A power supply system for a vehicle includes a high-voltage battery that supplies electric power to an on-vehicle motor, a low-voltage battery that supplies electric power to a plurality of on-vehicle auxiliary machines, a DC/DC converter that changes voltage of an output from the high-voltage battery and supplies the resulting output to the low-voltage battery, and a controller that detects a working state of at least one of the plurality of on-vehicle auxiliary machines and controls operation of the DC/DC converter in accordance with the detected working state.

A diagnosis method for the switching elements in a bidirectional DC-to-DC voltage converter comprising: charging a capacitor in the bidirectional DC-to-DC voltage converter to a predetermined first test voltage, then specifically actuating the switching elements in the bidirectional DC-to-DC voltage converter, and evaluating the voltage in the charged capacitor of the bidirectional DC-to-DC converter to identify a faulty switching element within the switching elements in the bidirectional DC-to-DC voltage converter.

A system may be provided that may include a first battery, and an inverter coupled to the battery. The system may also include a first active filter including a first switch element, second switch element, third switch element, and fourth switch element. Each switch element may be coupled to the first battery or the inverter. The first, second, third, and fourth switch elements may be configured to increase or decrease an applied voltage or current of the first battery.

The invention relates to charging an electrical energy store by means of a converter. In this case the converter monitors an electrical connection between the converter and the electrical energy store. If an interruption of the electrical connection between the converter and the electrical energy store is detected, for example, the opening of a circuit breaker between the electrical energy store and the converter, the further provision of electrical power for charging the electrical energy store through is immediately prevented by the converter. In this way, dangerous voltage rises on the converter can be avoided.

The invention relates to a method for operating an electrical system (1) having a high-voltage section (2) and a low-voltage section (3) which are electrically connected to one another by means of a DC-DC converter (4), wherein the low-voltage section (3) has at least one rechargeable energy store (8) and at least one electrical consumer (9), wherein the DC-DC converter (4) is operated on the basis of an electrical load (P) acting on the low-voltage section (3). In order to determine the load (P), provision is made for all currents flowing through the DC-DC converter (4) to be recorded and added to one another.

An electrical drive system having multiple drive units for motor vehicles, especially for pure electric vehicles, and a method for operating the drive system.

A power supply system for a vehicle includes a high-voltage battery that supplies electric power to an on-vehicle motor, a low-voltage battery that supplies electric power to a plurality of on-vehicle auxiliary machines, a DC/DC converter that changes voltage of an output from the high-voltage battery and supplies the resulting output to the low-voltage battery, and a controller that detects a working state of at least one of the plurality of on-vehicle auxiliary machines and controls operation of the DC/DC converter in accordance with the detected working state.

A motor vehicle comprises a motor configured to input and output power for driving; an inverter configured to drive the motor; a power storage device configured to transmit electric power to and from the motor; a system main relay configured to connect and disconnect the power storage device with and from a power line on an inverter-side; and a control device configured to enable the motor vehicle to be driven with turning on the system main relay according to a predetermined procedure in response to a system on-operation. The motor vehicle does not perform failure diagnosis of the inverter when an abnormality signal of the inverter is generated before a predetermined time after the system main relay is turned on in response to the system on-operation, while performing the failure diagnosis when the abnormality signal of the inverter is generated after the predetermined time.

A system, computer readable medium, and a method for monitoring power module degradation in a vehicle are provided. The method includes determining a structure function of a power module, determining a change in the structure function based on a comparison between the structure function and an initial or baseline structure function associated with the power module, outputting a degradation determination result based on the change in the structure function, and generating an alert when the degradation determination result exceeds a predetermined or adaptively determined degradation criterion value.

The invention relates to the diagnosis of the switching elements in a bidirectional DC-to-DC voltage converter. By charging a capacitor in the DC-to-DC voltage converter and then specifically actuating the switching elements and evaluating the voltage in the charged capacitor of the DC-to-DC converter, it is possible to identify a faulty switching element.