Systems and methods for battery regeneration based on engine loading

Patent metadata

Field	Value
Publication number	US-2016111990-A1
Application number	US-201414518582-A
Country	US
Kind code	A1
Filing date	Oct 20, 2014
Priority date	Oct 20, 2014
Publication date	Apr 21, 2016
Grant date	—

Abstract

An alternator voltage may be controlled based on a proportional gain scheduling in response to an engine load of an internal combustion engine and/or a state of charge (SOC) deviation for a battery based on a target SOC of the battery and an actual SOC of the battery. The alternator voltage may be a voltage less than a current battery voltage under high engine loads to enable the battery to power an accessory system and the alternator voltage may be a voltage greater than a voltage of the battery under low engine loads or engine loads less than high engine loads to enable the alternator to charge the battery.

First claim

What is claimed is:

1 . A method, comprising:
determining an engine load of an internal combustion engine mechanically coupled to an alternator, wherein a battery is electrically coupled to the alternator; determining a state of charge (SOC) deviation for the battery based on a target SOC of the battery and an actual SOC of the battery; scheduling a proportional gain in response to at least one of the engine load and the SOC deviation; and providing, with a controller, an alternator voltage command to the alternator based on the proportional gain.

2 . The method of claim 1 , further comprising:
scheduling the proportional gain further in response to at least one further engine operating condition, the at least one further engine operating condition comprising an engine operating condition that is not the engine load.

3 . The method of claim 1 , further comprising:
determining an alternator power demand based on at least one of the proportional gain and the SOC deviation; determining an alternator voltage demand based on a conversion of the alternator power demand; and further providing the alternator voltage command to the alternator based on the alternator voltage demand.

4 . The method of claim 3 , further comprising:
determining the alternator power demand by applying a filter to the proportional gain.

5 . The method of claim 3 , wherein the determining the alternator power demand further comprises minimizing a SOC deviation.

6 . The method of claim 3 , further comprising:
adjusting the alternator power demand by applying a hysteresis, smoothing the alternator power demand, and applying a power limiter; and further determining the alternator voltage demand in response to the adjusted alternator power demand.

7 . The method of claim 3 , further comprising:
determining a limited alternator voltage demand based on at least one of a protection condition and a saturation limit, and further determining the alternator voltage command in response to the limited alternator voltage demand.

8 . The method of claim 7 , wherein the protection condition includes at least one condition selected from the conditions consisting of a current engine speed being less than a threshold, a SOC amount difference from a nominal SOC amount, and a SOC sensor signal being lost.

9 . The method of claim 1 , wherein the providing the alternator voltage command to the alternator further includes providing a low voltage command in response to the engine load being above a high threshold value, wherein the low voltage command causes the battery to power an accessory system.

10 . The method of claim 9 , wherein the providing the alternator voltage command to the alternator further includes providing a high voltage command in response to the engine load being equal to or below a high threshold value, wherein the high voltage command causes the alternator to charge the battery.

11 . A system, comprising:
a start-stop vehicle including an internal combustion engine mechanically coupled to an alternator, an electrical energy storage device electrically coupled to the alternator, and a controller in electrical communication with the internal combustion engine, the alternator, the electrical energy storage device, and one or more vehicle sensors operable to provide signals indicating conditions of the start-stop vehicle, wherein the controller is structured to:
interpret an engine load of the internal combustion engine;
determine a state of charge (SOC) error of the battery based on a target SOC of the battery and an actual SOC of the battery;
determine a proportional gain as a function of at least one of the engine load and the SOC error; and
provide an alternator voltage command to the alternator based on the proportional gain.

12 . The system of claim 11 , wherein the proportional gain is further determined in response to at least one further engine operating condition, the at least one further engine operating condition comprising an engine operating condition that is not the engine load.

13 . The system of claim 11 , wherein the engine load comprises a net brake torque.

14 . The system of claim 11 , further comprising operating a closed loop controller to determine at least one of the SOC error and the proportional gain.

15 . The system of claim 11 , wherein the controller is further structured to:
adjust the SOC error based on at least one of a present vehicle speed, a temperature of the battery, a state of health (SOH) of the battery, a start-stop vehicle power demand, and an integrated SOC deviation of the battery over time, wherein at least one of the proportional gain and the alternator voltage command is further based on the adjusted SOC error.

16 . The system of claim 11 , wherein the alternator voltage command comprises a high voltage command to enable the alternator to charge the battery when the engine load being equal to or less than a high threshold value.

17 . The system of claim 16 , wherein the alternator voltage command comprises a low voltage command to enable the battery to power accessories in response to the engine load being greater than the high threshold value.

18 . An apparatus, comprising:
an electronic controller in operative communication with a plurality of sensors operable to provide signals indicating conditions of a system, the system including an engine, an alternator operationally coupled to the engine, and a battery electrically coupled to the alternator, wherein the electronic controller includes:
a state of charge (SOC) error determination module structured to determine a SOC error of the battery;
a gain scheduling module structured to determine a proportional gain in response to an engine load and the SOC error; and
an alternator voltage control module structured to provide the alternator with an alternator voltage command based on the proportional gain.

19 . The apparatus of claim 18 , further comprising:
an alternator power demand determination module structured to determine an alternator power demand based on the proportional gain and the SOC error; a power to voltage conversion module structured to convert the alternator power demand to an alternator voltage demand; and an alternator voltage limiting module structured to limit the alternator voltage demand, wherein the alternator voltage control module is further structured to provide the alternator voltage command further based on the limited alternator voltage.

20 . The apparatus of claim 19 , wherein the alternator voltage demand is limited based on at least one of a speed of the engine, a SOC of the battery, a saturation limit of the battery, and a temperature of the battery.

21 . The apparatus of claim 18 , wherein the alternator voltage command causes the alternator to either charge the battery or power one or more accessories.

22 . The apparatus of claim 18 , wherein the gain scheduling module is further structured to determine the proportional gain further in response to at least one further engine operating condition, the at least one further engine operating condition comprising an engine operating condition that is not the engine load.

23 . The apparatus of claim 18 , wherein the alternator voltage command comprises a low voltage command when the engine load is high, the low voltage command being a voltage less than a current battery voltage to enable the battery to power an accessory system.

Assignees

• Cummins Inc

Inventors

• Books Martin T
• Sujan Vivek A
• Muralidhar Praveen C

Classifications

• F02N11/0862

  characterised by the electrical power supply means, e.g. battery · CPC title

• H02P9/48

  Arrangements for obtaining a constant output value at varying speed of the generator, e.g. on vehicle (H02P9/04 - H02P9/46 take precedence) · CPC title

• H02P9/008 Primary

  wherein the generator is controlled by the requirements of the prime mover · CPC title

• Y02T10/7072

  Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors · CPC title

• Y02T10/62

  Hybrid vehicles · CPC title