A routine is presented to determine the optimal parameters of a cascade control using a genetic algorithm to improve the transient response a dc-dc converter. The effects on the behavior of the converter are analyzed. The parameters are determined using Ziegler-Nichols (ZN), Takahashi (TK) and the genetic algorithm (GA) methods. Optimal parameters of a PID-PI cascade control for different loads are found using the proposed cost function. The obtained parameters reduce overvoltage and oscillations while improving the dynamics of the system. The concept is validated by measurements taken from a hardware test setup of an isolated bidirectional dual active bridge.