This article presents the fundamental theory of inverse optimal control problems and its application in output voltage regulation of power converter circuits. An inverse optimal control problem avoids the explicit solution of the Hamilton-Jacobi-Bellman equation that appears in the formulation of an optimal control problem. Some analytical and numerical developments are performed here in order to propose how to deliver optimally a desired level of power to a load. Simulation results show promising predictions of improvement in regulation capabilities of the power converter circuit in spite of environmental perturbations. Ongoing tasks include experimental verification of theoretical predictions and optimality tests.