Calculating Complex Power: P+jQ

AI Thread Summary
Complex power is represented as P + jQ, where P is the real power and Q is the reactive power. The formula suggests that complex power is a phasor representation of the reactive and real power components, while the first term, P, is a scalar value and represents average power. The discussion raises questions about the relationship between phasors and scalars, noting that complex power can be expressed in both forms depending on the context. The confusion arises from the interpretation of "jQ," which indicates a phase difference between current and voltage. Overall, the conversation highlights the complexities in understanding the terminology and calculations related to complex power in electrical systems.
chopficaro
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power=P+P(cos(2wt))+Q(cos(2wt))

but

complex power = P+jQ

am i to assume that complex power is a phasor representation of the last two terms? why does this formula ignore the first term?
 
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and aparently it is also equal to

complex power =(Veff)(Ieff)

which is a scalar, but its also equal to

complex power=(Vphasor)(Iphasor)/2

which is a phasor

how can complex power be both a phasor and a scaler?
 
Please give this a read and see if it answers your question. I think it's good.
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/powerac.html"
 
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it did! tyvm!
 
chopficaro said:
power=P+P(cos(2wt))+Q(cos(2wt))

but

complex power = P+jQ

am i to assume that complex power is a phasor representation of the last two terms? why does this formula ignore the first term?

Surely Electrical Power is the Dot Produce between the V and I vectors. A dot product is a scalar.
What could "jQ" be? I and V may not be in phase but what has that to do with "complex power"? Is there some problem with actual terminology here?
 
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