# US 12,191,688 B2 · Systems and methods for increasing degraded torque availability > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,191,688 B2 - Document ID: US12191688B2 - Status: Granted - Kind: B2 - Application number: 17/658,339 - Filed: 2022-04-07 - Published: 2022-10-13 - Granted: 2025-01-07 - Earliest claimed: 2021-04-08 - Assignees: NXP B.V. - Applicants: NXP B.V. - Inventors: Antoine Fabien Dubois; Erik Santiago - Web page: https://patentgrep.com/patent/US12191688B2 ## CPC - H02J 7/663: {using battery or load disconnect circuits (H02J9/002 takes precedence)} - B60L 3/0023: {Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train} - B60L 3/0046: {relating to electric energy storage systems, e.g. batteries or capacitors} - B60L 50/50: using propulsion power supplied by batteries or fuel cells - H02J 7/1423: {with multiple batteries} - H02J 7/342: {The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging (with circuits for polarity protection H02J7/68)} - H02J 7/90: Regulation of charging or discharging current or voltage - H02P 29/028: the motor continuing operation despite the fault condition, e.g. eliminating, compensating for or remedying the fault - B60L 3/003: {relating to inverters} - B60L 3/0092: {with use of redundant elements for safety purposes} - B60L 2210/10: DC to DC converters - B60L 2210/12: Buck converters - B60L 2210/14: Boost converters - B60L 2260/26: Transition between different drive modes - B60L 2270/20: Inrush current reduction, i.e. avoiding high currents when connecting the battery - H02J 7/62: against overcurrent - H02J 7/94: in response to battery current - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES - H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS ## Abstract In a battery management system, during a pre-charge mode, a first contactor is closed to provide a pre-charge current path from a low voltage battery supply node through a DCDC converter and through the first contactor to pre-charge a capacitor of an inverter for an electric motor. During a drive mode following the pre-charge mode, the first contactor is opened and a second contactor is closed to provide a drive mode current path from a high voltage battery supply node through the second contactor to the inverter to power the electric motor. In response to detecting an open fault in the second contactor during the drive mode, a limp mode is entered. During the limp mode, the first contactor is closed to provide a limp mode current path from the high voltage battery supply node through the first contactor to the inverter to power the electric motor. ## Claims ### Claim 1 A battery management circuit for use in an electric vehicle and comprising: a first output configured to provide a first control signal to a control input of a first contactor having a first terminal coupled to a high voltage battery supply node and a second terminal coupled to a first terminal of a direct current to direct current, DCDC, converter, wherein a second terminal of the DCDC converter is coupled to a low voltage battery supply node; a second output configured to provide a second control signal to a control input of a second contactor having a first terminal coupled to the high voltage battery supply node and a second terminal coupled to a first terminal of an inverter for an electric motor, wherein the inverter includes a capacitor; and a third output configured to provide a third control signal to a control input of a third contactor, wherein the third contactor has a first terminal coupled to the second terminal of the first contactor and to the first terminal of the DCDC converter, and has a second terminal coupled to the second terminal of the second contactor and to the first terminal of the inverter; wherein the battery management circuit is configured to: during a pre-charge mode, provide a pre-charge current path from the low voltage battery supply node, through the DCDC converter and the third contactor, to the inverter to pre-charge the capacitor in the inverter; during a drive mode, provide a primary current path from the high voltage battery supply node, through the second contactor, to the inverter to power the electric motor; and during the drive mode, in response to detecting a fault associated with the second contactor in which the primary current path becomes unavailable, enter a limp mode to provide a secondary current path from the high voltage battery supply node, through the third contactor, to the inverter to power the electric motor. ### Claim 2 (depends on 1) The battery management circuit of claim 1, configured to, during the drive mode, provide a second primary current path from the high voltage battery node through the first contactor to the DCDC converter. ### Claim 3 (depends on 2) The battery management circuit of claim 2, configured to, during the drive mode, prior to entering the limp mode, negate the third control signal to open the third contactor. ### Claim 4 (depends on 2) The battery management circuit of claim 2, wherein the DCDC converter is characterized as a two-way converter, wherein during the drive mode, the DCDC converter operates in a first direction, and, during the pre-charge mode, the DCDC converter operates in a second direction, opposite the first direction. ### Claim 5 (depends on 1) The battery management circuit of claim 1, configured to: during the pre-charge mode, assert the third control signal to close the third contactor and negate the first and second control signals to open the first and second contactors. ### Claim 6 (depends on 5) The battery management circuit of claim 5, configured to: during the drive mode to provide the primary current path, assert the first and second control signals to close the first and second contactors respectively and negate the third control signal to open the third contactor. ### Claim 7 (depends on 6) The battery management circuit of claim 6, configured to: upon entering the limp mode to provide the secondary current path, assert the third control signal to close the third contactor. ### Claim 8 (depends on 1) The battery management circuit of claim 1, further comprising: a fourth output configured to provide a fourth control signal to control inputs of a fourth and fifth contactor, coupled in parallel to each other, between a second high voltage battery supply node and each of the first terminals of the DCDC converter and the inverter. ### Claim 9 (depends on 8) The battery management circuit of claim 8, configured to assert the fourth control signal to close each of the fourth and fifth contactors during the pre-charge mode, the drive mode, and the limp mode. ### Claim 10 A method comprising: during a pre-charge mode, closing a first contactor to provide a pre-charge current path from a low voltage battery supply node through a DCDC converter and through the first contactor to pre-charge a capacitor of an inverter for an electric motor; during a drive mode following the pre-charge mode, opening the first contactor and closing a second contactor to provide a drive mode current path from a high voltage battery supply node through the second contactor to the inverter to power the electric motor; in response to detecting an open fault in the second contactor during the drive mode, entering a limp mode; and during the limp mode, closing the first contactor to provide a limp mode current path from the high voltage battery supply node through the first contactor to the inverter to power the electric motor. ### Claim 11 (depends on 10) The method of claim 10, wherein during the drive mode, the method further comprises closing a third contactor to provide a second drive mode current path from the high voltage battery node through the third contactor to the DCDC converter. ### Claim 12 An electric vehicle comprising: a high voltage battery supply node; a low voltage battery supply node, wherein the high voltage battery supply node supplies a positive voltage that is greater than a positive voltage supplied by the low voltage battery supply node; a direct current to direct current (DCDC) converter; an inverter for an electric motor, the inverter having a capacitor; a first contactor having a first terminal coupled to the high voltage battery supply node and a second terminal coupled to a first terminal of the DCDC converter, wherein a second terminal of the DCDC converter is coupled to the low voltage battery supply node; a second contactor having a first terminal coupled to the high voltage battery supply node and a second terminal coupled to a first terminal of the inverter; a third contactor having a first terminal coupled to the second terminal of the first contactor and the first terminal of the DCDC converter, and having a second terminal coupled to the second terminal of the second contactor and the first terminal of the inverter; and a battery management circuit configured to: during a pre-charge mode, provide a pre-charge current path from the low voltage battery supply node, through the DCDC converter and the third contactor, to the inverter to pre-charge the capacitor in the inverter; during a drive mode, provide a drive mode current path from the high voltage battery supply node, through the second contactor, to the inverter to power the electric motor; and during the drive mode, in response to detecting a fault corresponding to the second contactor in which the drive mode current path becomes unavailable, enter a limp mode to provide a limp mode current path from the high voltage battery supply node, through the third contactor, to the inverter to power the electric motor. ### Claim 13 (depends on 12) The electric vehicle of claim 12, configured to, during the drive mode, provide a second drive mode current path from the high voltage battery node through the first contactor to the DCDC converter. ### Claim 14 (depends on 13) The electric vehicle of claim 13, wherein: the DCDC converter is a two-way converter, during the drive mode, the DCDC converter operates in a first direction, and during the pre-charge mode, the DCDC converter operates in a second direction, opposite the first direction. ### Claim 15 (depends on 12) The electric vehicle of claim 12, wherein the battery management circuit is configured to: during the pre-charge mode, close the third contactor and open the first and second contactors. ### Claim 16 (depends on 15) The electric vehicle of claim 15, wherein the battery management circuit is configured to: during the drive mode to provide the drive mode current path, close the first and second contactors and open the third contactor. ### Claim 17 (depends on 16) The electric vehicle of claim 16, wherein the battery management circuit is configured to: upon entering the limp mode to provide the limp mode current path, close the third contactor. ### Claim 18 (depends on 12) The electric vehicle of claim 12, further comprising: a fourth contactor and a fifth contactor, coupled in parallel to each other, between a second high voltage battery supply node and each of the first terminals of the DCDC converter and the inverter. ### Claim 19 (depends on 18) The electric vehicle of claim 18, wherein the battery management circuit is configured to close each of the fourth and fifth contactors during the pre-charge mode, the drive mode, and the limp mode. ### Claim 20 (depends on 12) The electric vehicle of claim 12, wherein the electric vehicle is characterized as one of a full electric vehicle or a hybrid electric vehicle.