Patent ID: 7786694

Claim:
A converter system, comprising: at least one supply module configured to provide a unipolar, intermediate circuit voltage; at least one drive module powerable by the intermediate circuit voltage, each drive module including at least one inverter configured to power at least one electric motor; at least one buffer module configured to store energy; and a power cable electrically connecting the supply module to the buffer module; wherein the buffer module is configured to be supplied with energy for periods of time when the intermediate circuit voltage exceeds a first critical value and an overall regenerative power of a first drive module exceeds a motive power of a second drive module to store the supplied energy, and to supply the stored energy to at least one drive module when a total motive power of the at least one drive module exceeds the regenerative power to power the corresponding electric motor; wherein the buffer module includes a capacitor and a diode, and a cathode of the diode is directly connected to a negative plate of the capacitor.