Patent ID: 11916431
Assignee: ABB SCHWEIZ AG
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 12:
13. A method for balancing the voltage of a DC split link with a positive line, a floating midpoint, and a negative DC line in a converter, wherein a first DC capacitance is arranged between the positive line and the floating midpoint, and a second DC capacitance is arranged between the negative DC line and the floating midpoint, wherein a first resistor is arranged in parallel to the first DC capacitance, and a second resistor is arranged in parallel to the second DC capacitance, wherein a first switchable contact is arranged in series with the first resistor, and a second switchable contact is arranged in series with the second resistor, and wherein the first and second switchable contacts are of type “normal-on,” the method comprising:
starting up the converter;
starting to pre-charge the first and the second DC capacitances; and
engaging the first and second resistors and balancing the voltage at the first and the second DC capacitances at least during pre-charging the DC capacitances.