Reactive Power and Active Power flow in Power System

Active Power:

The power that is generated in the power system which is utilised in useful work (running the motor, lighting and heating energy)

Reactive Power:

Reactive power is the power which will not do any useful work in the power system but helps the active power to flow. Without Reactive Power active power will not able to flow in the system.

Different Power Flow In Power System:

Active power in the power system depends on the power angle, means active power will flow in power system from bus having leading voltage power angle to lagging voltage power angle busbar. On the other hand, reactive power flow from the high voltage bus to low voltage bus in the power system, under this condition reactive power generated in the line (normally generated by alternator or shunt capacitance) is more compared to the reactive power absorbed (normally sink for reactive power will be series inductance) at the receiving end.

• P (active power ) and delta (power angle) are closely coupled
• Q (Reactive Power) and V (magnitude of the voltage) are closely coupled

Hence it is understood that for the flow of reactive power from one point to other in power system difference in the voltage should exist. Active power will flow in power system from leading power angle to lagging power angle even the voltage at receiving end is higher compared to sending end (still active power flows).