In this work the problem of regulation of the Root Mean Square (RMS) value of the current for Series Resonant Converter (SRC) is addressed. The self-oscillating behavior is ensured by an amplitude-modulation like control law and the RMS value is estimated with a proposed hybrid system. The closed-loop regulation is done with a Proportional-Integral (PI) controller with anti-windup scheme, and a set of Linear Matrix Inequalities (LMIs) is introduced to tune the gains. The knowledge of a reference trajectory is not needed to implement the controller, and it is shown to be effective in simulation considering uncertain parameters.