Hybrid vehicle systems and methods for controlling torque and diagnosing torque constraints

Patent metadata

Field	Value
Publication number	US-2025249888-A1
Application number	US-202418432642-A
Country	US
Kind code	A1
Filing date	Feb 5, 2024
Priority date	Feb 5, 2024
Publication date	Aug 7, 2025
Grant date	—

Abstract

A system for determining a secondary axle torque of a hybrid vehicle is disclosed. The hybrid vehicle includes a primary axle driven by an engine and a secondary axle driven by an electric motor. The system includes one or more sensors configured to detect a driver torque request, and a control module in communication with the one or more sensors. The control module is configured to receive data from the one or more sensors indicative of the driver torque request, calculate a primary torque target for the primary axle based on an optimal engine torque, calculate a secondary torque target for the secondary axle based on the calculated primary torque target and the driver torque request, and generate a secondary torque command to drive the secondary axle based on the calculated secondary torque target and the driver torque request. Other example systems and methods are also disclosed.

First claim

What is claimed is:

1 . A vehicle system for determining a secondary axle torque of a hybrid vehicle, the hybrid vehicle including a primary axle driven by an engine and a secondary axle driven by an electric motor, the vehicle system comprising:
one or more sensors configured to detect a driver torque request; and a control module in communication with the one or more sensors, the control module configured to:
receive data from the one or more sensors indicative of the driver torque request;
calculate a primary torque target for the primary axle based on an optimal engine torque;
calculate a secondary torque target for the secondary axle based on the calculated primary torque target and the driver torque request; and
generate a secondary torque command to drive the secondary axle based on the calculated secondary torque target and the driver torque request.

2 . The vehicle system of claim 1 , wherein the control module is configured to:
determine a secondary torque limit for the secondary axle; and calculate the secondary torque target based on the calculated primary torque target, the driver torque request, and the secondary torque limit.

3 . The vehicle system of claim 2 , wherein the control module is configured to set the secondary torque target to the secondary torque limit.

4 . The vehicle system of claim 2 , wherein the control module is configured to receive a plurality of conditions associated with the hybrid vehicle and determine the secondary torque limit based on the received conditions.

5 . The vehicle system of claim 4 , wherein the plurality of conditions include a state of charge of a battery associated with the electric motor, a speed of the hybrid vehicle, and a torque limit of the electric motor.

6 . The vehicle system of claim 1 , wherein the control module is configured to generate a primary torque command to drive the primary axle.

7 . The vehicle system of claim 1 , wherein the control module is configured to calculate the primary torque target for the primary axle based on the optimal engine torque and a condition associated with a transmission connected to the engine.

8 . A hybrid vehicle comprising the vehicle system of claim 1 .

9 . A method for determining a secondary axle torque of a hybrid vehicle, the hybrid vehicle including a primary axle driven by an engine and a secondary axle driven by an electric motor, the method comprising:
receiving data from one or more sensors indicative of a driver torque request; calculating a primary torque target for the primary axle based on an optimal engine torque; calculating a secondary torque target for the secondary axle based on the calculated primary torque target and the driver torque request; and generating a secondary torque command to drive the secondary axle based on the calculated secondary torque target and the driver torque request.

10 . The method of claim 9 , wherein:
the method further comprises determining a secondary torque limit for the secondary axle; and calculating the secondary torque target includes the secondary torque target for the secondary axle based on the calculated primary torque target, the driver torque request, and the secondary torque limit.

11 . The method of claim 10 , further comprising setting the secondary torque target to the secondary torque limit.

12 . The method of claim 10 , wherein:
the method further comprises receiving a plurality of conditions associated with the hybrid vehicle; and determining the secondary torque limit includes determining the secondary torque limit based on the received conditions.

13 . The method of claim 12 , wherein the plurality of conditions include a state of charge of a battery associated with the electric motor, a speed of the hybrid vehicle, and a torque limit of the electric motor.

14 . The method of claim 9 , further comprising generating a primary torque command to drive the primary axle.

15 . A method for diagnosing a reason for being unable to use an electric motor to drive a secondary axle of a hybrid vehicle while maintaining an engine for a primary axle of the hybrid vehicle at a defined torque range during catalyst light-off (CLO), the method comprising:
determining whether a secondary torque request for the secondary axle is constrained; in response to the secondary torque request being constrained, determining whether a fault condition is present; in response to determining the fault condition is not present, calculating an expected secondary torque limit for the secondary axle; determining whether an actual secondary torque limit for the secondary axle is greater than the expected secondary torque limit for the secondary axle; and in response to the actual secondary torque limit being less than the expected secondary torque limit, generating an emissions alert indicating CLO diagnostics to execute normally.

16 . The method of claim 15 , wherein determining whether the secondary torque request is constrained includes:
determining whether the secondary torque request is different than a secondary torque target for the secondary axle for a defined set of reasons; and in response to the secondary torque request being different than the secondary torque target for a reason not found in the defined set of reasons, determining the secondary torque request is constrained due to a secondary torque limit.

17 . The method of claim 16 , wherein:
the fault condition is a first fault condition; and the method further comprises, in response to the secondary torque request being different than the secondary torque target for one of the defined set of reasons, determining whether a second fault condition is present.

18 . The method of claim 17 , further comprising, in response to determining the second fault condition is not present, generating an emissions alert indicating CLO diagnostics is paused with an emission penalty.

19 . The method of claim 17 , further comprising, in response to determining the second fault condition is present, generating the emissions alert indicating CLO diagnostics is paused without an emission penalty.

20 . The method of claim 15 , further comprising, in response to determining the fault condition is present, generating an emissions alert indicating CLO diagnostics is paused without an emission penalty.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Gwidt J Michael
• Hu Yiran
• Kim Kee Y
• Patel Krunal P
• Kurian Sandhu Kurian
• Bush Matthew Gabriel
• Dimoski Daniel S
• Smitsky Brandon Michael
• Zettel Andrew M

Classifications

• B60W20/50 Primary

  Control strategies for responding to system failures, e.g. for fault diagnosis, failsafe operation or limp mode · CPC title

• B60W20/16

  for reducing engine exhaust emissions · CPC title

• B60W20/40

  Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers {(power-up or power-down of the driveline B60W30/192)} · CPC title

• B60W30/02

  Control of vehicle driving stability · CPC title

• B60W20/13

  in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion · CPC title