backup protection scheme which uses the magnitude of sequence voltages of buses at a system protection centre to identify the faulted bus closest to the fault and faulted line. The technique is tested for various faults including simultaneous faults in various systems with interconnections. The scheme is found to be accurate ...

With wide spread use of sensitive nonlinear electronic devices the switching transients are capable of degrading the quality of power. Utilities often switch the shunt capacitor banks to cope up with sagging voltage levels, thereby generating transients, which travel into the network of end users. Capacitor switching can cause over voltage, resonance and in advert tripping of Adjustable Speed D...

Medium voltage distribution systems of some countries are mostly noneffectively grounded systems, and most of the distribution automation systems do not have the function of locating the fault section for single phase-to-ground fault. This paper presents a method of fault section location based on the characteristic of the phase current difference. It makes a deep analysis based on instantaneou...

This paper is based on the EL mathematical model of the MMC synchronous rotating coordinate system, derived the MMC passive control law, the inner ring current passive controller is designed and the AC voltage controller is set. In order to restrain the negative sequence current caused by the network voltage unbalance or asymmetric AC system fault, the positive and negative sequence of independ...

This paper expands a nonlinear fuzzy based control strategy applied to a variable speed Wind Energy Conversion System WECS founded on Doubly Fed Induction Generator DFIG. As power network assists a high wind energy emergence, the studied WECS represents a wind farm WF of 500MW connected to the Grid and dispatched in such a way that it can contribute to grid frequency control with delivering a s...

Distributed generation is a form of electric power privatization. Consumers install their own power station to supply the local loads and/or share in the utility loads. Many protective problems have been developed due to the existence of these distributed generations. However, a protective strategy should be developed to protect the system and the generator itself from different hazards. One pr...