24. Phasors
Periodic signals are introduced. Sinusoidal steady state analysis is introduced. The basic parameters (magnitude, angular frequency, and phase angle) of a cosine function are given. Mixed notation of radians per second and degrees within a cosine function is given rationale. The complex expression of a sinusoid is given. The relationship between sinusoids and complex numbers is demonstrated graphically. Sinusoidal steady state analysis is called phasor analysis. Time-domain and phasor domain are introduced and the importance of keeping them separate is discussed. Converting voltages and currents from the time domain to the phasor domain is demonstrated. Conversion between polar and rectangular forms is shown. Conversion from the phasor domain to the time domain is shown. Phasor techniques for adding sinusoidal functions of the same frequency are demonstrated. The importance of checking the value and sign of the angle in polar form is stressed.