CURRENT CONVERSION

摘要

A current converter is used to convert an alternating current (AC) to a direct current (DC) and/or vice versa or for DC/DC current conversion, wherein an input side of the current converter is connected to a power supply network. The current converter comprises at least one electric or electronic valve adapted for repeatedly switching on and off an electric connection and thereby operating the current converter. A repetition frequency of the switching of the at least one valve is varied during operation of the current converter. For example, PWM signals (S1 to S9) with varying distances to each other are used in order to control the operation of the current converter. A reference function (F) may be used to calculate the widths of the PWM signals (S1 to S9) correspondingly to sinusoidal voltage of the power supply network.