The high voltage power supply for magnetron, used for the modular microwave generators in industrial applications, is a classical design. This system is composed of a single-phase high voltage transformer with shunts supplying a cell, composed of a capacitor and a diode, which doubles the voltage and stabilizes the current. In this case, the leakage fluxes in the magnetic shunts are of the same order in the primary and the secondary fluxes. In this work, a π quadruple model of this leakage transformer is developed taking account the saturation phenomena and the stabilization of the magnetron current. From the model of the transformer we will define a strategy of optimization aims at restricting the study of the effect of simultaneous variation of pertinent parameters on the magnetron current. This will lead to find an optimized solution of the transformer. The later, with reduced volume, weight, and therefore cost, will make the power supply more economical.