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Instantaneous power doesn't have a frequency; it's instantaneous!

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Why reactive power is so confusing for engineers?

This is because reactive power concept is completely different from active(real) power,That is when we talk about active (real) power, we deal with two terms :The average value, and the instantaneous value.Both has significant values; let's say the average value is 5kw, where the instantaneous value maybe 2kw or 6kw, etc...On the otherhand, reactive power has always a Zero average value, and a different significant instantaneous values, but since the instantaneous value is difficult to measure, we always take the maximum instantaneous value of reactive power and deal with it as a textbook terminology (Reactive power) which is symbolized as Q and equals V I sintheta.And for the same reason (difficult to measure instantaneous value ) we easily deal with the average value of the active power other than the instantaneous value.As a brief:(Active power) symbolized P or known sometimes as real power equals V I cos thetarepresents the average value.(Reactive power) symbolized Q equals V I sin theta represents maximum instantaneous value.Someone can ask!Why not to take the maximum instantaneous value of average power such as reactive power as a terminology?Easily , why not to unites the two concepts ?!This is the answer of our main question (Why reactive power is so confusing for engineers?)This is easily because ,there is no useful meaning of using the instantaneous value for the active power, because it is a real produced power goes in one direction from source to load, where the average reactive power is always zero valued, since it goes back and forth in the network, and we are forced to deal with it in some way as an indication value and give it a unique terminology to express it as a fact that we cannot skip.In other words, you cannot compare two different things; apple and banana! Each one has a different taste.I hope that I answered the question, and dislodged some dust about this confusing concept, even I didn't take the boring mathematical path.


Why power factor using cos theta angle?

It's actually cos phi, where the Greek letter, 'phi', is the symbol for phase angle -the angle by which a load current lags or leads the supply current in an a.c. system (the Greek letter, 'theta', is used for the displacement of instantaneous values of current or voltage from the origin of a sine wave).The reason why power factor is a cosine requires you to understand the relationship between apparent power, true power, and reactive power. Apparent power is the vector sum of true power and reactive power, and can be represented, graphically, by the so-called 'power triangle'. In the power triangle, true power lies along the horizontal axis, reactive power lies along the perpendicular axis, and the apparent power forms the hypotenuse, and the angle between true power and apparent power represents the phase angle. By definition, power factor is the ratio between true power and apparent power, and this ratio corresponds to the cosine of the phase angle.From this, we can conclude that true power = apparent power x cos phi, where 'cos phi' is the 'factor' by which we must multiply apparent power to determine true power -i.e. the 'power factor'.


Why generators are rated at 0.8 lagging power factor?

Rated power factor


What is low power factor watt meter?

A wattmeter reads the true power of a load, regardless of its power factor.


Is it possible to transmit power with leading power factor?

The power factor depends on the properties of the load, and if any power factor correction is done it has to happen at the load, so that the current in the transmission lines is reduced. Correcting the power factor at the sending end fails to address the problem.

Related Questions

What is instantaneous power mean?

Instantaneous power refers to the power being consumed or generated at a specific moment in time. It is calculated as the product of the voltage and current at an exact instant and represents the rate at which energy is being transferred or converted at that particular point. It is commonly used in electrical engineering to analyze dynamic power consumption in circuits or systems.


How is instantaneous energy measured?

Instantaneous energy can be measured by calculating the power of a system at a specific moment. This can be done by measuring the rate of energy transfer or by using a power meter. The unit of measurement for instantaneous energy is typically in watts or joules per second.


What is the formula to calculate the instantaneous power in an electrical circuit?

The formula to calculate the instantaneous power in an electrical circuit is P V x I, where P represents power, V represents voltage, and I represents current.


What is the instantaneous power formula in physics and how is it calculated?

The instantaneous power formula in physics is P Fv, where P is power, F is force, and v is velocity. It is calculated by multiplying the force acting on an object by its velocity at a specific moment in time.


What is average power?

average power is the average of all the instantaneous values during one alternation..


What is an kilowatt meter?

A device used to indicate instantaneous power usage.


What is the difference between power factor and power booster?

Power factor is well defined and measures the difference between the phase of current and voltage. It varies from 1 to zero with 1 being associated with a pure resistive load. Since you multiply voltage times current to compute instantaneous power; if they are out of phase then you get reduced power. A power booster, in this context, would be a device that was designed to compensate for the our of phase situation and bring the phases more in line, effectively boosting power.


What is crest factor of online ups?

Crest factor is the ratio between the instantaneous peak current required by the load and the RMS current (RMS stands for Root Mean Square, which is a type of average). Most common electrical appliances exhibit a crest factor of 1.4 (1.4 is the ratio of the peak value of a sine wave to its RMS value). Computers and IT equipment with Power Factor Corrected power supplies exhibit a crest factor of 1.4. Personal computers and stackable hubs exhibit a crest factor of 2 to 3.


Why reactive power is so confusing for engineers?

This is because reactive power concept is completely different from active(real) power,That is when we talk about active (real) power, we deal with two terms :The average value, and the instantaneous value.Both has significant values; let's say the average value is 5kw, where the instantaneous value maybe 2kw or 6kw, etc...On the otherhand, reactive power has always a Zero average value, and a different significant instantaneous values, but since the instantaneous value is difficult to measure, we always take the maximum instantaneous value of reactive power and deal with it as a textbook terminology (Reactive power) which is symbolized as Q and equals V I sintheta.And for the same reason (difficult to measure instantaneous value ) we easily deal with the average value of the active power other than the instantaneous value.As a brief:(Active power) symbolized P or known sometimes as real power equals V I cos thetarepresents the average value.(Reactive power) symbolized Q equals V I sin theta represents maximum instantaneous value.Someone can ask!Why not to take the maximum instantaneous value of average power such as reactive power as a terminology?Easily , why not to unites the two concepts ?!This is the answer of our main question (Why reactive power is so confusing for engineers?)This is easily because ,there is no useful meaning of using the instantaneous value for the active power, because it is a real produced power goes in one direction from source to load, where the average reactive power is always zero valued, since it goes back and forth in the network, and we are forced to deal with it in some way as an indication value and give it a unique terminology to express it as a fact that we cannot skip.In other words, you cannot compare two different things; apple and banana! Each one has a different taste.I hope that I answered the question, and dislodged some dust about this confusing concept, even I didn't take the boring mathematical path.


What is the unit for average power?

Same as for instantaneous power or any other kind of power:Watt(same as joule per second)


What is the instantaneous power equation and how is it used in physics?

The instantaneous power equation is P Fv, where P is power, F is force, and v is velocity. This equation is used in physics to calculate the rate at which work is done or energy is transferred at a specific moment in time. It helps determine how much power is being exerted by a force on an object in motion.


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.