5.6 Average Power, Reactive Power and Power Factor cont.

P(t) = v(t)i(t) = VPcos(wt)IPcos(wt - q)

= 0.5VPIP cos(q){1 + cos(2wt)} + 0.5VPIP sin(q){-sin(2wt)}

Recall from text p. 39 that XRMS = XPEAK/Ö2 \ since 2 = Ö2Ö2,

P(t) = VRMSIRMS cos(q){1 + cos(2wt)} + VRMSIRMS sin(q){-sin(2wt)}

\ P(t) = PfP(t) + QfQ(t), where …

P = VRMSIRMS cos(q) & Q = VRMSIRMS sin(q)

are constants and

fP(t) = {1 + cos(2wt)} and fQ(t) = -sin(2wt)

are time functions

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