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Power System Interview Question Part 1

Q. What is a load duration curve?

A. It is the plot of load in Kilowatts versus time duration for which it occurs in the descending order of magnitude, irrespective of time of occurrence.

Q. What is load factor?

A. The ratio of average load to the maximum demand during a given period is known as load factor.

Q. What is average load?

A. The average of loads occurring on the power station in a given period is known as average load or average demand.

Q. What is maximum demand?

A. Maximum demand is the greatest demand of load on power station during a given period of time.

Q. What is demand factor?

A. Demand factor is the ratio of maximum demand on the power station to its connected load.

Q. What is meant by connected load?

A. Connected load is the sum of continuous ratings of all the equipment connected to the supply system.

Q. What is diversity factor?

A. Diversity factor is the ratio of sum of individual maximum demands to the simultaneous maximum demand on the power station.

Q. What is coincidence factor?

A. It is the reciprocal of diversity factor.

Q. What is plant capacity factor?

A. it is defined as the ratio of average demand on the station to the maximum installed capacity.

Q. What is cold reserve and hot reserve?

A. Cold reserve is the reserve generating capacity which is available for service but is not in operation. Hot reserve is the reserve generating capacity which is in operation but not in service.

Q. What is meant by a spinning reserve?

A. Spinning reserve is the generating capacity which is connected to bus and is ready to take load.

Q. What is base load and peak load?

A. The unvarying load which occurs almost the whole day on the station is known as base load. The various peak demands of load over and above the base load of the station is known as peak load.
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