The ideal power factor is unity, or one. Anything less than one means that extra power is required to achieve the actual task at hand. All current flow causes losses both in the supply and distribution system. A load with a power factor of 1.0 results in the most efficient loading of the supply.

All phasors are drawn referenced to the horizontal zero axis. Phasor diagrams can be drawn to represent more than two sinusoids. They can be either voltage, current or some other alternating quantity but the frequency of all of them must be the same. All phasors are drawn rotating in an anticlockwise direction.

Phasor analysis is a technique to find the steady-state response when the system input is a sinusoid. That is, phasor analysis is sinusoidal analysis. Phasor analysis is a powerful technique with which to find the steady-state portion of the complete response.

The power factor in a single-phase circuit (or balanced three-phase circuit) can be measured with the wattmeter-ammeter-voltmeter method, where the power in watts is divided by the product of measured voltage and current. The power factor of a balanced polyphase circuit is the same as that of any phase.

It is found by multiplying (kVA = V x A). The result is expressed as kVA units. PF expresses the ratio of true power used in a circuit to the apparent power delivered to the circuit. A 96% power factor demonstrates more efficiency than a 75% power factor.

Causes of low Power Factor

• Single phase and three phase induction Motors(Usually, Induction motor works.
• Varying Load in Power System(As we know that load on power system is varying.
• Industrial heating furnaces.
• Electrical discharge lamps (High intensity discharge lighting) Arc lamps (operate.
• Transformers.
• Harmonic Currents.

Power factor correction (PFC) aims to improve power factor, and therefore power quality. It reduces the load on the electrical distribution system, increases energy efficiency and reduces electricity costs. It also decreases the likelihood of instability and failure of equipment.

Though reactive power is needed to run many electrical devices, it can cause harmful effects on your appliances and other motorized loads, as well as your electrical infrastructure.

If reactive power flows over the transmission line, there will be a voltage drop. The effect of reactive power flow on transmission efficiency and power factor has been presented. Shunt-capacitive arrangement reduced the total active power loss while series- capacitive arrangement had no effect on it.