Search

DE-102024003968-B3 - Dual inverter and method for charging a battery of a high-voltage system

DE102024003968B3DE 102024003968 B3DE102024003968 B3DE 102024003968B3DE-102024003968-B3

Abstract

The invention relates to a dual inverter (1) comprising two inverters (2.1, 2.2), each comprising three half-bridges made of semiconductor switches (S1 to S12), each with three phase connections, between which an electric machine (3) is connected, the machine having three stator windings (L1, L2, L3), wherein a switchable connection (4) is provided between the high-voltage potentials (HV+, HV-) of the two inverters (2.1, 2.2) which are connected to a battery (5), wherein a disconnecting element (S-drive) is arranged between the battery (5) and one of the inverters (2.1, 2.2) and/or between the two inverters (2.1, 2.2) in one of the two high-voltage potentials (HV+, HV-) of the switchable connection (4), wherein a connection point for connection to a DC charging station (12) or to an AC charging station (14) is provided on one side of each stator winding (L1, L2, L3). L3) is brought out of the double inverter (1). A switching element (S_DC_800_P) is arranged for connecting the positive high-voltage potential (HV+) to a positive terminal (DC_P) for the DC charging station (12), wherein a switching element (S_DC_N) is arranged for connecting the negative high-voltage potential (HV-) to a negative terminal (DC_N) for the DC charging station (12). Two further switching elements (S_AC_L1, S_AC_L2) are arranged to connect one phase terminal (U, V, W) for an AC charging station (14) to one connection point of one of the stator windings (L1, L2, L3), wherein the positive terminal (DC_P) is connected to one of these phase terminals (U, V, W) and the negative terminal (DC_N) is connected to the other of these phase terminals (U, V, W) to a common pin of a connector for optional connection of the DC charging station (12) and the AC charging station (14).

Inventors

  • Urs Boehme
  • Akin Candir

Assignees

  • Mercedes-Benz Group AG

Dates

Publication Date
20260513
Application Date
20241128

Claims (6)

  1. A dual inverter (1) comprising two inverters (2.1, 2.2), each comprising three half-bridges made of semiconductor switches (S1 to S12), each with three phase connections, between which an electric machine (3) is connected, the machine having three stator windings (L1, L2, L3), wherein a switchable connection (4) is provided between the high-voltage potentials (HV+, HV-) of the two inverters (2.1, 2.2) which are connected to a battery (5), wherein a disconnecting element (S-drive) is arranged between the battery (5) and one of the inverters (2.1, 2.2) and/or between the two inverters (2.1, 2.2) in one of the two high-voltage potentials (HV+, HV-) of the switchable connection (4), characterized in that a connection point is provided on one side of each stator winding (L1, L2, L3) for connection to a DC charging station (12) or to an AC charging station (14). L3) is brought out of the double inverter (1) and a switching element (S_DC_800_P) is arranged for connecting the positive high-voltage potential (HV+) to a positive terminal (DC_P) for the DC charging station (12), wherein a switching element (S_DC_N) is arranged for connecting the negative high-voltage potential (HV-) to a negative terminal (DC_N) for the DC charging station (12), wherein two switching elements (S_AC_L1, S_AC_L2) are arranged for connecting each of a phase terminal (U, V, W) for an AC charging station (14) to each of a terminal point of one of the stator windings (L1, L2, L3), wherein the positive terminal (DC_P) with one of these phase terminals (U, V, W) and the negative terminal (DC_N) with the other of these phase terminals (U, V, W) each connect to a common pin of a connector for optional connection of the DC charging station (12) and the AC charging station (14) is listed.
  2. Dual inverter (1) comprising two inverters (2.1, 2.2), each comprising three half-bridges made of semiconductor material tern (S1 to S12), each with three phase connections, between which an electric machine (3) is connected, the machine having three stator windings (L1, L2, L3), wherein a switchable connection (4) is provided between the high-voltage potentials (HV+, HV-) of the two inverters (2.1, 2.2) which are connected to a battery (5), wherein a disconnecting element (S-Fahren) is arranged between the battery (5) and one of the inverters (2.1, 2.2) and/or between the two inverters (2.1, 2.2) in one of the two high-voltage potentials (HV+, HV-) of the switchable connection (4), characterized in that for connection to a DC charging station (12) or to an AC charging station (14) a connection point is brought out of the double inverter (1) on one side of each stator winding (L1, L2, L3) and a switching element (S_DC_800_P) a switching element (S_DC_400_P) is arranged for connecting the positive high-voltage potential (HV+) to a positive terminal (DC_P) for a DC charging station (12), wherein a switching element (S_DC_400_P) is arranged for connecting one of the terminal points of the stator windings (L1, L2, L3) to the positive terminal (DC_P) for the DC charging station (12), wherein a switching element (S_DC_N) is arranged for connecting the negative high-voltage potential (HV-) to a negative terminal (DC_N) for the DC charging station (12), wherein a switching element (S_AC_L1, S_AC_L2, S_AC_L3) is arranged for connecting each phase terminal (U, V, W) for an AC charging station (14) to each terminal point of one of the stator windings (L1, L2, L3), and a switching element (S_DC_400_N) is arranged for connecting another of the terminal points of the stator windings (L1, L2, L3) is arranged with the negative terminal (DC_N) for the DC charging station (12).
  3. Double inverter (1) according to Claim 1 or 2 , characterized in that a battery main contactor (S_Main_P, S_Main_N) is arranged for direct connection between the battery (5) and one of the inverters (2.1, 2.2) in both high-voltage potentials (HV+, HV-), wherein an isolating DC/DC converter (6) is arranged between the battery (5) and this inverter (2.1, 2.2) for alternative or parallel indirect connection.
  4. Dual inverter (1) according to one of the preceding claims, characterized in that the inverters (2.1, 2.2) are each configured as a B6 bridge with three upper semiconductor switches (S1, S3, S5, S7, S9, S11) and three lower semiconductor switches (S2, S4, S6, S8, S10, S12).
  5. Dual inverter (1) according to one of the preceding claims, characterized in that an intermediate circuit capacitor (C1) is arranged between the high voltage potentials (HV+, HV-) of the battery-side inverter (2.1) and the isolating DC/DC converter (6).
  6. A method for charging a battery (5) of a high-voltage system (10), comprising a dual inverter (1) according to one of the preceding claims at a DC charging station (12), characterized in that when an output voltage (U EVSE ) of the DC charging station (12) is lower than a battery voltage (U Batt ), the switching element (S_DC_800_P) for disconnecting the positive high-voltage potential (HV+) from the positive terminal (DC_P) for the DC charging station (12) is or becomes open, while the switching elements (S_DC_400_P, S_DC_N) for connecting one of the terminal points of the stator windings (L1, L2, L3) to the positive terminal (DC_P) and for connecting the negative high-voltage potential (HV-) to a negative terminal (DC_N) and the battery main contactors (S_Main_P, S_Main_N) are or become closed, wherein at least two of the upper or lower semiconductor switches (S7 to S12) are in one of the high-voltage potentials (HV+, HV-) of the inverter (2.1, 2.2), from which the connection points are brought out, are closed to form a star point, wherein at least one of the lower or upper semiconductor switches (S1 to S6) of the other inverter (2.1, 2.2) is operated in a switching manner in the other high-voltage potential (HV-, HV+).

Description

The invention relates to a double inverter according to the preamble of claim 1 and claim 2, and to a method for charging a battery of a high-voltage system according to the preamble of claim 6. DE 10 2022 132 370 A1 Describes a device that enables a two-stage inverter to switch between modes. The device comprises a first inverter unit, a second inverter unit, a load connected between the first and second inverter units, a mode switching unit connected between the load and the second inverter unit, and a control unit designed to control the load in a single-stage inverter mode or a two-stage inverter mode by performing a control operation that turns the mode switching unit on or off. The genre-defining script DE 10 2023 212 202 A1 This concerns the technical field of controlling an electric motor. The electric drive system comprises a pair of inverters and an open-winding electric motor, with each end of one phase winding of the electric motor connected to an output of a corresponding inverter. The electric drive system is equipped with a boost charging mode, allowing both driving and charging operation to be performed via the two inverters. From the KR 102 512 192 B1 A multi-charge inverter system is known that comprises two inverter units between which a motor with its windings is connected. Different charging modes can thus be implemented via an AC charging port, a DC charging port, and a mode switching unit. The US 2023 / 0 202 320 A1 Disclosure reveals an on-board charger for the battery of an electric vehicle. The electric vehicle comprises an AC motor and an inverter drive for it. The on-board charger includes an integrated active filter rectifier coupled to a DC/DC converter. The integrated active filter rectifier is configured to utilize at least one phase inductance of the AC motor and at least one branch of the inverter drive for power factor correction. The invention is based on the objective of providing a novel double inverter and a novel method for charging a battery of a high-voltage system. The problem is solved according to the invention by a double inverter with the features of claim 1, claim 2 and a method for charging a battery of a high-voltage system with the features of claim 6. Advantageous embodiments of the invention are the subject of the dependent claims. A dual inverter is proposed, comprising two inverters, each comprising three half-bridges made of semiconductor switches, each with three phase connections, between which an electric machine is connected having three stator windings. A switchable connection is provided between the high-voltage potentials of the two inverters, which are connected to a battery. A disconnecting element is arranged between the battery and one of the inverters and/or between the two inverters at one of the two high-voltage potentials of the connection. According to the invention, a connection point is provided on one side of each stator winding of the dual inverter for connection to a DC charging station or an AC charging station. According to the invention, in a first embodiment, a switching element is arranged for connecting the positive high-voltage potential to a positive terminal for the DC charging station, wherein a switching element is arranged for connecting the negative high-voltage potential to a negative terminal for the DC charging station, wherein two switching elements are arranged for connecting each of a phase terminal for an AC charging station to each of a terminal point of one of the stator windings, wherein the positive terminal is connected to one of these phase terminals and the negative terminal to the other of these phase terminals, each to a common pin of a connector for selective connection of the DC charging station and the AC charging station. According to the invention, in a second embodiment, a switching element is arranged for connecting the positive high-voltage potential to a positive terminal for a DC charging station, wherein a switching element is arranged for connecting one of the connection points of the stator windings to the positive terminal for the DC charging station, wherein a switching element is arranged for connecting the negative high-voltage potential to a negative terminal for the DC charging station, and wherein a switching element is arranged for connecting each phase terminal for an AC charging station to each connection point of one of the stator windings. Furthermore, a switching element is arranged for The connection of another of the stator winding connection points is arranged with the negative terminal for the DC charging station. In one embodiment, a main battery contactor is arranged between the battery and one of the inverters in both high-voltage potentials for direct connection, wherein an isolating DC/DC converter is arranged between the battery and this inverter for alternative or parallel indirect connection. In one embodiment, the inverters are each configured as a B6 bridge with t