Answer / m.mousa

We could define the reactive power if we how it generates
as follow.
All inductive (i.e. electromagnetic) machines and devices
that operate on AC systems convert electrical energy from
the power system generators into mechanical work and heat.
This energy is measured by kWh meters, and is referred to
as “active” or “wattful” energy. In order to perform this
conversion, magnetic fields have to be established in the
machines, and these fields are associated with another form
of energy to be supplied from the power system, known
as “reactive” or “wattless” energy.

Answer / saleem pasha

reactive power will come in picture when ever the voltage
and current are not in phase in AC CIRCUITS,
POWER THAT CONTINOUSLY BOUNCE BACK AND FORTH BETWEEN SOURCE
AND LOAD IS KNOWN AS REACTIVE POWER , AND IS MEASURED IN VAR.
IN CASE OF POWER PLANT, SUPPLYING POWER TO INDUCTIVE LOAD
LIKE INDUCTION MOTOR WHICH REQUIRE REACTIVE POWER TO PRODUCE
MAGNETIC FIELD FOR THEIR OPERATION, IF AT ANY TIME THE MOTOR
RECEIVE LESS REACTIVE POWER FROM SOURCE THEN VOLTAGE WILL
SAGDOWN AND IT IS NOT POSSIBLE TO PUSH THE POWER DEMANDED
BY THE MOTOR , THEN IT BECOME NECESSARY TO SUPPLY OR
GENERATE REACTIVE POWER WITH THE HELP OF CAPACITOR BANK/OVER
EXCITED SYNCH MOTOR/THYRISTER CONTROL CAPACITIVE
INDUCTOR/VOLTAGE SOURCE INVERTER, IN THIS WAY WE CAN CONTROL
REACTIVE POWER.

Answer / prabhat kumar sinha, banswara.

The Power taken by pure reactance in a circuit is called
reactive Power. The Unit of reactive power is VAR.
Reactive Power = Apparent power x value of Sin angle of
between voltage & current = VI Sin phi.
It can controled by the increase the angle of Sin, it means
close to Sin phi = Sin 90° = 1.

Answer / vidhya

The power which is essential to drive a system but returned
back to the same system itself after used.With the help of
static var compensators we can effectively control and
compensate the reactive power.

Answer / macharia

reactive power is wattless power (without energy flow)
caused by reactive loads: capacitive and inductive
(induction motors, solenoid valves, transformers) loads. It
is measured in var - volt-amps-reactive. capacitors release
while inductors use the reactive power. reactive power
causes increase in current in transmission lines and hence
large voltage drop. this may require oversizing of
transmission lines.

capacitors can be installed to cancel the reactive power
from inductance of motors.

Answer / mohammad

the reactive power is the power which is consumed in
capacitive(absorbtin) or inductive (production) loads
and controled by changing the reactance of the loads

Answer / a. al saqqa

THE REACTIVE POWER IS THE PART OF POWER THAT WILL BE
NECESSARY FOR POWER CONVERSION PROCESS IN ALL EQUIBMENT
WICH NEED MAGNETIC FIELD TO OPERATE
THIS PART OF POWER IS MEASURED IN VAR WHICH MEANS VOLT-
AMPERE REACTIVE
IN POWER PLANETS WE CAN CONTROL THE REACTIVE POWER BY
CONTROLLING THE EXCITATION OF THE SYNCH. GENERATORS AND
ADDITIONALLY BY USING ONE OF POWER FACTOR IMPROVEMENT
METHODS AT LOAD CENTER
AS WELL AS THE REACTIVE POWER CONTROL IS POOR THE POWER
FACTOR IS MORE LESS THAN UNITY AND CONSIDERABLE VOLTAGE
DORP WILL BE EXIST IN THE NETWORK
THIS CAN BE OVERCOMED IN POWER PLANT OR POWER GENERATING
STATION BY CORRECT AND CONTINEOUS CONTROL OF GENERATOR
FIELD CURRENT

Answer / ranjeet

reactive power is wattless power and it is control by using
capacitive element[capacitor]

Answer / r. parthiban

The partial portion of apparent power due to the stored energy (In Inductance) in the transmission line, return back to the source in each cycle is known as Reactive Power.
For Purely resistive loads Reactive Power is zero because sin0=0 and Active power only presents.
Whenever there is phase angle difference there will be a reactive power.
To Compensate this reactive power to get full active power, we use FACTS device (All the devices includes Capacitor) which is known as Reactive Power Control

Answer / e. elmalt

the reactive power is the power that stored in capacitors
_that is -ve value_ or reactor(coil) _that is + ve value _
we can controlled it by using shunt cap or serise reactor

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1 Answers  

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2 Answers  

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3 Answers  

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6 Answers  

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0 Answers  

mention the earthing system as per BIS?

1 Answers  

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1 Answers  

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1 Answers