Stability and graphical analysis of first-order pulse-width-modulated sampled-data regulator systems

Pulse-width-modulated sampled-data systems are described by nonlinear difference equations which do not lend themselves to an exact analytic treatment. This paper presents a graphical technique for the analysis of PWM sampled-data systems with first-order plants. This technique provides a sufficient condition for asymptotic stability in the large, a method for examining the damping properties of the system, a method for computing the step response from any initial condition and, finally, a method for observing and interpreting the effect of varying the system parameters on the step response of the system.