A large portion of electrical power generated by utility plants is supplied to factories . much of the equipment in an industrial plantconsists of motors and transformars.
A large portion of electrical power generated by utility plants is supplied to factories . much of the equipment in an industrial plant consists of motors and transformers.
Some of the current from the feeder line provides true power , which is consumed by electrical energy being converted to heat energy and mechanical energy. True power performs work , and its consumption is from;
A large portion of electrical power generated by utiluty plants is supplied to factories . much of the equipment in an industrial plant consist of motors and transformers.
Some of the current from the feederline provides true power , which is consumed by eectrical energy being converted to heat energy and mechanical energy. True power performs work ,and its consumption is form:
· The mechanical energy of the motor required to physically turn the load.
· The mechanical energy required to overcome the bearing friction and windage (actual air resistance to the rotor turning.)
· Heat dissipation from the resistance in the wire, eddy currents and hysterisis loses in the iron cores
The remainder of the current from the feeder line is used to produce magnatic fields that explained around the coiles. When these fields collaps during each AC a;ternation, they induce a voltage back into the coils , which causes current to be returned back through the feeder line to the generator , this type of power , called reactive power , called does not perform any work
The combination of true power and reactive power sent to the factory is called appearnt power . because moter coils are inductive . the reactive power and the true power that pass through the feeder line are not on phase.
Therefore, apperent power is the phasor sum true and reactive power.
The ratio of true power to apperent power is reffered to as the power factor , abbrevaiated (pf) . it is expressed by the following formula
The power factor is an indication of the efficency of a circuit , which refers to how much energy supplied by the source performs work, an efficent circuit is one that uses most of the energy from the feeder line to perform work and consumes a high amount of true power . when all of the energy form the source is used , the power factor is equal to 1.
An efficent circuit is one that uses very little energy to performs work an example is when the motors are driving light loads that don’t require much physicalpower to turn . in this situation , more of the line current is used to produce the reactive power , which creates the magnatic field around the coils , then the true power that performs work . if allof the current formthe sorce is used to create maganatic fields and none of it performs work , the power factor is equal to 0 .
A common power factor for a factory is in the range of 0.6
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