The performance of the current stabilization control system in an aluminum smelter affects the quality and the quantity of the electrolytic products. This paper elaborates the power supply, in which the diode rectifiers and the self-saturable reactors could keep the series current stable, then describes the basic principle of the rectifier unit control and the series current control. A coordinate strategy is proposed to keep the series current stable, the self-saturable reactors are controlled by a proportional-integral control scheme and the on load tap changers of transformer are triggered by the errors between the setting value of the series voltage and the measured values of the series voltage. Simulation results on PSCAD/EMTDC show that the effectiveness of the proposed strategy to keep the series current stable.