A plasma generator having a housing surrounding an ionization chamber, at least one working-fluid supply line leading into the ionization chamber, the ionization chamber having at least one outlet opening, at least one electric coil arrangement which surrounds at least one area of the ionization chamber, the coil arrangement being electrically connected with a high-frequency alternating-current source (AC) which is constructed such that it applies a high-frequency electric alternating current to at least one coil of the coil arrangement, is wherein a further current source (DC) is provided which is constructed such that it applies a direct voltage or an alternating voltage of a frequency lower than that of the voltage supplied by the high-frequency alternating current source (AC) to at least one coil of the coil arrangement.