Disadvantage of Low Power
Disadvantage of Low Power and Causes of low power factor , In this post you will know about what is causes and disadvantages of low power factor in electrical engineering .
Power Factor
The power factor of a circuit can be defined as one of the following way
Disadvantage of Low Power Factor |
1. The cosine of angle between Voltage (V)and current (I) is known as power factor
2. it is the ratio of Resistance and Impedance
Power factor=R/Z= Resistance\Impedance
3.It is the ratio of true power and Apparent power
Power Factor = True Power/Apparent Power
For example , in a resistor , the current and voltage are in phase . Therefore, power factor of a pure resistive circuit is cos 0=1. Similarly , phase difference between voltage and current in a pure inductive or capacitive circuit is 90 degree.Hence power factor of pure L or c circuit is zero. This is the reason that power consumed by pure L or c is zero.
Cause of low power factor
The following are the main causes of low power factor
- Transformers , generator and chocks are inductive loads which causes the current to lag behind the voltage. i.e., they operate at a lagging power factor . However , at normal loads , the magnetising current does not effect and lowers the power factor.
- The motors which are used in industries are mostly induction motors having inductive loads, which have low power factor . Normally the power factor of induction motors varies from 0.8 to 0.85
- Arc laps , heating furnaces ( Induction and are furnaces also operate at low power factor (lagging)
What are the disadvantage of low power Factor
The higher current result in the following disadvantages
- Large conductor size : To transmit or distribute a fix amount of power at a fixed voltage at low power factor , the conductor will have to carry larger current which will necessitate a large conductor size.
- Large Copper Losses : Due to more current carried by the conductor , large copper losses
- Poor Voltage Regulation : Due to power factor and increased currents, the voltage drop in transformers , alternators and transmission/ distribution lines is higher which results in poor voltage regulation
- Large KVA rating of the equipment : the output power of electrical machines e.g. alternators and transformers is always rated in apparent power
- Poor Efficiency : Due to the low power factor efficiency of all our system is decreased .
I think this information about disadvantage of low power and causes of low power factor will helpful for you . if you have more question then Comment us your question below
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