Abstract
In this paper an adaptive nonlinear control strategy applied to a passively clamped two switch quasi resonant DC link converter is developed and simulated. First a nonlinear system modelling is derived with state variables of the input current and the output voltage by using power balance of the input and output. The system is linearized and decoupled, and then a state feedback law is obtained. For robust control to parameter perturbation, adaptive nonlinear control is introduced to the system. The simulation is provided to verify the validity of the control algorithm.