Stability analysis of feedback controlled resonant DC-DC converter using Poincare map function

The stability analysis of the buck member of a dual channel resonant DC-DC converter family is reported. The study is confined to the symmetrical continuous current mode. The output voltage of the converter is controlled by a feedback loop applying constant frequency PWM. The dynamic analysis applies to stability criterion the positions of the characteristic multipliers of the Jacobian matrix belonging to the Poincare map function defined around the fixed point located in the Poincare plane where the trajectory of the variable structure, piecewise linear, nonlinear system pierces through the plane. The study reveals that the process loses its stability as a result of varying the loop gain