Impact of apparent reactance injected by TCSR on distance relay in presence phase to earth fault

This research paper presents the impact study of apparent reactance injected by series Flexible AC Transmission System (FACTS) i.e. Thyristor Controlled Series Reactor (TCSR) on the measured impedance of a 400 kV single electrical transmission line in the presence of phase to earth fault with fault resistance. The study deals with an electrical transmission line of Eastern Algerian transmission networks at Group Sonelgaz (Algerian Company of Electrical) compensated by TCSR connected at midpoint of the transmission line. This compensator used to inject voltage and reactive power is controlled by TCSR. The simulations results investigate the three impacts of the apparent reactance injected by TCSR (XTCSR) on transmission line protected by distance relay protection. The impacts concern the active and reactive power, the line impedance (reactance and resistance), and the short circuit parameters (symmetrical currents, line currents, symmetrical voltages and line voltages as well as the measured impedance by relay (resistance and reactance) in the presence of earth fault These impacts are investigated in order to improve the performances of distance relay protection. More the impact of XTCSR by three TCSR for cases studies is presented

Fault Location Effect on Short-Circuit Calculations of a TCVR Compensated Line in Algeria

This research work investigated the effect of fault location on short-circuit calculations for a high voltage transmission line equipped with a novel FACTS device, namely Thyristor Controlled Voltage Regulator (TCVR). This main function of this device was to control the voltage and active power of the line. The paper considered a study case for a 220 kV transmission line, in the Algerian transmission power network, which was subjected to a phase to earth fault in the presence of a fixed fault resistance. The paper presented theoretical analysis of the short-circuit calculations which was confirmed by the illustrated simulation results. Simulation results showed the impact of the fault location on the symmetrical current and voltage components of the line, and transmission line phase currents and voltages; before using TCVR and in the presence of TCVR for both cases of positive and negative TCVR controlled voltage

Effects of Shunt FACTS Devices on MHO Distance Protection Setting in 400 kV Transmission Line

Abstract This paper presents a study on the performances of distance relays setting in 400 kV in Eastern Algerian transmission networks at Sonelgaz Group (Algerian Company of Electricity) compensated by shunt Flexible AC Transmission System (FACTS). The facts are used for controlling transmission voltage, power flow, reactive power, and damping of power system oscillations in high power transfer levels. The direct impacts of SVC devices i.e. Thyristor Controlled Reactor (TCR) and the Thyristor Switched Capacitors (TSC) insertion, on the total impedance of a transmission line (Z AB ) protected by MHO distance relay are investigated. The modified setting zones protections (Z 1 , Z 2 and Z 3 ) have been calculated in order to improve the performances of distance relay protection and prevent circuit breaker nuisance tripping. The simulation results are performed in MATLAB software and show the direct impact of the thyristors firing angle (α) on the total impedance of the protected line

Mixed Integer Optimization of IDMT Overcurrent Relays in the Presence of Wind Energy Farms Using PSO Algorithm

This paper presents an optimal coordination of inverse definite minimum time (IDMT) directional overcurrent relays (DOCR) in the presence of Wind Energy Farms (WEF). Firstly, the impact of WEF on the relays coordination is focused, after that we search for the new relays setting to ensure an optimal coordination of the relays. The coordination problem is formulated as a constrained nonlinear mono-objective optimization problem. The objective function of this optimization problem is the minimization of the operation time of the associated relays. In terms of decision variables; two types of optimizations are considered in this paper, namely: real parameter optimization where, the time dial setting (TDS), and the pickup current setting (IP) are considered as the real decision variables of the optimization problem and the mixed integer optimization, where the IEC curve characteristic of each relay is added to the previous variables as an integer decision variable. The characteristics of the relays are always chosen arbitrary or by trial and error method. To solve this constrained non linear optimization problem, the particle swarm optimization method is used. The proposed method is validated on IEEE 8-bus power transmission test systems considering various scenarios

Usporedna analiza greške uzemljenja za praktični slučaj transmisijske linije s različitim FACTS uređajima

Due to the rising power demand and increasing population worldwide, electrical power networks have been extensively growing and striving to satisfy the escalating loads. This necessitates the need for using Flexible AC Transmission System (FACTS) devices which have become indispensable during normal and abnormal operating conditions. This paper investigates the impact of using series FACTS devices, namely Thyristor Controlled Series Capacitor (TCSC), GTO Controlled Series Capacitor (GCSC) and Thyristor Controlled Series Reactor (TCSR), on the impedance and power flow of a practical 400 kV transmission line in the Algerian power network. It also investigates the effect of varying the fault resistance on short-circuit calculations in the case of a phase to ground fault that occurs at the end of the compensated line. Analytical formulas of the employed FACTS devices, the system model under fault and short-circuit calculations are deduced and presented in the paper. Simulations results obtained using MATLAB are demonstrated for the compensated line and without compensation. These simulations are compared to show the effect of using these devices for the studied cases. It is concluded that GCSC provides better performance in the active and reactive power flow of the line under normal operating conditions and in reducing the fault current during abnormal operating conditions when the fault resistance increases. On the other hand, TCSR shows a better performance in maintaining higher voltages under fault with the increase of fault resistance.Zbog rastuće potražnje za električnom energijom i porasta svjetske populacije elektroenergetske mreže ubrzano rastu i podnose sve veće terete. Takav razvoj situacije doveo je do korištenja fleksibilnih AC transmisijskih sustava (FACTS) koji su postali nezamjenjivi tijekom normalnih i narušenih uvjeta na mreži. U ovom se radu istražuje utjecaj korištenja FACTS uređaja, tiristorski upravljani serijski kondenzatori, GTO upravljani serijski kondenzatori i tiristorski upravljana serijska reaktancija, na impedanciju i tok snage kod 400 kV transmisijske lijene u alžirskom elektroenergetskom sustavu. Istražuje se i utjecaj promjene otpora greške pri izračunu kratkog spoja u slučaju spoja faze na zemlju koje se događa na krajevima linije. Analitičke formule korištenog FACTS uređaja, model sustava s greškom i izračun kratkog spoja su izvedeni i prikazani u radu. Simulacijski rezultati dobiveni korištenjem MATLB-a prikazani su za linije sa i bez kompenzacije. Simulacije su uspoređene kako bi se prikazao učinak korištenja različitih uređaja. Zaključeno je da GTO upravljani serijski kondenzatori ima bolja svojstva kod toka radne i jalove snage kroz liniju tijekom normalnog rada i kod smanjenja struje greške tijekom narušenih uvjeta kada otpor greške raste. S druge strane, tiristorski upravljani serijski kondenzatori bolji su kod održavanja visokog napona tijekom greške uz povećanje otpora greške

Investigation of TCSC Controller Effect on IDMT Directional Over-current Relay

AbstractWith the presence of FACTS controllers in power system transmission for enhancing the power system controllability and stability, the problem of coordinating protective relays becomes more challenging. The over-current relay is widely used in many protection applications throughout distribution network and theIDMT directional over-current Relay is one of the most important protection systems on transmission lines. Its function would generally be changed in presence of FACTS devices.In this paper a study for obtaining the direct effects of the varying reactance of the TCSC with respect to the firing angle alpha on short-circuit parameters of three phase fault and DOCR operating time is investigated. The simulation of the linear programming technique is performed in Matlab software environment. The case study is compared between compensated and uncompensated system