Power supply device for a nonlinear, time-varying load, - wherein the power supply device has a power system having a plurality of phases, - wherein the nonlinear, time-varying load and a reactive power compensator are connected to the phases of the power system, - wherein the reactive power compensator is embodied as a multilevel converter having a plurality of strands, - wherein the strands of the multilevel converter are connected on the one hand to one of the phases of the power system in each case and on the other hand to one another at a common star point, wherein the power supply device has a filter circuit, by way of which harmonics of load and converter currents can be filtered, - wherein the filter circuit has a plurality of strands, characterised in that - the strands of the filter circuit are connected on the one hand to one of the phases of the power system in each case and on the other hand to one another at a common star point of the filter circuit, - the common star point of the multilevel converter is connected to the star point of the filter circuit such that the common star point of the multilevel converter is connected both via the strands of the multilevel converter and also via the filter circuit to the phases of the power system, and - the connection via the filter circuit is embodied in such a way that there is a low-resistance connection of the common star point of the multilevel converter to the phases of the power system with respect to the power zero sequence system of the power system and a high-resistance connection with respect to the power positive sequence system of the power system and to the power negative sequence system of the power system. - wherein the power supply device has a power system having a plurality of phases, - wherein the nonlinear, time-varying load and a reactive power compensator are connected to the phases of the power system, - wherein the reactive power compensator is embodied as a multilevel converter having a plurality of strands, - wherein the strands of the multilevel converter are connected on the one hand to one of the phases of the power system in each case and on the other hand to one another at a common star point, wherein the power supply device has a filter circuit, by way of which harmonics of load and converter currents can be filtered, - wherein the filter circuit has a plurality of strands, - the strands of the filter circuit are connected on the one hand to one of the phases of the power system in each case and on the other hand to one another at a common star point of the filter circuit, - the common star point of the multilevel converter is connected to the star point of the filter circuit such that the common star point of the multilevel converter is connected both via the strands of the multilevel converter and also via the filter circuit to the phases of the power system, and - the connection via the filter circuit is embodied in such a way that there is a low-resistance connection of the common star point of the multilevel converter to the phases of the power system with respect to the power zero sequence system of the power system and a high-resistance connection with respect to the power positive sequence system of the power system and to the power negative sequence system of the power system.