ELEC1103 Lecture Notes - Lecture 18: Phasor, Root Mean Square

• School: University of Sydney
• Department: Electrical Engineering
• Course: ELEC1103
• Professor: omid kavehei

Document Summary

Without a time element to a signal, we can analyse sinusoidal signals with complex numbers, using the magnitude and phase of the signal. A sinusoid is a signal that has the form of the sine or cosine function. To compare 2 sinusoids, they both have to be of the form asin( t + ) We can perform the necessary transformations using the trig identities we know. V cos( t + ) = v e j( t+ ) Phasor transforms make differentiation and integration much easier. Instantaneous power v(t) = v mcos( t + v ) v m v (phasor domain transform) Where vis the amplitude of sinusoidal signal m i(t) = imcos( t + i) im i. V mimcos( t + v )cos( t + i) p = imv m v + i. For both above equations, if v(t) or i(t) is in the form x(t) = xmcos( t + x)