Reactive power:
1) Almost all is power transported or consumed in alternating current (AC) networks. AC systems supply or consume two kind of power real power and reactive power.
2)Real power accomplishes useful work while reactive power supports the voltage that must be controlled for system reliability.
3)For AC systems voltage and current pulsate at the system frequency. Although AC voltage and current pulsate at same frequency, they peak a different time power is the algebraic product of voltage and current.
4) Real power is the average of power over cycle and measured by volt-amperes Or watt
5) The portion of power with zero average value is called reactive power and is measured in volt-ampere reactive or var.
6) The total power is called the apparent power (symbolized by the capital letter S) and measured by volt-amperes or VA.
7) To describe the reactive power, imagine a person on trampoline, the person real power goes into moving horizontally across trampoline as it bounces, the effort the person expend to keep standing (represent reactive power ) during bouncing result no net forward motion (represent real power P), but it’s necessary to walk on trampoline.
8) The motion from trampoline always perpendicular to the direction the person is walking So that the direction between P and Q is 90 degree out of phase.
