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What is the active power consumed by pure capacitive reactance?
Wiki User
∙ 12y ago
There is no 'active' power in a purely capacitive load. Active power is the result of the supply voltage multiplied by the in-phase component of the load current. In a purely capacitive load, the load current leads the supply voltage by 90 degrees and, so, there is no in-phase component and, hence, no active power.
Wiki User
∙ 12y ago
Wiki User
∙ 12y agoPower = Watts = Volts x Amps x Power Factor.
Power Factor is 1 for resistive load and decreases with inductive loads. Power Factor is essentially related to the difference in phase between the voltage and current waveforms. The bigger the phase difference, the smaller the power factor. If they are 180 degrees out of phase no power is delivered.
AnswerA purely-inductive load has no resistance. Therefore, the load current lags the suppy voltage by 90 degrees -giving a power factor of 0.
Since P = V I x power factor, it is clear that no active power is supplied.
(Further to the original answer, the current through a pure inductance cannot be 180 degrees out of phase with the supply voltage!)
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What load impedance Z will result in maximum power transfer from an electric source with an internal impedance of r?
For maximum power transfer, source resistance should match load resistance and source reactance should match load reactance with the opposite sign (so if the load is capacitive, the source should be inductive).
What is wattless capacitive power?
I believe you're referring to reactive power. Reactive power is present any time the voltage and current are AC signals and not in phase. Some current simply charges and discharges the load reactance, and therefore does not deliver real power to the load.
When does power consumed in an ac circuit becomes zero?
The power consumed in an AC circuit becomes zero when the voltage and current are in phase with each other. This means that the voltage and current waveforms reach their maximum and minimum values at the same time, resulting in a power factor of 1. In this case, the power consumed by the circuit is purely reactive and does not contribute to any real power dissipation.
Which power factor is advantage lagging or leading and why?
A lagging power factor is caused by inductive reactance, which is composed of resistance and inductance -- and the resistance component lowers the supply volts. A leading power factor provides capacitive reactance that actually helps improve source voltage -- this helps motor loads run cooler.
What is percentage reactance of a power system?
If the load on an AC system is purely resistive, then the voltage and current waveforms will be in phase. A desirable state. When the load has some reactance, then these two parts of the power signal will not be in phase; and this results in an inferior power generation, in which some of the work needed to generate the signal is not available as real work at the terminus. This undesirable condition occurs with both inductive loads such as electric motors, and capacitive loads, such as fluorescent lighting. This may be corrected for in real-life systems by employing 'power factor' correcting equipment. One common device is the 'rotary capacitor' - in reality, a rotating transformer in which the phase is controlled as to make it appear as a capacitor, not as an inductor. Ordinary transformers transfer the reactance of their load, with a small percentage of genuine reactance due to hysteresis losses in the core of the transformer.
What are the three types of opposition to current flow that impedance represents?
There is pure resistance, inductive reactance, and capacitive reactance.
How is the power factor improved in an AC system?
by adding the opposite type of reactance. as motors are a common industrial load and their reactance is inductive, add capacitive reactance.
What types of loads have a leading power factor?
Capacitive loads have a leading power factor. Current leads voltage when there is capacitive reactance. (The opposite is inductive, which is lagging.)
What is the power dissipated by a reactive load?
No power is dissipated by a load composed exclusively of either capacitive or inductive reactance.
What effect do var's have on the power factor of the circuit?
VAr is reactive power, caused by either inductive or capacitive loads. The ideal power factor to have is 1, anything less than that is a loss on the network. The effect of VArs on the circuit though depends. If you have a load that is mainly inductive, then adding more inductive reactance will lower the power factor. However, if you introduce capacitive reactance this will increase the power factor, and the opposite is true if its a mainly capacitive circuit. So VArs will either increase or decrease the power factor depending on the load of the circuit. The ideal situation is to balance inductive reactance with capacitive reactance so they in effect cancel each other out and power factor is 1.
What is the active power consumed by pure inductive reactance?
The active power of an inductor is zero. As we know, the active power is the result of product of supply voltage and in-phase component of load current. But the load current in pure inductive load lags supply voltage by 90 degrees. So there is no component of load current that is in-phase with the supply voltage. Therefore, the active power in inductive reactance is zero.
Does the power factor in three phase system depend on the phase sequence?
No. It depends on the inductive and capacitive reactance of the load.
Is it really possible to avoid reactive power in electrical circuit?
yesAnswerNo, but you can counter its effects. For example, if your load is inductive, then you can counter the effects of its inductive reactance by introducing capacitors with equal capacitive reactance.
What is current voltage power and resistance?
current - movement of electrical chargesvoltage - electrical force/pressurepower - work doneresistance - opposition to currentinductive reactance - opposition to changes in currentcapacitive reactance - opposition to changes in voltagetotal impedance - vector sum of resistance, inductive reactance, and capacitive reactanceetc.
What happen to the voltage regulation and transmission efficiency when power factor of receiving end is increased?
When the power factor is 1, that is neither capacitive or inductive, the load does not have reactance that impedes current flow. Power companies like that.
In order to reduce inductive reactance what devices are normally placed on transmission or distribution lines?
== == Add a capacitor or a synchronous motor or a phase advancer to the transmission line so that it can nullify the effect of inductive reactance since the above elements gives capacitive reactance. Doing this also improves the power factor.
Which watt meter used for capacitive loads?
Wattmeters are not used for loads which are purely capacitive or inductive, because no watts are consumed and no energy is consumed by the customer. But amps must still be supplied by the power company to supply the customer's capacitive or inductive load and the result is measured in volt-amps reactive (VAR), which can be registered on a meter called a reactive power meter. The ratio of watts to volt-amps is called the power factor (a capacitive load has a power factor close to zero). Industrial customers with a poor power factor are penalised with higher tariffs and encouraged to improve their power factor.
