DC/DC converter output current check: Objectives

The DC/DC converter integrated into the electrical machine electronics guarantees the voltage supply of the 12 V vehicle electrical system. To do this, the high voltage from the high-voltage electrical system is converted into the correct voltage for the 12 V vehicle electrical system.

The DC/DC converter monitors the internally flowing currents and the output current. If one of the monitored currents exceeds a threshold value (overload current), the output current and the output voltage are limited. At the same time, one of the specified faults is entered in the fault memory. This protects the DC/DC converter components from damage (component protection).

The fault cause is not yet clearly defined through this monitoring. The cause of the overload current may be an internal fault in the DC/DC converter or a faulty component in the 12 V vehicle electrical system (line, consumer, 12 V battery). If an internal fault is present in the DC/DC converter, it can be detected on the basis of the DC/DC converter's output current curve.