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Answer :

When a transmission line is energized, the wave that propagates on it is current wave and voltage wave.

Related questions

Last Answer : When a wave propagates on a transmission line, it suffers reflection several times at sending and other end.

Description : Transmission efficiency of a transmission line increases with the

Last Answer : Transmission efficiency of a transmission line increases with the increase in power factor and voltage

Last Answer : Reactance relay is preferred for phase fault on short transmission line.

Last Answer : The interaction between a transmission line and communication line is minimized by transposing transmission as well as communication lines, increasing the height of the transmission line tower, increasing the distance between the two lines.

Last Answer : A transmission line is protected by distance protection, time graded and current graded overcurrent protection.

Description : State the limitations of EHVAC transmission line. 

Last Answer : Following are the Limitations of EHVAC Transmission:   1. Insulation cost increases as voltage increases 2. Skin effect is more 3. Proximity effect is more. 4. Corona loss increases. 5. Radio ... 18. EHVAC is economical only for bulk amount of power is to be transmitted over long distance. 

Description : State line parameters of transmission line. 

Last Answer : Following are the of Line parameters of transmission line:  1. Resistance  2. Inductance  3. Capacitance

Description : State the impact of inductance and resistance on transmission line performance

Last Answer : Impact of inductance on transmission line: 1) It causes IXL drop in transmission line which affects regulation. 2) It is the only parameter which decides power transmission capacity of line i. ... is very small, it causes losses, temperature rise& poor voltage regulation so it cannot be neglected

Description : effect of inductance and capacitance on performance of transmission line.

Last Answer : Following are the effect on performance of transmission line:  1. Due to inductance (L) voltage drop in transmission line produces.  2. Capacitor (C) draws charging current ... , transmission line efficiency, voltage regulation & also power factor of transmission line gets affected. 

Description : While calculating performance of medium transmission line, what assumptions are made in case of (i) Nominal 'T' Method (ii) Nominal 'TT' Method. 

Last Answer : (i) Assumptions are made in case of Nominal 'T' Method:  a. It is assume that line capacitance is connected at center of transmission line. b. It is assume that half ... assumed that transmission line resistance & reactance per phase is connected in between two half transmission line capacitance 

Description : HVDC transmission line in India: 

Last Answer : HVDC transmission line in India:  S.N .  From To  Voltage 1 Rihand (U.P) (from 1990) Dadri +- 500 KV (bipolar) 2 Talcher- is the biggest ... (Chandrapur) Western Region  140KV   8 Connecting Southern region(Vizag- Gajuwaka) Eastern Region 140KV 

Description : effect of line parameter on performance of transmission line. 

Last Answer : Following are the effect of line parameter on performance of transmission line:  1. Due to resistance (R), voltage drop in transmission line & copper losses in transmission line ... transmission line efficiency, voltage regulation & also power factor of transmission line gets affected. 

Description : Why is transmission line 11kV, 33kV 66kV Not Is 10kV, 20kV, 30kV ?

Last Answer : 10kv plus to compensate losses in olden days 1kv were added and transmitted. Since all equipment used for transmission have a multiple of 11 from olden days, still that is being followed even though the losses are ... voltages, multiples of 11 is eazy for winding ratios.. i.e. 11kv to 33kv is 1:3.

Description : A 50Ω transmission line is terminated in an impedance of 20-j50. What will be the reflection coefficient? A) 0.69 B) 1.69 C) 6.9 D) 16.9 

Last Answer : A 50Ω transmission line is terminated in an impedance of 20-j50. What will be the reflection coefficient? A) 0.69 B) 1.69 C) 6.9 D) 16.9 

Description : Stability of a transmission line can be increased by

Last Answer : Stability of a transmission line can be increased by Shunt capacitor, Series capacitor

Description : The sag of a transmission line is least affected by (A) Self weight of the conductor. (B) Temperature of the surrounding air. (C) Current through the conductor. (D) Ice deposited on the conductor.

Last Answer : The sag of a transmission line is least affected by Current through the conductor.

Description : In a transmission line if booster transformers are to be used, preferred location will be  (A) At the receiving end (B) At the sending end (C) At the intermediate point (D) Anywhere in the line 

Last Answer : In a transmission line if booster transformers are to be used, preferred location will be At the intermediate point

Description : A transmission line has 1 P.0 impedance on a base of 11 KV, 100 MVA. On a base of 55 KV. it will have a P.0 impedance of

Last Answer : A transmission line has 1 P.0 impedance on a base of 11 KV, 100 MVA. On a base of 55 KV. it will have a P.0 impedance of 0.02 P.U

Description : For a short transmission line with r/x ratio of is 1.0, the regulation will be zero when the load power factor is

Last Answer : For a short transmission line with r/x ratio of is 1.0, the regulation will be zero when the load power factor is 0.707 lead

Description : A transmission line of 200 km has a certain A, B, C and D parameters. If the length is reduced to 60 km

Last Answer : A transmission line of 200 km has a certain A, B, C and D parameters. If the length is reduced to 60 km A increases, B decreases

Description : Series capacitive compensation in EHV transmission line is used to

Last Answer : To maintain voltage stability 

Description : The sending end and receiving end voltages of a three-phase transmission line are 10 kV/ph and 9.5 kV/ph, respectively. If the resistance drop is 150 V/ph and receiving end power factor is 0.8, the sending end power factor is (A) 0.745 lagging (B) 0.775 lagging (C) 0.8 lagging (D) 0.85 lagging

Last Answer : Vscos¢s-Vrcos¢r=IR

Description : what is mean by medium transmission line ?

Last Answer : The transmission line which have length between 80 km to 250 km is known as medium transmission line.

Description : what is mean by short transmission line ?

Last Answer : The transmission lines which have length less than 80 km is known as short transmission lines.

Description : what is mean by long transmission line ?

Last Answer : The transmission line which have length more than 250 km are known as long transmission lines.

Description : When a transmission line is energized, the wave that propagates on it is (a) current wave only (b) voltage wave only (c) both (a) and (b) (d) power factor wave only

Last Answer : (c) both (a) and (b)

Last Answer : Wave trap is used to trap waves of higher frequencies entering generator or transformer units.

Description : lf a travelling-wave travelling along a loss-less overhead line does not result in any reflection after it has reached the far end, then the far end of the line is

Last Answer : lf a travelling-wave travelling along a loss-less overhead line does not result in any reflection after it has reached the far end, then the far end of the line is terminated into a resistance equal to surge impedance of the line

Description : The surge impedance for over head line is taken as  (1) 10-20 ohms (2) 50-60 ohms (3) 100-200 ohms (4) 1000-2000 ohms

Last Answer : The surge impedance for over head line is taken as 100-200 ohms

Description : A lightening arrester connected between the line and earth in a power system  (1) protects the terminal equipment against travelling surges (2) protects the transmission line against direct ... suppresses high frequency oscillations in the line (4) reflects back the travelling wave approaching it

Last Answer : A lightening arrester connected between the line and earth in a power system protects the terminal equipment against travelling surges

Description : The reactive power transfer over a line mainly depends on

Last Answer : The reactive power transfer over a line mainly depends on lVsl- lVRl

Last Answer : The inductive interference between power and communication line can be minimized by transposition of the power line, transposition of the communication line.

Last Answer : Impedance relays are used for phase faults on long line.

Description : A circuit is disconnected by isolators when (a) line is energized (b) there is no current in the line (c) line is on full load (d) circuit breaker is not open

Last Answer : (b) there is no current in the line

Description : The voltage of transmission can be regulated by  (A) Use of tap changing transformers (B) Switching in shunt capacitors at the receiving end during heavy loads (C) Use of capacitors to neutralize the effect of series reactance (D) Any of the above methods

Last Answer : The voltage of transmission can be regulated by  (A) Use of tap changing transformers (B) Switching in shunt capacitors at the receiving end during heavy loads (C) Use of capacitors to neutralize the effect of series reactance (D) Any of the above methods

Last Answer : Ungrounded neutral transmission system is not recommended because of system insulation being overstressed due to over voltages, insulation overstress may lead to failure and subsequent phase to phase faults, being inadequately protected against ground fault.

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Description : Draw single phase full wave mid-point converter for inductive load. Draw input and output waveforms for it. 

Last Answer : Circuit Diagram: Waveforms:

Description : operation of half wave rectifier type AC Voltmeter.

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Description : State the concept of continuous wave RADAR. Sketch its block diagram. State its any two applications.

Last Answer : Concept- Transmission is continuous here, the circulator is used to provide isolation between the transmitter and the receiver. Since transmission is continuous, it would be pointless to use a ... It is used to measurement of relative velocity to distinguish moving target from stationary objects 

Description : State advantages and disadvantages of continuous wave Radar

Last Answer : Advantages continuous wave RADAR : 1.Single frequency transmission and hence narrow receiver bandwidth 2.Duty cycle is unity, so mean power can be as high as transmitters will permits. 3.Ability ... required for receiver and transmitter. 3.Cannot detect targets crossing its beam at right angles.

Description : Justify electromagnetic wave is said to be transverse wave. 

Last Answer : Transverse electromagnetic wave:- The electromagnetic waves are oscillations which propagate through free space. In electromagnetic waves the direction of electric field, magnetic field & propagation are ... electric field vector with respect to the surface (i.e. looking at the horizon) 

Description : Define : i) Average value ii) RMS value of an AC Wave.

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Description : Give the operation of single phase full wave bridge controlled converter with RL load with a neat diagram. Also draw its waveform.

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Description : Draw a neat diagram of 1Ф half wave controlled converter with RL load. Give its operation.

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Description : Instantaneous value of a sine wave voltage

Last Answer : Instantaneous value of a sine wave voltage

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