II B.Tech II Semester II Mid Examinations, March-April 2011 Max Marks: 10
POWER SYSTEMS-I Time: 1 hour
Answer any TWO Questions (Electrical & Electronic Engineering) All Questions carry equal marks
1. A synchronous motor improves the pf of a load from 0.7 to 0.9 lagging. The losses and other mechanical load on it amount to (250 +200) KW, while the load for which power factor is considered is 1,500 KW. Find out the input to the synchronous motor in KVA and its power factor.
2. Classify substations by considering the constructional features?
3. A factory has a maximum demand of 500 KW, the load factor being 60 % during working hours.
The following two tariff's are available:
( i ) Rs 8 per KW of maximum demand plus 3 paisa per KWh ( ii ) A flat rate of Rs 0.1 per KWh.
Determine the working hours per week above which tariff will be cheaper.
Determine the working hours per week above which tariff will be cheaper.
4. Compute the generation cost per KWh from the following data: Installed capacity = 200MW;
capital cost = Rs 3000 per KW; Interest and depreciation = 12%; Fuel consumption= 0.9 Kg/KWh;
Fuel cost = Rs 70 per 1000Kg; other operating costs = 30% of fuel costs; load factor = 80%; peak load=170 MW.
II B.Tech II Semester II Mid Examinations, March-April 2011 Max Marks: 10
POWER SYSTEMS-I Time: 1 hour
Answer any TWO Questions (Electrical & Electronic Engineering) All Questions carry equal marks
- The load connected to a station is 100 MW and the demand factor of the consumers is 1.25. Estimate the capacity of the generating station when load factor is 60%, capacity factor is 50%, diversity factor of distribution is 1.33 and that of transmission is 1.5. Take the efficiency of transmission and distribution as 90%.
- A consumer is offered power at Rs 50 per annum per KVA of maximum demand plus 5 paise per unit. He proposes to install a motor to carry his estimated maximum demand of 300 b.h.p. The motor available has a power factor of 0.83 at full load. How many units will be required at 30 % load factor and what will be the annual bill? The motor efficiency is 90%
- A consumer has an average demand of 400 KW at a p.f of 0.8 laging and annual load factor of 50%. The tariff is Rs 50 per KVA of maximum demand per annum plus 5 paise per KWh. If the power factor is improved to 0.95 lagging by installing phase advancing equipment, calculate the capacity of phase advancing equipment.
- Write a short notes on the construction aspects of a Gas Insulated Substation.
II B.Tech II Semester II Mid Examinations, March-April 2011 Max Marks: 10
POWER SYSTEMS-I Time: 1 hour
Answer any TWO Questions (Electrical & Electronic Engineering) All Questions carry equal marks
- Draw the layout & schematic connection of a pole mounted substation
- A synchronous motor improves the pf of a load from 0.7 to 0.9 lagging. The losses and other mechanical load on it amount to (250 +200) KW, while the load for which power factor is considered is 1,500 KW. Find out the input to the synchronous motor in KVA and its power factor.
3. A factory has a maximum demand of 500 KW, the load factor being 60 % during
working hours. TH e following two tariffs’ are available:
( i ) Rs 8 per KW of maximum demand plus 3 paisa per KWh
( ii ) A flat rate of Rs 0.1 per KWh.
Determine the working hours per week above which tariff ( i ) will be cheaper.
4. Compute the generation cost per KWh from the following data: Installed capacity = 200MW;
capital cost = Rs 3000 per KW; Interest and depreciation = 12%; Fuel consumption= 0.9 Kg/KWh;
Fuel cost = Rs 70 per 1000Kg; other operating costs = 30% of fuel costs; load factor = 80%; peak load=170 MW.
II B.Tech II Semester II Mid Examinations, March-April 2011 Max Marks: 10
POWER SYSTEMS-I Time: 1 hour
Answer any TWO Questions (Electrical & Electronic Engineering) All Questions carry equal marks
- The load connected to a station is 100 MW and the demand factor of the consumers is 1.25. Estimate the capacity of the generating station when load factor is 60%, capacity factor is 50%, diversity factor of distribution is 1.33 and that of transmission is 1.5. Take the efficiency of transmission and distribution as 90%.
- A consumer is offered power at Rs 50 per annum per KVA of maximum demand plus 5 paise per unit. He proposes to install a motor to carry his estimated maximum demand of 300 b.h.p. The motor available has a power factor of 0.83 at full load. How many units will be required at 30 % load factor and what will be the annual bill? The motor efficiency is 90%
. 3. a) Write a short notes on the construction aspects of a Gas Insulated Substation.
b) Write short notes on the advantages of a Gas Insulated Substations.
4. A consumer has an average demand of 400 KW at a p.f. of 0.8 lagging and annual load factor of 50%. The tariff is
Rs 50 per KVA of maximum demand per annum plus 5 paisa per KWh. If the power factor is improved to 0.95
lagging by installing phase advancing equipment, calculate the capacity of phase advancing equipment.
lagging by installing phase advancing equipment, calculate the capacity of phase advancing equipment.
No comments:
Post a Comment