Energy management system and method for a vehicle

Patent metadata

Field	Value
Publication number	US-9550434-B2
Application number	US-201514971415-A
Country	US
Kind code	B2
Filing date	Dec 16, 2015
Priority date	Dec 31, 2014
Publication date	Jan 24, 2017
Grant date	Jan 24, 2017

Abstract

The present invention relates to an energy management system including a motor, an inverter electrically connected to the motor, a DC-DC converter electrically connected to the inverter, a first energy storage unit electrically connected to a DC link of the inverter through the DC-DC converter, a second energy storage unit coupled to the inverter, and a control unit. The control unit is configured to control the distribution of electrical power from the first energy storage unit and the second energy storage unit to the inverter in dependence upon a predetermined power threshold.

First claim

What is claimed is:

1. An energy management system, comprising:
a motor;
an inverter electrically connected to the motor;
a DC-DC converter electrically connected to the inverter;
a first energy storage unit electrically connected to a DC link of the inverter through the DC-DC converter;
a second energy storage unit coupled to the inverter; and
a control unit configured to control the distribution of electrical power from the first energy storage unit and the second energy storage unit to the inverter in dependence upon a predetermined power threshold and
the control unit is configured to control the first energy storage unit to provide a first amount of power, the first amount of power being less than or equal to the power threshold and to control the second energy storage unit to provide a second amount of power, the second amount of power being the difference between a total amount of power requested and the power threshold.

2. The energy management system of claim 1 , wherein:
the system is deployed on one of an underground material transport vehicle, a package delivery vehicle (PDV), or an urban transit bus.

3. The energy management system of claim 1 , wherein:
at least one of the first energy storage unit or the second energy storage unit is a sodium metal-halide battery.

4. The energy management system of claim 1 , wherein:
the control unit is configured to control the distribution of electrical power from the first energy storage unit and the second energy storage unit in dependence upon one or more energy storage unit characteristics including state of charge, internal resistance, and terminal voltage.

5. The energy management system of claim 1 , wherein:
the control unit is configured to adjust the power threshold in dependence upon a temperature rise rate of the first energy storage unit.

6. The energy management system of claim 5 , wherein:
the control unit is configured to lower the power threshold when the temperature rise rate of the first energy storage unit exceeds a predetermined temperature rise rate.

7. The energy management system of claim 1 , wherein:
the control unit is configured to adjust the power threshold in response to a detected state of charge of the first energy storage unit.

8. A method for managing the distribution rate of electrical energy on an electric vehicle, comprising the steps of:
in response to a total power demand, controlling a first energy storage unit to provide a first amount of electrical energy to a motor, the first amount of electrical energy being equal to or less than a predetermined power threshold; and
controlling a second energy storage unit to provide a second amount of electrical energy to the motor, the second amount of electrical energy being the difference between the total power demand and the first amount of electrical energy provided to the motor by the first energy storage unit.

9. The method according to claim 8 , further comprising the step of:
adjusting the predetermined power threshold in response to a detected temperature rate rise of the first energy storage unit.

10. The method according to claim 9 , wherein:
adjusting the predetermined power threshold includes lowering the threshold amount when the temperature rate rise of the first energy storage unit exceeds a rate threshold.

11. The method according to claim 8 , wherein:
the electric vehicle is an underground material transport vehicle.

12. The method according to claim 8 , wherein:
at least one of the first energy storage unit or the second energy storage unit is a sodium metal-halide battery.

13. The method according to claim 8 , further comprising the step of:
adjusting the predetermined power threshold in response to a detected state of charge of the first energy storage unit.

14. A method of managing the distribution rate of electrical energy from an energy storage unit, the method comprising the steps of:
controlling a discharge of electrical energy from a cell operating using a first chemistry of the energy storage unit according to a first power split parameter;
at a first determined characteristic, controlling the discharge of electrical energy from the cell operating with a second chemistry of the energy storage unit according to a second power split parameter; and
at a second determined characteristic, controlling the discharge of electrical energy from the cell operating with the second chemistry according to a third power split parameter.

15. The method according to claim 14 , wherein:
the first characteristic is a first determined state of charge of the first chemistry cell.

16. The method according to claim 15 , wherein:
the second characteristic is a second determined state of charge of the first chemistry cell operating with the first chemistry.

17. The method according to claim 16 , wherein:
the second determined characteristic is a second determined depth of discharge of the cell operating with the first chemistry.

18. The method according to claim 14 , wherein:
the first characteristic is a first determined depth of discharge of the first chemistry cell.

19. The method according to claim 14 , wherein:
the energy storage unit is a sodium metal-halide battery.

Assignees

• Gen Electric

Inventors

• King Robert Dean
• Xiao Funian

Classifications

• H02P27/06

  using DC to AC converters or inverters (H02P27/05 takes precedence) · CPC title

• B60L58/20

  having different nominal voltages · CPC title

• B60L58/25

  by controlling the electric load · CPC title

• H02J7/34

  Parallel operation in networks using both storage and other DC sources, e.g. providing buffering (H02J7/14 takes precedence) · CPC title

• B60L50/51

  characterised by AC-motors · CPC title