Ans : A Substation is an intermediate switching, transforming or converting station between the generating station and the low tension distribution network situated generally at the consumer’s load centre.

Ans : The Substation receives power from the generating station by a signal or more feeders at a high voltage, transforms the same to different distribution voltages and sends the power to different consumers through distribution network.

Ans : i) Indoor substation
ii) Outdoor substation
iii) Pole mounted substation
iv) Underground substation.

Ans : The Substation, of which the equipments are installed indoor for voltages upto 11kV because of economic consideration, is called as indoor Substation. In case of contaminated atmospheric condition these substations can be erected for voltages upto 66kV.

Ans: The Substation for voltage 33kV and above, where the equipments are installed outdoor because for such voltages, the clearance between conductors and the space required for various equipments becomes so great that it is not economical to install indoor, is called outdoor substation.

Ans : The following factors are to be considered in selection the site of an outdoor type substation :-
a) The site should be located closed to the centre of its supply area.
b) Sufficient land is to be available at a reasonable cost and without much difficulty for the construction of substation and the accommodation of the operating staff.
c) The site should be away from the densely populated locality.
d) The site should have easy access for having transport.

Ans : The outdoor type substation has the following advantages over indoor sub-station :-

1. All equipments are within sight and accessible ; faults and defects can therefore, be easily located and rectified.
   
2. The substation equipments can be spaced sufficiently apart.
3. The effect of fault in one section do not affect the healthy section.
4. The cost of erected is comparatively less as no large buildings are required to be erected to house the substation equipments.
5. The time required for erected is lesser.
6. Future extensions and alterations can be made without much difficulty.

The disadvantages of outdoor type substation are as follows :

1. As the equipments are open to atmosphere the influence of rapid fluctuation in ambient temperature, dust and dirt deposited on the equipments makes it necessary to install specially designed equipments which are costlier.
2. More space is required for the outdoor substation as buses and other live parts are bare and more clearance is necessary.
3. The various switching operations, fault repair and maintenance become difficult in rough and inclement weather.

Ans : Pole mounted substation is the outdoor type cheapest form of substation for voltages not exceeding 33kV in which the equipments are installed overhead on H-pole or 4-pole structure and electric power is almost distributed in localities through such substation.

Ans : In thickly populated areas where the available space for substation equipment and building is limited and cost of land is high, the substation equipment are placed under ground and then it is said to be underground substation which requires more careful consideration than other types of substation.

Ans : a) Transformer substation, b) Converting substation, c) Frequency substation, d) Switching substation, e) Power factor correction substation, f) Industrial substation.

Ans : A substation, in which the voltage is either stepped up or stepped down by means of a transformer, is called a transformer substation.

Ans : A substation, where a.c. energy is converted into d.c. energy, is called converting substation.

Ans : A substation, in which the frequency is changed from one value to the another value with the help of frequency converter, is known as frequency substation.

Ans : A substation, in which simple switching operation of power lines is performed without the voltage level, is called as switching substation.

Ans : A substation located at the receiving end of the transmission lines, in which power factor correction is performed by using generally synchronous condensers, is called as power factor-correction substation.

Ans : A substation, from which the power is supplied to individual industrial concern, is known as industrial substation.

Ans : a) Step up substation, b) Primary grid substation, c) Secondary substation, d)Distribution substation, e) Bulk supply and industrial substation, f) Mining substation g) Mobile substation.

Ans : The step up substation is associated with the power station where the generation voltage is stepped up to the primary transmission voltage.

Ans : The substation created at suitable load centres along the primary transmission line, in which the primary transmission voltage is stepped down to a number of suitable secondary transmission voltages, is called primary grid substation.

Ans : The substation created at actual load point along the secondary transmission lines, where the voltage, is further stepped down to sub-transmission or primary distribution voltage, is called secondary substation.

Ans : The substation, where the sub transmission voltage or the primary distribution voltage is stepped done to supply voltage for feeding the consumers through a network of distribution lines, is called distribution substation.

Ans : The distribution substation created for an individual bulk supply consumer or an industrial consumer of large or medium supply ground is known as bulk supply and industrial substation.

Ans : The mining substation is a specially is a specially designed substation created for the purpose of mining installation which provides extra precaution for safety in the operation of electric supply.

Ans : The substation, which is created for temporary requirements of mainly construction purposes, is called mobile substation.

Ans : a) High voltage isolator, b) High voltage switchgear, c) Main busbars, d) Transformer, e) Low voltage switchgear and busbars, f) Cables, g) Fuses, h) Auxiliary equipments, i) Instrument transformers, j) Measuring instruments, k) Indicating instruments, l) Protective, m) Control cable & circuits etc.

1. Interview Question of Thermal Power Station
2. Interview Question of hydro electric power station
3. Interview Question of nuclear power station
4. Interview Question of gas turbine plant and Magneto hydro dynamic generator ( M.D.G ) plant
5. Interview Question of Power Station
6. Interview Question of Substation
7. Interview Questions on earthing of Substation
8. Interview Question of Bus Bar system of Substation
9. Interview Question of Isolator
10. Interview Question of circuit breaker and Switchgear
11. Interview Question of circuit breaker