What does a substation do?

1 Answer

Answer :

At  the  substations,  power  is  boosted  up  for  long  distance  transmission.

Related questions

Description : What is the first equipment of the substation connected to the incoming transmission line?

Last Answer : Lightning arrestor is the first equipment of the substation connecting the incoming transmission lines. It protects other substation equipment from lightning and switching surges by suppressing them to ... between both the ends of major equipment such as power transformers for protection.

Description : What are different Bus bar materials used in Substation?

Last Answer : Busbars are generally made of copper and Aluminum. Aluminim has the advantage of one third the weight of the copper and also Aluminum requires less maintenance and proper use of alloys provide necessary rigidity required for bus material. Aluminum is used widely in EHV and HV stations

Description : What are the different electrical clearances in Substation?

Last Answer : Ground Clearance: This is the minimum distance between any live conductor and the earth or ground. Phase Clearance: It is the clearance between the different phases in a circuit or same phases in different ... The limits of work section may be ground or the platform on which the person is working.

Description : What are the different substation components

Last Answer : Circuit Breakers, Disconnecting switches, Grounding switches, Current Transformers, Potential Transformers or Capacitor voltage Transformers, Line Traps, Lightning Arrestors, Power Transformers, Shunt ... Station Buses and Insulators, Grounding system, Series capacitors and shunt capacitors.

Description : State the condition for selecting site for distribution substation. 

Last Answer : Following condition should be considered while selecting site for distribution sub-station:-  1. Near load center :  Sub-station should be located near load center to reduce cost of Transmission and ... free from earthquake :  To avoid damage to sub-station area should be free earth quake. 

Description : State the classification of distribution substation. 

Last Answer : The classification of distribution substation. 1. Pole mounted distribution substation 2. Plinth mounted distribution substation 3. Compact/prefabricated distribution substation 4. ... Indoor distribution substation 6. Outdoor distribution substation 7. Mobile distribution substation 

Description : What is the purpose of auxiliary controller in substation?

Last Answer : The systems of substation auxiliaries ensure operation of substations providing internal consumers of substations with operating direct and alternating currents. Any breakdown (loss) of auxiliary systems ... whole substation, as well as serious problems during its subsequent putting into operation.

Description : Classification of Substation According to Method of Construction

Last Answer : Classification of Substation According to Method of Construction:- 1. Indoor Substation 2. Outdoor Substation 3. Gas insulated Substation 4. Underground Substation 5. Pole mounted substation 6. Plinth Substation 7. Compact/prefabricated substation

Description : Isolator in substation is open under ___________ condition?  (A) No load (B) Short circuit (C) Full load (D) None of the above

Last Answer : no load

Description : Why EHV busbars are hallowed and circular?

Last Answer : Answer: To avoid corona effect

Description : Factors on which material of station busbar depends?

Last Answer : Some of the factors on which station busbar depends are: Current Carrying capacity Short Circuit Stresses Establishing minimum electrical clearances

Description : For distribution network which type of Switching scheme is employed?

Last Answer : For distribution network Ring Main busbar scheme is employed. It has the provision that if power interruption occurs to one bus section due to maintenance or fault, power can be fed the bus from other side of the power system.

Description : Which type of bus arrangement is costlier and more reliable?

Last Answer : One and half breaker scheme is most reliable and costlier scheme. In one and half breaker scheme 3 circuit breakers are provided for 2 bus-bars. Hence the name is coined as One and half breaker scheme

Description : What are different types of busbar arrangement Schemes in Substations?

Last Answer : Different switching schemes or busbar arrangement scheme employed in switch-yard are: Single Bus Scheme Double bus single breaker scheme Main and Transfer busbar scheme Double bus single breaker scheme Breaker and half scheme Ring main bus scheme

Description : What is the neutral point earthing and its advantages?

Last Answer : In substation all the neutrals of rotating machines, transformers, busbars and other equipment are connected to ground. Some of the advantages are: Earth fault protection is based on the method of ... , grounding of neutral helps to reduce the over-voltages which occur on the one healthy phases

Description : What is the significance of Corona rings in substations?

Last Answer : It is observed that corona discharge occurs mostly at sharp corners, edges near the conductor fixing points. Corona rings also called grading rings are hallow metallic rings having large diameter ... is reduced to much lower value Corona discharge is eliminated Dust deposition is also minimized

Description : What are the disadvantages of corona?

Last Answer : Some of the disadvantages of corona are: Corona causes power loss Corona causes unacceptable noise Corona cause radio interference

Description : What is Basic Impulse Level (BIL)?

Last Answer : Basic Impulse Level (BIL) refer to the peak value of lightning impuse voltage withstand capability of the equipment

Description : What is creepage distance?

Last Answer : Creepage distance is the shortest distance between two conducting points along the surface of the insulating material.

Description : What are different insulators employed in substations?

Last Answer : Some of the insulators employed in substations are: Pin insulators Post insulators Strain insulators Suspension insulators Hallow apparatus insulators Dead-end insulators Solid core insulators

Description : Which of the device is employed in substation to limit the short circuit current in the power system: a) Shunt condenser b) Reactor c) Series capacitor d) Shunt capacitor

Last Answer : Ans: B

Description : In order to improve the power factor ___ device is employed in the substation a) Synchronous condenser b) Synchronous reactor c) Series Capacitors d) None of the above

Last Answer : Ans: A

Description : Stones are provided in the substation to: a) To avoid fire accident by draining oil from transformer if leaks b) To avoid growing of weeds and plants c) To provide insulation d) All the above

Last Answer : Ans: D

Description : Locations where Gas Insulated Substation is preferred

Last Answer : Gas Insulated Substations are preferred in the places where land requirement for the substation is difficult such as in populated areas and highly polluted areas where outdoor switchyard is not ... pollution and saline environment. Under such case indoor GIS substation is very much helpful.

Description : What are different insulators used in substation

Last Answer : Different Insulators: Over head electrical conductors used for transmitting electric power is mostly bare and not covered with any insulation medium. The bare line conductors are ... Post insulators for support Stray arm insulators Shaft insulators Sectionalising insulators Connecting rod insulators

Description : In a substation the following equipment is not installed (a) exciters (b) series capacitors (c) shunt reactors (d) voltatre transformers

Last Answer : (a) exciters

Description : Draw a block diagram of WPP substation. State function of each block.

Last Answer : Block Diagram of WPP Substation: OR Wind Turbine : Converts wind power to rotational mechanical energy Gear Box: Transfer low speed to high. Generator: Converts rotational ... to DC and vice-versa of correct frequency. Transformer: Step up the voltage to grid level.

Description : State significance of earthing. Draw and explain pipe earthing. State the values of earth resistances for : (i) Substation (ii) Residential wiring (iii) H.T. Line (iv) L.T. Line

Last Answer : Significance of earthing:  * Earthing means connecting the body of the electrical equipment (it means the part which does not carries current under normal condition) to the earth. For example electrical equipment' ... surrounded by charcoal and salt.  the values of earth resistances for: 

Description : Write down the circuit breaker with their rating used in traction substation. Explain any one.

Last Answer : Circuit Breaker With Their Rating Used in Traction Substation: Rated capacity of a circuit breaker is 750Amps at 25 kV, 500MVA. Its overall tripping time is 0.14 seconds composed of 0.04 ... but in case of traction substation application, mostly Minimum Oil Circuit Breaker (MOCB) is preferred.

Description : Distributed under Creative Commons Attribution-ShareAlike - CC BY-SA.

Last Answer : Some important components/equipments in substation  As told earlier, the function of a substation is to receive power at some voltage through incoming lines and transmit it at some other voltage through ... range ammeter to indicate the line current. Version 2 EE IIT, Kharagpur 

Description : List any two Thermal Power Station in Maharashtra with their installed capacity. 

Last Answer :  Thermal Power Station in Maharashtra with their installed capacity :

Description : With a neat diagram explain doubly fed induction generator (DFIG). 

Last Answer : Diagram of Doubly fed induction generator (DFIG):  Explanation :-  DFIG can feed power through the stator as well as rotor to the grid. The stator is directly connected to the fixed frequency ... voltage is 690 V AC. So it must be step up to 33 KV to connect to power grid.  

Description : What are the criteria for selection of site for hydroelectric power plant?

Last Answer : Following Factors to be kept while site selecting for Hydro power plant:  1. It should be located where high rain fall occurs. 2. A large catchments area must be available to store water. 3. It ... 12. Cost of land should be less. 13. Skilled and unskilled man power should be available nearby.

Description : Explain the function of different parts of a typical nuclear power plant with neat sketch. 

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Description : Give the causes and impact and reasons of grid system fault. 

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Description : With a neat diagram explain pumped storage hydro power plant. 

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Description : Draw a layout of a thermo-chemical based power plant. 

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Description : Explain the choice of size and number of generator units in a power plant. 

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Description : Explain Squirrel Cage Induction Generator (SCIG) and also draw a diagram. 

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Description : Compare base load plant with peak load plant. 

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Last Answer : 1. Connected Load: It is the sum of load of all equipment's connected to supply system which are in use or not in use of each consumer. OR   The sum of connected load of all consumers ... is the maximum load which a consumer uses at a particular time period out of his total connected load. 

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