Supply unit for a motor control with determination of the direct current component of a Rogowski flow measurement and method for determining the direct current component of a Rogowski current measurement at a supply unit for a motor control

摘要

The invention relates to a supply unit for a motor control, with a three-phase supply input, a three-phase rectifier which is connected to the three-phase supply input; a DC voltage intermediate circuit which is connected to the three-phase rectifier, a computing unit and a Rogowski measuring device, set up to measure the phase current and output it to the computing unit. According to the invention, the supply unit has a network angle measuring device, a point in time being stored in the computing unit at which it can be assumed that the phase current is zero and the computing unit is set up to measure a phase current value measured by the Rogowski measuring device at the predetermined point in time save as offset value and correct a phase current value measured outside of the predetermined time by the Rogowski measuring device by subtracting the offset value and output the corrected phase current value or a value derived therefrom. The invention also relates to a corresponding method for determining the DC component of a Rogowski current measurement in a supply unit for an engine control.