Abstract: A vehicle energy transmission circuit is equipped with an insulation fault detection circuit that has a fault current measurement apparatus, a first high-voltage connector, a second high-voltage connector, a ground potential connector, a first measuring resistor, a second measuring resistor and a measuring switch. One of the high-voltage connectors is connected in series with a connecting point via one of the measuring resistors and the measuring switch. The measuring resistor connects the other high-voltage connector directly to the connecting point. The connecting point is connected to the ground potential connector via the fault current measurement apparatus. The fault current measurement apparatus is configured to record a current that flows between the connecting point and the ground potential connector. The fault current measurement apparatus is configured to record this current when the measuring switch is open and closed.

Abstract: The invention relates to a protection device for voltage-limiting elements of a low-voltage line that extends out of a vehicle high-voltage region. A vehicle high-voltage device having a high-voltage region (HV), which is arranged in a housing (G), and having at least one low-voltage line (NL) is described. Said low-voltage line leaves the high-voltage region (HV) through an aperture (D). The high-voltage region is provided in the housing (G). The aperture (D) is provided in an outwardly delimiting housing wall (GW) of the housing (G). The at least one low-voltage line (NL) is connected to a ground potential (M) or to a connection therefor via a voltage-limiting element (V) and a current-limiting element (SG) connected in series with said voltage-limiting element.

Abstract: A charging circuit is equipped with a storage battery terminal, a direct-current terminal and an alternating-current terminal, which is connected to an alternating-current side of a rectifier of the charging circuit. The direct-current side of the rectifier is connected via a changeover switch to a first side of a DC-to-DC converter, wherein the changeover switch connects the first side of the DC-to-DC converter either to the direct-current terminal or to a first potential of the direct-current side of the rectifier. A second potential of the direct-current side of the rectifier is connected to the direct-current terminal via a diode. The reverse direction of the diode points toward the direct-current terminal. A second side of the DC-to-DC converter is connected to the storage battery terminal, to which the direct-current terminal is connected via an isolating switch. A vehicle electrical system having the charging circuit is also described.

Abstract: A multi-phase vehicle charging circuit equipped with an AC charging connector and with a load AC connector is provided. The charging connector is connected to an AC side of a rectifier circuit. The load AC connector is connected to a neutral conductor of the vehicle charging circuit and to a first phase of the AC side. At least one changeover switch connects at least one further phase of the AC side optionally to the neutral conductor or to an associated phase connector of the AC charging connector.

Abstract: A bidirectional vehicle charging circuit with a multi-phase bridge circuit having a first, a second, and a third half bridge is provided. A first connector is connected to the first and the third half bridge. A second connector is connected to the second and the third half bridge. A controller activates the first half bridge to convert a DC voltage into a first sinusoidal signal with positively offset negative half wave with a first amplitude. The controller activates the second half bridge to convert the DC voltage into a second sinusoidal signal with positively offset negative half wave with a second amplitude. The controller activates the third half bridge to convert the DC voltage into a square wave voltage with the potentials of the DC voltage as alternating square wave voltage level. The bridge circuit, once activated, generates one sinusoidal voltage with different amplitudes at the two connectors.

Abstract: A charging voltage converter on a vehicle is equipped with an upstream circuit, which includes at least one working inductor. Furthermore, the converter has a switching unit, which is connected downstream of the upstream circuit. The working inductor connects a first input potential of an input of the voltage converter to the switching unit. A second input potential of the input is connected via a reverse current blocking device of the upstream circuit to the switching unit.

Abstract: A vehicle electrical system is equipped with a high-voltage zone, a first low-voltage zone extending out of the high-voltage zone, a second low-voltage zone, and a safety device. The safety device connects the first low-voltage zone to the second low-voltage zone. The safety device has a galvanic isolation component or a voltage limiting element.

Abstract: A vehicle-based high-voltage charging circuit is provided with an AC voltage terminal, at least two galvanically isolating DC-DC converters designed as step-up converters and a rectifier via which the DC-DC converters are connected to the AC voltage terminal, and a changeover switch. The charging circuit has a first and a second DC voltage terminal selectably connected to the first DC-DC converter via the changeover switch. The charging circuit has a third DC voltage terminal connected to the second DC-DC converter, wherein the charging circuit also has a controller which is set up, in a first mode, to drive the DC-DC converters according to a first target output voltage which is at least 750 V and at most 1000 V, and, in a second mode, to drive the DC-DC converters according to a second target output voltage which is at most 480 V or at most 450 V.

Abstract: A method for monitoring at least one first and one second alternating-current output point in a vehicle is provided. The method includes detecting a total alternating current outputted by an inverter via a distribution point to the output points as a whole and also detecting at least one first alternating current, which flows in the first output point. The method includes determining a second alternating current, which flows in the second output point, as the difference between the total alternating current and the at least one first alternating current. The method includes comparing the at least one first alternating current and the second alternating current with a respective threshold value. The method also includes outputting an overload signal if at least one of the comparisons shows that the threshold value is exceeded. Furthermore, a vehicle-based unit and a vehicle charging circuit for carrying out the method are described.

Abstract: A method for detecting an isolation fault in a vehicle charging circuit is provided. The circuit has a DC voltage side which is isolated from a protective conductor potential, an AC voltage side and a controlled rectifier via which the DC voltage side is connected to the AC voltage side. The controlled rectifier is operated in a clocked mode according to an actuation signal. The following steps are also provided: measurement of a voltage present between DC voltage potentials of the DC voltage side or between a DC voltage potential of the DC voltage side and the protective conductor potential, and outputting of an isolation fault signal when the voltage contains an AC voltage component which partially or fully corresponds to the actuation signal and which has a signal strength above a predetermined threshold value.

Abstract: A vehicle electrical system is equipped with a DC charging connection, a rechargeable battery, a DC-DC converter and an electric drive. The DC-DC converter has a first side that is connected to a connecting point via a first switching device. The DC-DC converter has a second side to which the electric drive is connected and which is connected via a second switching device and to the connecting point. The connecting point is connected to the rechargeable battery. The DC charging connection is connected to one side of the first switching device that is connected to the first side of the DC-DC converter.

Abstract: An onboard electrical system is disclosed that includes first, second and third onboard electrical sub-systems for an electric drive unit, electric components and a vehicle battery of a vehicle, respectively. In addition, the system includes a charging terminal, wherein a changeover switch, a first switch element, and a second switch element of the onboard electrical system are physically separated from one another. The charging terminal is galvanically connected to the third onboard electrical sub-system by the first switch element and to the second onboard electrical sub-system by the changeover switch during an electric charging mode of the vehicle battery. The first onboard electrical sub-system is galvanically connected to the third onboard electrical sub-system of the second switch element and to the second onboard electrical sub-system by the changeover switch during a driving mode of the vehicle.

Abstract: A galvanically coupling DC-to-DC converter has a first side and a second side. The first side has a first potential and a second potential. The DC-to-DC converter has a first, a second and a third transistor. The transistors are connected in a series circuit via a first and a second connecting point and are connected between the potentials of the first side. A respective load inductor is connected to the two connecting points. The load inductors are each connected between one of the connecting points and one of two potentials of the second side of the DC-to-DC converter.

Abstract: A vehicle energy transmission circuit is equipped with an insulation fault detection circuit that has a fault current measurement apparatus, a first high-voltage connector, a second high-voltage connector, a ground potential connector, a first measuring resistor, a second measuring resistor and a measuring switch. One of the high-voltage connectors is connected in series with a connecting point via one of the measuring resistors and the measuring switch. The measuring resistor connects the other high-voltage connector directly to the connecting point. The connecting point is connected to the ground potential connector via the fault current measurement apparatus. The fault current measurement apparatus is configured to record a current that flows between the connecting point and the ground potential connector. The fault current measurement apparatus is configured to record this current when the measuring switch is open and closed.

Abstract: The invention relates to a protection device for voltage-limiting elements of a low-voltage line that extends out of a vehicle high-voltage region. A vehicle high-voltage device having a high-voltage region (HV), which is arranged in a housing (G), and having at least one low-voltage line (NL) is described. Said low-voltage line leaves the high-voltage region (HV) through an aperture (D). The high-voltage region is provided in the housing (G). The aperture (D) is provided in an outwardly delimiting housing wall (GW) of the housing (G). The at least one low-voltage line (NL) is connected to a ground potential (M) or to a connection therefor via a voltage-limiting element (V) and a current-limiting element (SG) connected in series with said voltage-limiting element.

Abstract: A high-voltage vehicle on-board electrical system is equipped with a ground potential and a high-voltage potential that is insulated from the ground potential by a two-stage insulation. The two-stage insulation has a first insulation device that insulates the high-voltage potential from a potential island. A second insulation device of the two-stage insulation insulates the potential island from the ground potential. The potential island is connected to the ground potential via a dissipating element. The dissipating element is configured, in the event of an insulation fault in the two-stage insulation, to generate a current that is below a hazard threshold and that is above a sensitivity threshold of an insulation monitor.

Abstract: A monitoring circuit for a high-voltage DC charging apparatus provides for the monitoring circuit to have a first high-voltage busbar and a second high-voltage busbar as well as a reference potential. This is electrically insulated from the high-voltage busbars. The monitoring circuit has a current sensor apparatus which is configured to capture a common-mode current flowing through the high-voltage busbars. The monitoring circuit also has a control device. The current sensor apparatus has a signal-transmitting connection to the control device, and the control device is configured to emit a fault signal if the magnitude of the common-mode current exceeds a limit. Furthermore, a DC voltage charging station, a DC voltage charging cable, a vehicle charging circuit and a method for detecting a fault in a high-voltage DC charging process are described.

Abstract: A method for detecting an insulation fault in a vehicle on-board electrical system having an HV and LV on-board electrical system branches. The LV branch has at least one first LV potential and a second LV potential that differs therefrom and corresponds to a ground potential of the vehicle on-board electrical system. The HV branch has positive HV negative HV potentials. These HV potentials are DC-isolated from the LV branch potentials. An insulation fault between at least one of the HV potentials and the first LV potential is detected by identifying a current flow. The current flow runs through a voltage limiting circuit connected between the ground potential and the first LV potential. This circuit connects the first LV potential, via a plurality of diodes, to a voltage limiting element connected to the ground potential of the vehicle on-board electrical system. A vehicle overvoltage protective circuit is also described.

Abstract: A monitored DC charging method for charging a vehicle rechargeable traction battery by way of a charging voltage source external to the vehicle is provided. The rechargeable traction battery has a nominal voltage of at least 500 V. In a checking step, the method includes detecting whether the charging voltage source has a surge protector which includes a voltage limiting element that is provided between a charging voltage potential and a ground potential of the charging voltage source and is set up to transition to a conductive state from a voltage below the nominal voltage. DC voltage is transmitted from the charging voltage to the rechargeable traction battery when the charging voltage source does not have the surge protector. At least one DC charging mode for transmitting DC voltage from the charging voltage source to the rechargeable traction battery is suppressed when the charging voltage source has the surge protector.

Abstract: A vehicle electrical system is equipped with at least one high-voltage consumer, a DC charging connection a rechargeable battery, a rectifier and a changeover switch. The high-voltage consumer is connected to the rechargeable battery by the changeover switch via a first switching device in a first switching position of the changeover switch and is connected to the rechargeable battery by the changeover switch in a second switching position of the changeover switch via a second switching device, wherein the DC charging connection is connected to the rechargeable battery via the first switching device.