In a R+1/(jwC) load (AC)voltage lags current with θ degrees. Reactive power Q is negative because sin(θ) is negative. My question is how can a capacitive load deliver power to the source wich is supposed to supply the power? Im sure I do not completely understand the subject, can someone explain my faults? Thank you for your help, Nick.
It is a common misunderstanding that a voltage source must also be a power source. That's not true, an ideal voltage source merely constrains the voltage between two points in a circuit. Current may flow in either direction through the source, causing it to consume power or provide power. Think about a rechargeable battery, for example. If you have some kind of standby power supply, the battery will be charging (consuming power) part of the time and supply power part of the time.
I found a good explanation of what I am trying to ask, I will post the link for anyone else who is interested. What does it mean for reactive power to be delivered or consumed