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.
In this paper, the impact of using the Thyristor Controlled Voltage Regulator (TCVR) on short-circuit calculations is studied for a high voltage transmission Une in case of a phase to earth fault in ...the presence of a fault resistance (R^sub F^). A 400 kV single transmission line, in the Algerian power network, is used for this study where the Une is compensated by TCVR FACTS device to control the voltage and active poorer of the Une. The impact of the fault resistance is studied to reflect its effect on short-circuit calculations including symmetrical current components, transmission line currents, voltage symmetrical components, and transmission line voltages, without and with TCVR. The obtained simulation results match the presented theoretical analysis.
This research paper presents a comparative study of the performance of distance protection for transmission line 400 kV in Algerian transmission networks at Group Sonelgaz (Algerian Company ...ofElectricity and Gas) compensated by two different series Flexible Alternative Current Transmission System (FACTS) i.e. GTO Controlled Series Capacitor (GCSC)and Thyristor Controlled Series Capacitor (TCSC) connected at midpoint of an electrical transmission line.The facts are used for controlling transmission voltage, power flow and reactive power in high power transfer levels. This paper studies the effects of angle variation and controlled GCSC and TCSC insertion on the total impedance of a transmission line protected by MHO distance relay. The modified setting zone protection (resistance and reactance) in capacitive and inductive boost mode for three forward zones and one reverse zone are investigated in order to improve the performances of distance protection. The simulationresults are performed in MATLAB software.
The use of Distributed Renewable Energy Sources in the electrical network has expanded greatly. But, integration of these resources into distribution systems caused more problems in protection ...related issues such as mis-coordination, and changes the direction and value of fault currents. When connecting new D-RES to electrical power distribution networks, it is required to re-coordinate Directional Over-CurrentRelays (DOC-Relays) to ensure the continuity of the power transmission when the short circuits take place. This work presented a Particle Swarm Optimization (PSO) algorithm to determine two independent variables called Pickup current (Ip) and Time Dial Setting (TDS) for optimal setting of relays. From analysis result, the impacts of RES location in the distribution system on DOCRs had been observed on the optimal relays settings
In this paper, a low cost and an easy to implement solar tracker system is presented. The design of the system is based on the fuzzy reasoning applied to crisp sets. In this case, it can be easily ...implemented on general purpose microprocessor systems. Four light sensitive devices, such as LDR, photodiodes or phototransistors are mounted on the solar panel and placed in an enclosure. The four light detectors are screened from each other by opaque surfaces. Each pair of the light sensors is used to inform the controller on the orientation of the solar panel vertically and horizontally respectively.
This paper presents the impact of GTO Controlled Series Capacitor (GCSC)
parameters on the Inverse Definite Minimum Time (IDMT) Directional
Overcurrent Relay (DOCR) based on the International ...Electrotechnical
Commission (IEC) standards. The DOCR is used to protect a single 400 kV
transmission line of the Algerian transmission network which belongs to the
Algerian Company of Electrical and Gas (Group Sonelgaz). The effects of GCSC
on transmission line protected parameters as well as fault current and DOCR
operation time in the presence of phase to earth fault with fault resistance
are investigated considering three scenarios.
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Protective relays coordination is the process of determining the exact relay settings such that the relay closes to the fault would operates faster than other relays. The operating time of each relay ...depends on two independent variables called Pickup current (Ip) and Time Dial Setting (TDS). In this paper, a PSO algorithm has been presented to determine the coordination of Directional Over-Current Relays (DOCRs) in presence of multi-system FACTS devises. From the simulation result and analysis, the impact of TCSC location in the in 33-bus distribution system on Directional Over-Current Relays has been observed on the optimal relays settings as well as the effectiveness of the proposed algorithm in finding optimal coordination of directional over-current relays.
With 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.
This paper presents the effect of three series Flexible AC Transmission System (FACTS), i.e., Thyristor Controlled Series Capacitor (TCSC), GTO Controlled Series Capacitor (GCSC) and Thyristor ...Controlled Series Reactor on the short circuit calculation of a 400 kV electric transmission line, in the presence of phase to earth fault with fault resistance. The study deals with a 400 kV single transmission line in the Algerian Electrical Company compensated by three compensators connected at midpoint of the line to control reactive power and apparent transmission line reactance. The simulations results concern the effects of fault conditions, i.e., fault resistance varied between 0 Ω-50 Ω and fault location varied between 50%-100% on the parameters of short circuit calculation. The results show also that care must be taken in order to increase the performance of system protection in the presence of series FACTS devices on transmission line, mainly the variation of fault current.
Optimal coordination of direction overcurrent relays of the power systems, in the presence of GTO Controlled Series Capacitor installed on meshed power system is studied in this paper. The ...coordination problem is formulated as a non-linear constrained, mono-objective optimization problem. The objective function of this optimization problem is the minimization of the operation time of the associated relays in the systems and the decision variables are the time dial setting and the pickup current setting of each overcurrent relay. To solve this complex non linear optimization problem, a variant of evolutionary optimization algorithms, named Krill Herd Algorithm is used. The proposed algorithm is validated on IEEE 14-bus transmission network test system, considering various scenarios. The obtained results show a high efficiency of the proposed method to solve such complex optimization problem, in such a way the relays coordination is guaranteed for all simulation scenarios with minimum operating time for each relays. The results of objective function are compared to other optimization algorithms.
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