WHY RAISE THE POWER FACTOR? (Electric Motor)

4.3
A low power factor causes poor system efficiency. The total apparent power must be supplied by the electric utility. With a low power factor, or a high-kilovar component, additional generating losses occur throughout the system. Figures 4.3 and 4.4 illustrate the effect of the power factor on generator and transformer capacity. To discourage low-power factor loads, most utilities impose some form of penalty or charge in their electric power rate structure for a low power factor.
When the power factor is improved by installing power capacitors or synchronous motors, several savings are made:
1. A high power factor eliminates the utility penalty charge. This charge may be a separate charge for a low power factor or an adjustment to the kilowatt demand charge.
Power factor effect on generator capacity.
FIGURE 4.3 Power factor effect on generator capacity.
2. A high power factor reduces the load on transformers and distribution equipment.
3. A high power factor decreases the I2R losses in transformers, distribution cable, and other equipment, resulting in a direct saving of kilowatt-hour power consumption.
4. A high power factor helps stabilize the system voltage.
Power factor effect on transformer capacity.
FIGURE 4.4 Power factor effect on transformer capacity.


Next post:

Previous post: