The goal of our work is the development of modern control laws for a low-pressure mercury-argon discharge lamp (UV-C lamp) powered by a serial multicell converter for water purification. In the previous article, we presented the multicellular converters series: operation, modeling and control. We also exposed the control modulating cyclic reports which was dedicated to the control of the voltages and the flying capacitors, it was intended to ensure the balancing of the voltages across the switches. Current regulation is done by introducing a classical PI-type regulator synthesized by the pole-placement method, which made it possible to have a good setpoint monitoring despite the presence of the perturbation on the arc current and parametric variations on the arc resistance. After having tested the robustness of the PI regulator vis-à-vis the parametric variations of the arc resistance or the arc current, which are inversely proportional and which vary according to the temperature. The goal of our work is the development of a modern control law for a discharge lamp powered by a serial multicell converter. The first control is the regulation by a traditional PI, but this control has not been very robust. For this, it has been replaced by a fuzzy regulator (Mamdani) to improve the performance of our electronic discharge lamp-Ballast system