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Is there any active or reactive power in dc current?
Active, yes; reactive, no.
Why reactive power is named as reactive?
Actually reactive power is a power which flows in between load to source which is a reactive action of the power given from source to load.the given power to load will not be utilised fully.some power will be oscillating from load to source.this is called reactive power.
What happens to reactive power in a circuit that has both inductance and capacitance?
Inductors are considered to be a load for reactive power, meaning that they will draw reactive power from the system. Capacitors are considered to be sourced of reactive power, they feed reactive power into the system. If you have a circuit that is at unity (balanced with inductors and capacitors) no reactive power will be drawn from the source. You will have unity power factor. If your circuit is more inductive than capacitive it will be drawing reactive power from the source. The opposite is also true for capacitors.
How reactive power contributes to additional losses?
Reactive power is well known as that component which is shunted back and forth from the source to the load over the AC cycle. However, this does not mean the system has no reactive power losses. In fact they would be quite high. Loss is always measured with respect to load and not the source. When we term it reactive power loss, it is not the amount of power taken away from the source and not returned. That way, there would absolutely be no reactive loss at all because all the energy stored in the reactive elements are anyway returned. The idea is after all to provide the power to the load. So, the loss represents the amount of power unable to reach the load. The power lines are not purely resistive. They comprise considerable level of reactive elements especially line inductance.Now, the active power which actually runs the load is never a separate entity. It co-exists with reactive power because the reactive (more so inductive) components of the load need to be energized in order to power the load. Reactive power loss is thus that amount of power which is deficient or 'not supplied' to the storage (reactive) elements of the load because of the reactive elements on the line. Thus the loss is always to be visualized in terms of load. That is why the complete return of reactive power to the source in the negative cycle has got nothing to do with loss understanding actually.Hope this helps!
Which excitation synchronous motor drawn reactive power?
Hi, Under excitation - inductive reactive power Over excitation - Capacitive reactive power.
Why there is no reactive power in DC system?
In case of dc there is no reactive components and current drawn from the supply is in phase with the voltage.due to absence of inductor and capacitor the reactive power demand in dc is zero.
Is there any active or reactive power in dc current?
Active, yes; reactive, no.
Why No reactive power on DC circuit don't give answer as W equals 23.14fL as f is zero Xc as infinity and Xl as zero?
Reactive power shows up in AC when the voltage and current waves aren't in sync. In DC you don't have waves, so you don't have reactive power. That's as simply as I can put it.
What is the var meter?
A VAR Meter is used to measure Reactive Power in AC Circuits - Pure reactive components dissipate zero power, which makes sense in a DC circuit, as a capacitor passes no DC current and an inductor displaces no voltage. Yet, in an AC circuit, the reactive components "seem" to dissipate power, as current passes through the capacitor and the inductor sees a voltage drop. This counterfeit power is called "reactive power" and is measured not in Watts, but in VARs (Volt-Amps-Reactive). Its mathematical formula symbol is "Q". A VAR Meter is used to measure Reactive Power in AC Circuits - Pure reactive components dissipate zero power, which makes sense in a DC circuit, as a capacitor passes no DC current and an inductor displaces no voltage. Yet, in an AC circuit, the reactive components "seem" to dissipate power, as current passes through the capacitor and the inductor sees a voltage drop. This counterfeit power is called "reactive power" and is measured not in Watts, but in VARs (Volt-Amps-Reactive). Its mathematical formula symbol is "Q".
Can you transfer power without reactive power?
I'm not sure the question makes sense. In a word, "yes". Think of a simple DC source and a resistor. No reactive power there, but power is being dissipated by the resistor ("transferred" from the DC source). If you're talking about AC circuits and "transferring" means going through a transformer, then, again, "yes" because whatever reactance the transformer has can be offset by a capacitor with the same. So you would have no reactive power, but power would be transferred.
How reactive power is used?
Reactive power (VARS) is required to maintain the voltage to deliver active power (watts) through transmission lines.Motor loads and other loads require reactive power to convert the flow of electrons into useful work.When there is not enough reactive power, the voltage sags down and it is not possible to push the power demanded by loads through the lines.
What is the importance of reactive power in transmission lines?
Reactive power is the electrical power that oscillate between the magnetic field of an inductor and the electric filed of the capacitor. Reactive Power Cannot Converts to non-electrical power e.g. heat, light & torque. Instantaneous reactive power equal to the multiplication instantaneous current, instantaneous voltage and the sinusoidal of phase difference of current & voltage. It only present in ac power if there is any phase difference between instantaneous current and instantaneous voltage. During complete cycle average reactive power is zero. Active power is the energy supplied to run a motor, heat a home, or illuminate an electric light bulb.Reactive power provides the important function of regulating voltage. If voltage on the system is not high enough, active power cannot be supplied. Reactive power is used to provide the voltage levels necessary for active power to do useful work. Reactive power is essential to move active power through the transmission and distribution system to the customer .Reactive power is required to maintain the voltage to deliver active power (watts) through transmision lines. When there is not enough reactive power, the voltage sags down and it is not possible to push the power demanded by loads through the lines.
Why there are no losses in DC transmission?
There are losses in d.c. transmission lines, due to their resistance. But there are no reactive losses. So, d.c. transmission lines have less losses in comparison to an equivalent a.c. transmission line.
Why reactive power is named as reactive?
Actually reactive power is a power which flows in between load to source which is a reactive action of the power given from source to load.the given power to load will not be utilised fully.some power will be oscillating from load to source.this is called reactive power.
How real losses increase with increase of reactive power?
As far as the load is concerned, they don't. But, as far as the supply lines are concerned, they have to cater for an increase in load current and, therefore, increased line losses, if the reactive power of the load increases.
Why dc supply is a unity power factor?
Power factor is a measure of the ratio between the "True Power" and the "Apparent Power" of a system. THe variation from unity arises from the effect of certain components (namely capacitors and inductors) on an AC waveform, causing a phase shift between the current and the voltage. As a DC supply does not suffer from these reactive losses there is no reactive power and the current and voltage are always "in phase". With a phase angle of 0 degrees, the power factor is the cosine of the angle... cos 0 = 1 therefore unity power factor!
What happens to reactive power in a circuit that has both inductance and capacitance?
Inductors are considered to be a load for reactive power, meaning that they will draw reactive power from the system. Capacitors are considered to be sourced of reactive power, they feed reactive power into the system. If you have a circuit that is at unity (balanced with inductors and capacitors) no reactive power will be drawn from the source. You will have unity power factor. If your circuit is more inductive than capacitive it will be drawing reactive power from the source. The opposite is also true for capacitors.
