Patent ID: 7215041
Filing Date: 2007-05-08
Classification: H02M

Abstract:
1. A charging circuit for a frequency converter, comprising: a first feed line comprising a first constant current source therein; a second feed line comprising a second constant current source therein; an intermediate circuit capacitor connected between said first feed line and said second feed line, wherein said first constant current source limits a charging current of said intermediate circuit capacitor; an electronic control device that controls both said first constant current source and said second constant current source in parallel; and a current sensor that is located in only one of said first and second feed lines, wherein said current sensor generates an output signal that is provided to said electronic control device, wherein if said output signal is too high, then both said first constant current source and said second current source are switched off by said electronic control device and wherein if said output signal is too low, then both said first constant current source and said second current source are switched on by said electronic control device.