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Effective Current

A nonsinusoidal current is expressed by Eq. 5-32 as follows


It should be remembered that the coefficients I1, I2, and Ik are the amplitudes of the various harmonic components in the current. If the current represented by Eq. 5-42 were passed through a noninductive resistance of R ohms, the voltage across that resistor would become


The average power, as read by an indicating wattmeter, consumed by the noninductive resistance R, can be expressed either as


or as


where I in Eq. 5-45 is the effective value of the current expressed by Eq. 5-42. Hence


which, from Eq. 5-38, becomes



Last Update: 2011-01-13