What is Reactive Power in Electric Circuits?

[@blancayceleste]

Excellent! This is the only source I’ve found-videos or books-that explains where Q = Vrms * Irms * sin(phi) comes from in p(t). I really appreciate it. Thanks, and greetings from Argentina!

[@iain_explains]

I'm glad you found it helpful! Greetings from across the world!

[@prulikowski]

Very nicely explained, I would like to see a similar explanation based on voltages and currents of LC matching circuits, simple L-type match would be great to start with.

[@manutauer]

Thanks, so can we say that reactive power (due to L and C in circuits) is an unwanted phenomenon, but we have just to deal with it when we have some compobents? (It decreases the effective power -> therefore "unwanted")

[@iain_explains]

It depends on how you define "unwanted". It comes with having capacitors and inductors in a circuit - which you often want to have.

[@wolpumba4099]

**Abstract** This transcript explores the concept of reactive power in electrical circuits containing energy storage elements like capacitors. Here's a summary of the key points: **What is Power?** * Electrical power is the rate at which electrical energy flows (`P=dW/dt`). * Power can be expressed as the product of voltage and current (`P=VI`). **Power Flow in a Circuit with a Capacitor** * When a voltage source is connected to a capacitor-resistor circuit, current flows into the capacitor, storing energy. * When the source voltage decreases, the capacitor discharges, returning energy to the source. * Power flow into the capacitor represents energy storage; power flow back from the capacitor represents energy release. * Energy dissipated in the resistor is lower than the total energy supplied, reflecting the storage/release mechanism. **Sinusoidal Input and Phase Difference** * With a sinusoidal AC source, the current through the capacitor lags the voltage, creating a phase difference. * This phase difference leads to an oscillatory power flow, where energy is alternately stored and returned. **Active vs. Reactive Power** * **Active power** is the average power delivered to the circuit, causing energy dissipation in resistive elements. * **Reactive power** is the amplitude of the sinusoidal component of power flow due to the presence of energy storage elements (capacitors, inductors). It represents the power associated with energy storage and release, not dissipation. **Key Points about Reactive Power** * It is a real component of instantaneous power, not imaginary. * It exists when a circuit contains energy storage elements. * Its value depends on the amplitude of voltage and current, as well as the phase difference between them. disclaimer: i used gemini advanced 1.0 on 2024-02-26

[@AJ-fo3hp]

Active Reactive Newton 3rd law Pure energy storage circuit energy flows back and forth. I now understand p=v.i by looking other way dw/dt =dw/dq.dq/dt (dw/dq = v, dq/dt=i) Thank you for insightful technical educative video.

[@iain_explains]

I'm glad you liked it.

[@Ajay-ib1xk]

Great analysis for basic electrical engineers

[@iain_explains]

I'm glad you liked it.

[@drcpaintball]

If you put diode in the circuit doesnt "flows back to source" explanation fall apart???

[@deerajkumarj1408]

Sir, can you please explain as to why it is called reactive power

[@iain_explains]

Because "P" is the power that gets converted to another form in the resistor, and that is called "Active" power. So whoever started this naming convention decided to call "Q" the "Reactive" power.

[@deerajkumarj1408]

@@iain_explains Thank you sir

[@georgepalafox5967]

Great video sir! Q: at t=0, I presume the capacitor is fully charged, correct?

[@mgx9383]

No, it isn't. It starts charging from 0 V as seen on the vc(t) graph.

[@AJ-fo3hp]

Yes it is good question. Answer is: presume capacitor is fully charged to voltage V initially (t =0) Then one side you have fully charged (voltage V) capacitor and other side voltage source Vs if initially fully charged capacitor voltage V same as Vs( voltage source voltage) V = Vs then no electric charge flows due to no potential difference or equivalent potential if initially fully charged capacitor voltage V greater than Vs( voltage source voltage) V > Vs then electric charge flows from higher potential to lower potential. I.e., from fully charged capacitor to voltage source.(this is nothing but reactive power this is what explained in this video) if initially fully charged capacitor voltage V smaller than Vs( voltage source voltage) V < Vs then electric charge flows from higher potential to lower potential. I.e., from voltage source to fully charged capacitor.(this is nothing but active power this is what explained in this video)

[@Verbatino]

IMHO there should be few words how reactive power compensation works...

[@iain_explains]

Thanks for the suggestion. I've put it on my "to do" list