A method and a device for automatic positive and negative ion balance control in a bipolar ion generator. The method may include applying bias voltage from a bias voltage source to a bias electrode from a power supply that includes an AC voltage generator and a voltage multiplying circuit of at least one cascade. The method may also include controlling a bias current flowing through the bias electrode for the purpose of stabilization of that current, wherein the step of controlling of the bias current is performed during charging of a capacitor in the voltage multiplying circuit.