Abstract: The warm-up period of the internal combustion engine is reduced by operating an electric machine as an additional load of the combustion engine in order to obtain a specific excessive increase in the heat loss of combustion engine. To this end, the magnetizing current of the electric machine such as, for example, a starter generator with field-oriented regulation, can be regulated in order to obtain a specific decrease in the degree of efficiency of the electric machine.

Abstract: The circuit arrangement has two battery connections for a first battery, a DC/AC converter whose AC input can be connected to a power converter, a control unit and a component for decoupling the voltage of the first battery from the voltage on DC input of the DC/AC converter. Said component has exactly two power connections and at least one control connection. A voltage drop between the power connections can be varied by means of the control connection. The circuit arrangement has at least one connection enabling a consumer system to be connected parallel to the DC input of the DC/AC converter. When the first battery is connected, the first battery and the component form a series connection via the power connections thereof, said series connection being mounted parallel to the DC input of the DC/AC converter. The control unit is connected to the control connection of the element.

Abstract: Two low-voltage energy storage devices (B1 and B2) are provided in an arrangement that ensures, on the one hand, a high start power in the vehicle electrical system, resulting from being connected to a higher-level voltage, for a starter generator (SG) that is coupled to an internal combustion engine. The arrangement additionally ensures, on the other hand, full compatibility with low-voltage vehicle electrical system consumers (VB). The arrangement allows the two low-voltage energy storage devices (B1 and B2), either separately or when connected in parallel, to supply the vehicle electrical system consumers (VB) with a low voltage. In addition, the arrangement allows the two low-voltage energy storage devices (B1 and B2), when connected in series, to provide the high start power with increased voltage and correspondingly reduced current intensity at least for a cold start of the starter generator (SG).

Abstract: The circuit arrangement has two battery connections for a first battery, a DC/AC converter whose AC input can be connected to a power converter, a control unit and a component for decoupling the voltage of the first battery from the voltage on DC input of the DC/AC converter. Said component has exactly two power connections and at least one control connection. A voltage drop between the power connections can be varied by means of the control connection. The circuit arrangement has at least one connection enabling a consumer system to be connected parallel to the DC input of the DC/AC converter. When the first battery is connected, the first battery and the component form a series connection via the power connections thereof, said series connection being mounted parallel to the DC input of the DC/AC converter. The control unit is connected to the control connection of the element.

Abstract: In order to control a converter (1) which is used to convert a primary input voltage (UE) into a secondary output voltage (Ua), a voltage value (Uv) derived from a secondarily detected real voltage (Uist) is compared with a reference value (UR), and a control signal (Sa) is produced as a criterion which triggers the disconnection of said converter (1) if said reference value is exceeded. The voltage value (Uv) or the reference value (UR) is manipulated during a monitoring phase in such a way that said parameter is met.

Abstract: According to the invention, the wwarm-up period of the internal combustion engine is reduced by operating the electric machine as an additional load of the combustion engine in order to obtain a specific excessive increase in the heat loss of the same. To this end, the magnetizing current e.g. of a starter generator with field-oriented regulation can be regulated in order to obtain a specific decrease in the degree of efficiency of the starter generator.

Abstract: In order to control a converter (1) which is used to convert a primary input voltage (UE) into a secondary output voltage (Ua), a voltage value (Uv) derived from a secondarily detected real voltage (U1st) is compared with a reference value (UR), and a control signal (Sa) is produced as a criterion which triggers the disconnection of said converter (1) if said reference value is exceeded. The voltage value (Uv) or the reference value (UR) is manipulated during a monitoring phase in such a way that said parameter is met.

Abstract: Two low-voltage energy storage devices (B1 and B2) are provided in an arrangement that ensures, on the one hand, a high start power in the vehicle electrical system, resulting from being connected to a higher-level voltage, for a starter generator (SG) that is coupled to an internal combustion engine. The arrangement additionally ensures, on the other hand, full compatibility with low-voltage vehicle electrical system consumers (VB). The arrangement allows the two low-voltage energy storage devices (B1 and B2), either separately or when connected in parallel, to supply the vehicle electrical system consumers (VB) with a low voltage. In addition, the arrangement allows the two low-voltage energy storage devices (B1 and B2), when connected in series, to provide the high start power with increased voltage and correspondingly reduced current intensity at least for a cold start of the starter generator (SG).

Abstract: In order to reduce the battery load, a second elevated onboard electrical system voltage is provided at least for high-current consuming components. The voltage is derived from the battery voltage via a step-up switching regulator (SUSR) or is supplied by a starter-generator (SG) via a converter (CONV) in the generator mode of the starter-generator, which is coupled with an internal combustion engine (ICE) of the vehicle. The step-up switching regulator is used for battery supply of a start capacitor (CAP) and the converter is used for triggering of the starter-generator to start the internal combustion engine.