11. The A, B, C, D constants of a 220 kV line are:
    A = D = 0.94 ∠1°,
    B = 130 ∠73°,
    C = 0.001 ∠90°
    If sending end voltage of the line for a given load delivered at nominal voltage is 240 kV, then % voltage regulation of the line is

1. 1. 5

   
   
   

   2. 9

   
   
   

   3. 16

   
   
   

   4. 21

   
   
   

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1. View Hint View Answer Discuss in Forum

   Voltage at sending-end,
   V_s = AV_R + BI_R
   at no-load,
   I_R = 0
   and
   

   VRO =	Vs	=	240
   	A		0.94∠1°

   
   = 255.32 Volts
   

   % voltage regulation =	VRO - VRL	× 100
   	VRL

   
   Where V_RL is the full-load voltage at receiving-end
   

   =	255032 - 220	× 100 = 16%
   	220

   
   

   Correct Option: C

   Voltage at sending-end,
   V_s = AV_R + BI_R
   at no-load,
   I_R = 0
   and
   

   VRO =	Vs	=	240
   	A		0.94∠1°

   
   = 255.32 Volts
   

   % voltage regulation =	VRO - VRL	× 100
   	VRL

   
   Where V_RL is the full-load voltage at receiving-end
   

   =	255032 - 220	× 100 = 16%
   	220

   
   

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12. An HVDC link consists of rectifier, inverter transmission line and other equipments. Which one of the following is true for this link?

1. 1. The transmission line produces/supplies reactive power

   
   
   

   2. The rectifier consumes reactive power and the inverter supplies reactive power from/to the respective connected AC systems

   
   
   

   3. Rectifier supplies reactive power and the inverted consumes reactive power to/from the respective connected AC systems

   
   
   

   4. Both the converters (rectifier and inverter) consume reactive power from the respective connected AC systems

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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13. In a biased differential relay, the bias is defined as a ratio of

1. 1. number of turns of restraining and operating coil

   
   
   

   2. operating coil current and restraining coil current

   
   
   

   3. fault current and operating coil current

   
   
   

   4. fault current and restraining coil current

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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