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CN-112297949-B - Predictive control for energy storage management in an electric vehicle

CN112297949BCN 112297949 BCN112297949 BCN 112297949BCN-112297949-B

Abstract

The invention provides predictive control for energy storage management in an electric vehicle, and in particular, a method of controlling energy flow in an electric vehicle by a controller, the method including receiving driver information, road information, and environmental information associated with the electric vehicle. The method further includes predicting high and low voltage energy demands of the electric vehicle based on the received information. Based on the predicted high-voltage energy demand and the predicted low-voltage energy demand, the method includes operating a DC-to-DC converter to control energy flow between a high-voltage energy storage device, a low-voltage energy storage device, and a plurality of low-voltage accessory loads in the electric vehicle.

Inventors

  • TANG JUN
  • LIU BIN

Assignees

  • 康明斯公司
  • 康明斯公司

Dates

Publication Date
20260421
Application Date
20190801
Priority Date
20190801

Claims (18)

  1. 1. A method of controlling energy flow in an electric vehicle, the method comprising the steps of: Receiving, by a controller, information associated with the electric vehicle, the information including driver information, road information, and environmental information; predicting, by the controller, a high voltage, i.e., HV, energy demand and a low voltage, i.e., LV, energy demand of the electric vehicle based on the information, and Operating a direct current to direct current converter, i.e. a DC/DC converter, by the controller based on the predicted HV energy demand and the predicted LV energy demand to control energy flow between the HV energy storage device, the LV energy storage device and a plurality of LV accessory loads in the electric vehicle, The method further comprises the steps of determining a HV state of charge (HV SOC) of the HV energy storage device and a LV SOC of the LV energy storage device, Wherein the HV SOC and the predicted HV energy demand are less than a maximum HV SOC, and operating the DC/DC converter further comprises the steps of: Controlling the DC/DC converter to disable energy flow between the HV energy storage device and the LV energy storage device and between the HV energy storage device and the plurality of LV accessory loads, Wherein the LV SOC and the predicted LV energy demand are greater than or equal to a minimum LV SOC, and operating the DC/DC converter further comprises the steps of: The DC/DC converter is controlled to enable energy flow between the LV energy storage device and the plurality of LV accessory loads.
  2. 2. The method of claim 1, wherein the LV SOC and the predicted LV energy demand are less than a minimum LV SOC, the HV SOC and the predicted HV energy demand are less than a minimum HV SOC, and operating the DC/DC converter further comprises the steps of: controlling the DC/DC converter to enable energy flow between the LV energy storage device and the plurality of LV accessory loads, and One or more of the plurality of LV accessory loads are turned off according to a priority rule.
  3. 3. The method according to claim 1, wherein: when the HV SOC and the predicted HV energy demand are greater than or equal to a maximum HV SOC, and When the HV SOC and the predicted HV energy demand are less than a maximum HV SOC, the LV SOC and the predicted LV energy demand are less than a minimum LV SOC, and the HV SOC and the predicted HV energy demand are greater than or equal to a minimum HV SOC, Operating the DC/DC converter further includes the step of controlling the DC/DC converter to enable energy flow from the HV energy storage device and to receive input from the HV energy storage device.
  4. 4. A method according to claim 3, wherein the input from the HV energy storage device and the LV SOC and the predicted LV energy demand are greater than or equal to a maximum LV SOC, and operating the DC/DC converter further comprises the steps of: The DC/DC converter is controlled to enable energy flow between the HV energy storage device and the plurality of LV accessory loads and between the LV energy storage device and the plurality of LV accessory loads.
  5. 5. A method according to claim 3, wherein the input from the HV energy storage device and the LV SOC and the predicted LV energy demand are less than a maximum LV SOC.
  6. 6. The method of claim 5, wherein the input from the HV energy storage device is greater than or equal to the predicted LV energy demand, and operating the DC/DC converter further comprises the steps of: The DC/DC converter is controlled to enable energy flow between the HV energy storage device and the LV energy storage device and between the HV energy storage device and the plurality of LV accessory loads.
  7. 7. The method of claim 5, wherein the input from the HV energy storage device is less than the predicted LV energy demand, the value of the LV SOC minus a minimum LV SOC and the input from the HV energy storage device are greater than or equal to the predicted LV energy demand, and operating the DC/DC converter further comprises the steps of: The DC/DC converter is controlled to enable energy flow between the HV energy storage device and the LV energy storage device and between the HV energy storage device and the plurality of LV accessory loads.
  8. 8. The method of claim 5, wherein the input from the HV energy storage device is less than the predicted LV energy demand, the value of the LV SOC minus a minimum LV SOC and the input from the HV energy storage device are less than the predicted LV energy demand, and operating the DC/DC converter further comprises the steps of: Controlling the DC/DC converter to enable energy flow between the HV energy storage device and the plurality of LV accessory loads and between the LV energy storage device and the plurality of LV accessory loads, and One or more of the plurality of LV accessory loads are turned off according to a priority rule.
  9. 9. The method of claim 1 wherein predicting the HV energy demand and the LV energy demand comprises the step of aggregating the information to predict the HV energy demand and the LV energy demand.
  10. 10. A controller for controlling energy flow in an electric vehicle, the controller comprising: Processor, and A memory comprising instructions that when executed by the processor cause the controller to: receiving information associated with the electric vehicle, the information including driver information, road information, and environmental information; Predicting a high voltage, i.e., HV, energy demand and a low voltage, i.e., LV, energy demand of the electric vehicle based on the information, and Operating a direct current to direct current converter, i.e. a DC/DC converter, based on the predicted HV energy demand and the predicted LV energy demand, to control energy flow between a HV energy storage device, a LV energy storage device and a plurality of LV accessory loads in the electric vehicle, Wherein the instructions, when executed by the processor, further cause the controller to determine an HV state of charge of the HV energy storage device, i.e., an HV SOC, and an LV SOC of the LV energy storage device, Wherein the HV SOC and the predicted HV energy demand are less than a maximum HV SOC, and the instructions, when executed by the processor, further cause the controller to: Controlling the DC/DC converter to disable energy flow between the HV energy storage device and the LV energy storage device and between the HV energy storage device and the plurality of LV accessory loads, Wherein the LV SOC and the predicted LV energy demand are greater than or equal to a minimum LV SOC, and the instructions when executed by the processor further cause the controller to: The DC/DC converter is controlled to enable energy flow between the LV energy storage device and the plurality of LV accessory loads.
  11. 11. The controller of claim 10, wherein the LV SOC and the predicted LV energy demand are less than a minimum LV SOC, the HV SOC and the predicted HV energy demand are less than a minimum HV SOC, and the instructions, when executed by the processor, further cause the controller to: controlling the DC/DC converter to enable energy flow between the LV energy storage device and the plurality of LV accessory loads, and One or more of the plurality of LV accessory loads are turned off according to a priority rule.
  12. 12. The controller of claim 10, wherein: when the HV SOC and the predicted HV energy demand are greater than or equal to a maximum HV SOC, and When the HV SOC and the predicted HV energy demand are less than a maximum HV SOC, the LV SOC and the predicted LV energy demand are less than a minimum LV SOC, and the HV SOC and the predicted HV energy demand are greater than or equal to a minimum HV SOC, The instructions, when executed by the processor, further cause the controller to control the DC/DC converter to enable energy flow from the HV energy storage device and receive input from the HV energy storage device.
  13. 13. The controller of claim 12, wherein the input from the HV energy storage device and the LV SOC and the predicted LV energy demand are greater than or equal to a maximum LV SOC, and the instructions when executed by the processor further cause the controller to: The DC/DC converter is controlled to enable energy flow between the HV energy storage device and the plurality of LV accessory loads and between the LV energy storage device and the plurality of LV accessory loads.
  14. 14. The controller of claim 12, wherein the input from the HV energy storage device and the LV SOC and the predicted LV energy demand are less than a maximum LV SOC.
  15. 15. The controller of claim 14, wherein the input from the HV energy storage device is greater than or equal to the predicted LV energy demand, and the instructions, when executed by the processor, further cause the controller to: The DC/DC converter is controlled to enable energy flow between the HV energy storage device and the LV energy storage device and between the HV energy storage device and the plurality of LV accessory loads.
  16. 16. The controller of claim 14, wherein the input from the HV energy storage is less than the predicted LV energy demand, the LV SOC minus a minimum LV SOC and the input from the HV energy storage are greater than or equal to the predicted LV energy demand, and the instructions, when executed by the processor, further cause the controller to: The DC/DC converter is controlled to enable energy flow between the HV energy storage device and the LV energy storage device and between the HV energy storage device and the plurality of LV accessory loads.
  17. 17. The controller of claim 14, wherein the input from the HV energy storage is less than the predicted LV energy demand, the LV SOC minus a minimum LV SOC and the input from the HV energy storage is less than the predicted LV energy demand, and the instructions, when executed by the processor, further cause the controller to: Controlling the DC/DC converter to enable energy flow between the HV energy storage device and the plurality of LV accessory loads and between the LV energy storage device and the plurality of LV accessory loads, and One or more of the plurality of accessory loads are turned off according to a priority rule.
  18. 18. The controller of claim 10, wherein the instructions that when executed by the processor predict the HV energy requirement and the LV energy requirement further comprise instructions that cause the controller to aggregate the information to predict the HV energy requirement and the LV energy requirement.

Description

Predictive control for energy storage management in an electric vehicle Technical Field The present disclosure relates generally to electric vehicles, and more particularly, to methods and systems for energy storage management in electric vehicles. Background In electric vehicles, the energy storage system typically includes a high voltage ("HV") energy storage device (e.g., a main battery) for powering a motor generator that drives the vehicle, and a low voltage ("LV") energy storage device (e.g., an auxiliary battery) for powering various electrical loads of the vehicle. Conventional energy storage management methods focus on controlling energy flow based on current energy demand and state of charge ("SOC") of an energy storage device. However, looking only at the current energy demand and SOC may limit the speed of energy input and output. For example, if large inputs or outputs exist that the system cannot consume, the HV and LV energy storage devices may overcharge and discharge. As a result, the energy storage device may suffer irreversible damage. In addition, HV and LV energy storage devices are typically managed separately without regard to the overall system. Energy cannot be easily recovered or provided on demand due to inefficient energy storage management, which can result in significant degradation of the electric vehicle's performance. There remains a need to develop more efficient management of the entire energy storage system by taking into account the effects of SOC and future energy demand requirements. This will also improve the overall safety, life and cost effectiveness of the electric vehicle. Disclosure of Invention According to an embodiment, the present disclosure provides a method of controlling energy flow in an electric vehicle by a controller. The method includes the step of receiving information associated with the electric vehicle, wherein the information includes driver information, road information, and environmental information. The method also includes predicting an HV energy demand and an LV energy demand of the electric vehicle based on the information. The method may aggregate information to predict HV energy demand and LV energy demand. Based on the predicted HV energy demand and the predicted LV energy demand, the method further includes operating the DC/DC converter to control energy flow between the HV energy storage device, the LV energy storage device, and the plurality of LV accessory loads in the electric vehicle. In one aspect, the method further includes determining an HV SOC of the HV energy storage device and an LV SOC of the LV energy storage device. In another aspect, operating the DC/DC converter when the HV SOC and the predicted HV energy demand are less than the maximum HV SOC includes controlling the DC/DC converter to disable energy flow between the HV energy storage device and the LV energy storage device and between the HV energy storage device and the plurality of LV accessory loads. In yet another aspect, operating the DC/DC converter when the LV SOC and the predicted LV energy demand are greater than or equal to the minimum LV SOC includes controlling the DC/DC converter to enable energy flow between the LV energy storage device and the plurality of LV accessory loads. In yet another aspect, when the LV SOC and the predicted LV energy demand are less than the minimum LV SOC and the HV SOC and the predicted HV energy demand are less than the minimum HV SOC, operating the DC/DC converter includes controlling the DC/DC converter to enable energy flow between the LV energy storage device and the plurality of LV accessory loads and to shut down one or more of the plurality of LV accessory loads according to the priority rules. In a further aspect, operating the DC/DC converter when the HV SOC and the predicted HV energy demand are greater than or equal to the maximum HV SOC and when the HV SOC and the predicted HV energy demand are less than the maximum HV SOC and the LV SOC and the predicted LV energy demand are less than the minimum LV SOC and the HV SOC and the predicted HV energy demand are greater than or equal to the minimum HV SOC includes controlling the DC/DC converter to enable energy flow from the HV energy storage device and to receive input from the HV energy storage device. In yet another aspect, operating the DC/DC converter when the input from the HV energy storage device and the LV SOC and the predicted LV energy demand are greater than or equal to the maximum LV SOC includes controlling the DC/DC converter to enable energy flow between the HV energy storage device and the plurality of LV accessory loads and between the LV energy storage device and the plurality of LV accessory loads. In another aspect, the input from the HV energy storage device and the LV SOC and the predicted LV energy demand are less than the maximum LV SOC. In yet another aspect, operating the DC/DC converter when the input from the HV energy storage device is g