0
\$\begingroup\$

Many sources I've read state that reactive power is important because it helps maintain voltage and magnetic fields in inductors, but in a circuit at its resonance frequency, the inductive and capacitive reactances should cancel so there would be no reactive power. What happens in this situation?

\$\endgroup\$

1 Answer 1

-1
\$\begingroup\$

well I don't think I know what "reactive power" is in the context of your question. I have seen "reactive power" used in AC power distribution systems where it is a bad thing. Power companies want loads to be resistive and if you have a factory say with a bunch of motors running they may make you put capacitors across the line to phase shift the load back to resistive.

However at resonance there is still current flowing in the inductor, so it will still have a magnetic field. It just that as you state the combined load is resistive so the current and voltage (across the load) are in phase, and the power is not reactive.If you have access to a circuit simulation program such as Spice, simulate a RLC circuit at resonance. You will see current in all three parts. In an ideal circuit like that the current in the inductor and capacitor will always be 90deg out of phase, but the phase-current relationship of the circuit will change with frequency.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.