A new quick transient response digital control dc-dc converter with smart bias function

The purpose of this paper is to present a new quick transient response digital control dc-dc converter with smart bias function and its design criterion. In the proposed method, not only the conventional P-I-D control as the feedback one but also the smart bias function as the feedforward one is used. The smart bias function consists of two superior functions. One is the steady-state function for the expanse of regulation range of output voltage, and another is exponential function for the improvement of transient response. By using these functions, the proposed method has no steady-state-error against the changes of the input voltage and the output current. In addition, the undershoot of output voltage and the overshoot of reactor current are approximately 92% and 89% smaller than the conventional method in the step change of load resistance from 100Ω to 5Ω. Especially, the convergence time for output voltage is converged instantly. It is confirmed that the smart bias function control technique is useful to realize the high performance digital control method.