Carrier current protection scheme is mainly used for the protection of the long transmission line. … The receiver converts the received carrier current into a DC voltage that can be used in a relay or other circuit that performs any desired function. The voltage is zero when the carrier current, is not being received.
Which type of protection is carrier current protection?
Carrier-current protection is the most widely used scheme for the protection of Extra High Voltage (EHV) and Ultra High Voltage (UHV) power lines. The carrier signal is directly coupled to the power line itself which is to be protected.
What are the advantages of carrier channel protection over pilot wire protection?
Advantages of Carrier-Current Channel: High-frequency signal transmission along overhead power lines offers the following advantages over pilot wires: No separate wires are needed for signalling, as the power lines themselves carry power as well as communication signals. Hence the capital and running costs are lower.
What is carrier current equipment?
Carrier current transmission, originally called wired wireless, employs guided low-power radio-frequency signals, which are transmitted along electrical conductors. The transmissions are picked up by receivers that are either connected to the conductors, or a short distance from them.
Which component is carrier current protection Mcq?
Line trap and coupling capacitors are used for carrier current protection in which.
What are the disadvantages of overcurrent relay?
The use of IDMT overcurrent relay has some disadvantages. Most of the problems relate to the coordination between the main and the backup relay. One of the problems faced by the overcurrent relay is fault severity variation.
What is the purpose of backup protection?
The backup protection provides the back up to the main protection whenever it fails in operation or its cut out for repairs. The backup protection is essential for the proper working of the electrical system.
Why is PLCC used in a substation?
PLCC in modern electrical power system substation is mainly used for following purpose: Carrier protection relaying of transmission line so that: Inter trip command can be issued by relay due to tripping of circuit breaker at any one end.
Which protection scheme is used for the protection of high and EHV transmission line?
Distance protection is a widely used protective scheme for the protection of high and extra high voltage (EHV) transmission and sub-transmission lines. This scheme employs a number of distance relays which measure the impedance or some components of the line impedance at the relay location.
What are the drawbacks of differential protection?
Problems Encountered in Differential Protection of Transformer:
- Unmatched characteristics of CTs.
- Ratio change as a result of tapping.
- Magnetizing inrush current.
What is Unit protection?
Unit protection is designed to operate for abnormal conditions inside the protected zone while remaining stable for abnormal conditions outside the protected zone. This scheme requires current to be measured at each end of the zone.
What are current carriers?
Current carriers: The charged particles which constitute an electric current in solids, liquids and gases are known as current carriers.
What is bus bar protection?
Busbar protection is a protection scheme meant to protect the busbar from electrical fault. … The main purpose of this busbar is to increase the reliability of power system by maintain the evacuation of power in case of tripping of any feeder due to fault.
Which of the following carrier frequency is used in a carrier current protection?
The signals generated in a carrier-current protection scheme are at a frequency between 50 and 500 kHz.
What is UV relay?
A relay that has contacts that operate when the voltage drops below a set voltage. Undervoltage relays are used for protection against voltage drops, to detect short-circuit faults, etc.