Low-voltage discharge and actuation circuit for the traction converter of a vehicle

An on-board system for a vehicle which is propelled by an electrical machine, wherein the on-board system comprises:

• an electrical energy store configured to deliver direct current at a first voltage;
• an inverter configured to convert direct current at the first voltage into alternating current by which an electrical machine of a vehicle is operated;
• a back-up capacitor arranged in parallel with one input of the inverter;
• and
• an actuation circuit for the inverter, wherein the actuation circuit comprises:
• a direct voltage converter configured to convert direct current at the first voltage into direct current at an intermediate circuit voltage,
• a driver unit configured to generate, based on direct current at the intermediate circuit voltage, inverter control signals to switch elements of the inverter, and wherein the driver unit comprises at least one transformer circuit which is configured to generate, from direct current at the intermediate circuit voltage, different potentials for at least one of the inverter control signals,
• a discharge unit supplied with direct current at the intermediate circuit voltage, wherein the discharge unit is configured to switch, in response to a discharge control signal, a discharge resistor in parallel to an output of the direct voltage converter, and
• a control unit supplied with direct current at the intermediate circuit voltage, wherein the control unit is configured to generate, for the discharging of the back-up capacitor, a discharge control signal that causes the discharge unit to switch the discharge resistor in parallel to the output of the direct voltage converter.