scholarly journals Three zone detection and distance relay co-ordination of power system protection

Author(s):  
Cholleti Sriram ◽  
Y. Kusumalatha

To secure the transmission lines against power system faults, the distance relays are mostly used. Distance relay has its own Resistance (R)–Reactance (X) characteristics. Co-ordination of different distance relays is necessary for the fast operation of circuit breaker. Various distance relays which are being tripped with respect to circuit breakers which are attached at individual buses faraway from each other. These relays will be operated with respect to the distance between the occurred fault and relay location. In this paper, detection of three zones using relay characteristics, co-ordination of distance relays and circuit breakers are shown with the faults placed at different locations of an IEEE Nine bus system using MATLAB/Simulink GUI environment. A comparison also made between the relays performance and circuit breaker tripping operation with respect to severe faults at different locations on IEEE Nine bus system.

2014 ◽  
Vol 1044-1045 ◽  
pp. 482-485
Author(s):  
Jin Hu Zhang ◽  
Zhen Yu Xu ◽  
Zhi Peng Su

The distance relays of transmission lines find limitations in the presence of series compensated capacitor. One of them is the distance relay setting issue, in which either over-reach problem or under-reach problem may occur. To deal with this issue, a differential equation based adaptive distance relaying setting method for series compensated line is proposed. As for it do not need to identify whether SC/MOV is in fault loop, not need to know the parameters and the operating states of SC/MOV/GAP, and furthermore, it can be realized without the iterative calculation, it is very suitable to be used for the distance relaying adaptive setting of series compensated line. Simple simulation results certificate the proposed adaptive setting method.


2015 ◽  
Vol 793 ◽  
pp. 65-69 ◽  
Author(s):  
Abadal Salam T. Hussain ◽  
Waleed A. Oraibi ◽  
Fadhel A. Jumaa ◽  
F. Malek ◽  
Syed F. Ahmed ◽  
...  

Electrical Power System protection is required to protectboth the user and the system equipment itself fromany fault, hence electrical power system is not allowed to operate without any protection devices installed. Power System fault is defined as the undesirable condition that occurs in the power system. Some of these undesirable conditions are short circuit, current leakage, ground faultand over-under voltage. With the increasing loads, voltages and short-circuit duty in power plant, over voltage protection has become more important today. Here, the component that had been used is PIC 16F877a microcontroller to control the whole system and especially on the circuit breakers as well as the LCT display unit is used to display the voltage level and type of generator that used to serve the load. Sensors are used to measure both thevoltage and the load. The controlled digital signal from PIC microcontroller is converted by using the digital analog converter to control the whole circuit. Thus a device called protective relay is created to meet this requirement. The protective relay is mostlyoften coupled with circuit breaker in a way that it can isolate the abnormal condition in the system.


2013 ◽  
Vol 415 ◽  
pp. 149-154
Author(s):  
Vinay Barhate

Power System fault is defined as undesirable condition that occurs in the power system. These undesirable conditions such as short circuit, current leakage, ground short, over current and over voltage. This paper is an attempt to design and fabricate inverse time over current protection relay using basic Microcontroller. The 8051 Microcontroller will cause the circuit breaker to trip when the current from load current reaches the setting value in the micro controller and generates a time delay for tripping as per the type of Characteristics for which it is designed, may it be IDMT or normal inverse, very inverse or extremely inverse over current Relay. First the load current need to measure in order to monitor it using current sensor and when such condition arise, it will isolate in the shortest time possible without harming the any other electrical devices. The current sensor processes the signal using current to voltage converter, precision rectifier, Analog to Digital convertor, peripheral interfacing devices with Microcontroller chip takes the suitable action of generating trip signal at appropriate time for expected pick up value of current. It is tested with laboratory setup and found working satisfactory.


Author(s):  
Win Win Tun ◽  
Ohn Zin Lin ◽  
Han Su Yin

Transmission lines are an important part of a power system. Transmission lines have high power transmission capacity and they are prone to faults of larger magnitudes. Various faults occur in transmission lines. Therefore, protection relays are necessary to protect transmission lines. The purpose of protection system is to interrupt the faulty section from the healthy section because the fault currents may damage the electrical equipments. One of the protection relays is distance relay and it is mainly used in transmission line. Sometimes these relay are used for backup protection. Distance relays for determining the impedance need the voltage and current. Transmission lines are typically protected by distance protection relay. Distance relays are considered of high speed class and can provide transmission lines. Nowadays, numerical distance relays have been used instead of using electromechanical and static distance relays. The proposed model was verified under different tests such as single line to ground (L-G) fault, double line to ground (L-L-G) fault, line to line (L-L) fault and three phase (L-L-L) fault. SimPower System was used for modelling and simulation of distance relay, transmission lines and faults. The simulation results were obtained from MATLAB software shows the feasibility of analysis of transmission line protection with mho type distance relay for single line to ground fault, double line to ground fault, line to line fault and three phase fault at different location of transmission lines. The difficulties understanding on operation of distance relay can be cleared by using MATLAB/SIMULINK software.  


Sign in / Sign up

Export Citation Format

Share Document