Performance of Distance Relays on Shunt—FACTS Compensated Transmission Lines

Ebrahimi

Prot Control Mod Power Syst

2017

Flexible ac transmission system (FACTS) controllers, especially the series-FACTS controllers, affect the operation of distance relays and can lead to the relays under/over-reaching. This paper aims to demonstrate the effects of static synchronous series compensator (SSSC) and series capacitive compensation (SCC), as two important series compensators, on the distance protection using theoretical and computational methods. The results of the investigation are used to develop a feasible and adequate method for eliminating the negative effects of these devices on the distance relays. The developed method measures the voltages at terminals of the SSSC and SCC by phasor measurement units (PMUs) which are then transmitted to the relay location by communication channels. The transmitted signals are used to modify the voltage measured by the relay. Different operation types and conditions of SSSC and SCC, and different faults such as phase-to-phase and phase-to-ground faults are investigated in simulations. Since the modeled distance relay can measure the fault resistance, trip boundaries are used to show the performance of the presented method. Results show that the presented method properly eliminates the negative effects on the distance relays and prevents them from mal-operation under all fault resistance conditions.

Section: Introductionmentioning

confidence: 99%

Active power based distance protection scheme in the presence of series compensators

Ebrahimi

Prot Control Mod Power Syst

2017

Journal of Electrical Engineering and Technology

“…Majority of the researches have surveyed these effects on impedance relays such as the distance relays of transmission lines and loss-of-excitation (LOE) relays of synchronous generators, which both operate based on the impedance measurements. The distance relay performance is analyzed in [1][2][3][4][5][6][7][8][9][10][11] in the presence of FACTS controllers. These studies include three major investigation categories; which deal with; a) shunt-FACTS such as static Var compensator (SVC) and static synchronous compensator (STATCOM) [1][2][3][4], b) series-FACTS such as SSSC and thyristor controlled series capacitor (TCSC) [5][6][7], and c) shunt-series-FACTS such as unified powerflow controller (UPFC) and generalized interline powerflow controller (GIPFC) effects [8][9][10][11].…”

Section: Introductionmentioning

confidence: 99%

Modified Transmission Line Protection Scheme in the Presence of SCC

Naeini¹,

Vaseghi²,

Mahdavian³

2017

-Distance relay identifies the type and location of fault by measuring the transmission line impedance. However any other factors that cause miss calculating the measured impedance, makes the relay detect the fault in incorrect location or do not detect the fault at all. One of the important factors which directly changes the measured impedance by the relay is series capacitive compensation (SCC). Another factor that changes the calculated impedance by distance relay is fault resistance. This paper provides a method based on the combination of distance and differential protection. At first, faulty transmission line is detected according to the current data of buses. After that the fault location is calculated using the proposed algorithm on the transmission line. This algorithm is based on active power calculation of the buses. Fault resistance is calculated from the active powers and its effect will be deducted from calculated impedance by the algorithm. This method measures the voltage across SCC by phasor measurement units (PMUs) and transmits them to the relay location via communication channels. The transmitted signals are utilized to modify the voltage signal which is measured by the relay. Different operating modes of SCC and as well as different faults such as phase-to-phase and phase-to-ground faults are examined by simulations.

“…The model of STATCOM is proposed firstly and then the analytical results based on symmetrical component transformation for SLG fault on a transmission line employing STATCOM are described and finally the simulation results show the impact of STATCOM on distance relay characteristics. [2] …”

Section: Introductionmentioning

confidence: 99%

Impact Analysis of Statcom on Distance Relay Performance

2016

IJAERD