Electric propulsion system for a vehicle

Patent metadata

Field	Value
Publication number	US-10449848-B2
Application number	US-201515544263-A
Country	US
Kind code	B2
Filing date	Jan 26, 2015
Priority date	Jan 26, 2015
Publication date	Oct 22, 2019
Grant date	Oct 22, 2019

Abstract

A vehicle provided with an electric propulsion system and a method for controlling the electric propulsion system are provided. The system includes a first Electrical Motor (EM 1 ) connected via first Electrical Connections (EC 1 ) to an on-board Energy Storage System (ESS 1 ) and drivingly connected to wheels. The system further includes a second Electrical Motor (EM 2 ) connected via second Electrical Connections (EC 2 ) to one or several electrical energy sources and drivingly connected to wheels. The system is controlled by an Electronic Control Unit (ECU) and the Electrical Motors (EM 1 , EM 2 ) are used in dependence of the State Of Charge (SOC) level in the first Energy Storage System (ESS 1 ) and the availability of electrical energy for the second Electrical Motor (EM 2 ). The ECU is programmed to include an energy transfer mode in which the use of the second Electric Motor (EM 2 ) for propulsive force is increased and the use of the first Electric Motor (EM 1 ) for regenerative breaking is increased when the State Of Charge (SOC) level in the first electrical Energy Storage System (ESS 1 ) is below a defined level and it is estimated that there is more electrical energy available for the second Electrical Motor (EM 2 ) than for the first Electrical Motor (EM 1 ).

First claim

The invention claimed is:

1. A vehicle, provided with an electric propulsion system comprising:
a first Electrical Motor (EM 1 ) for propulsion of the vehicle provided with first Electrical Connections (EC 1 ) designed to be connected to and powered by one or several electrical energy sources;
at least one driven wheel being drivingly connected to the first Electrical Motor (EM 1 );
a second Electrical Motor (EM 2 ) for propulsion of the vehicle provided with second Electrical Connections (EC 2 ) designed to be connected to and powered by one or several electrical energy sources;
at least one driven wheel being drivingly connected to the second Electrical Motor (EM 2 );
an on-board Energy Storage System (ESS 1 ) electrically connected to the first Electrical Motor (EM 1 ) via the first Electrical Connections (EC 1 ) in order to provide electrical power to the first Electrical Motor (EM 1 ); and
an Electronic Control Unit (ECU) programmed to control the electric propulsion system and the use of the first Electrical Motor (EM 1 ) and second Electrical Motor (EM 2 ) in dependence of the State Of Charge (SOC) level in the first Energy Storage System (ESS 1 ) and the availability of electrical energy for the second Electrical Motor (EM 2 ),

wherein
the Electronic Control Unit (ECU) is programmed to include an energy transfer mode in which the use of the second Electrical Motor (EM 2 ) for propulsive force is increased and the use of the first Electrical Motor (EM 1 ) for regenerative braking is increased such that the overall energy consumption is allowed to be increased as a result of friction losses from using more propulsion and braking force than desired for the resulting propulsive force, the energy transfer mode being selected manually or automatically when it is indicated that the State Of Charge (SOC) level in the first electrical Energy Storage System (ESS 1 ) is below a defined level and it is estimated that there is more electrical energy available for the second Electrical Connections (EC 2 ) connected to the second Electrical Motor (EM 2 ) than for the first Electrical Connections (EC 1 ) connected to the first Electrical Motor (EM 1 ).

2. A vehicle according to claim 1 , wherein the second Electrical Motor (EM 2 ) is electrically connected to and powered by a second Energy Storage System (ESS 2 ) and the Electronic Control Unit (ECU) is programmed such that it is estimated that there is more electrical energy available for propulsion of the second Electrical Motor (EM 2 ) when the second Energy Storage System (ESS 2 ) is able to provide an electrical power for propulsive force for a longer time than the first Energy Storage System (ESS 1 ) based on estimation of present or future vehicle operation conditions and/or when the second Energy Storage System (ESS 2 ) is able to provide energy with less reduction of the overall State Of Charge of the on board Energy Storage Systems (ESS 1 , ESS 2 ) compared with using the first electrical Energy Storage System (ESS 1 ) for providing electrical energy to the first Electrical Motor (EM 1 ).

3. A vehicle according to claim 1 , wherein the Electronic Control Unit (ECU) is programmed such that it is estimated that there is more available electrical energy for propulsion of the second Electrical Motor (EM 2 ) when the second Electrical Motor (EM 2 ) and/or a second Energy Storage System (ESS 2 ), electrically connected to the second Electrical Motor (EM 2 ), is receiving electrical power by the use of power collectors adapted to be connected to an external power supply during travel for supply of electric power to the second Electrical Motor (EM 2 ) and/or the second Energy Storage System (ESS 2 ).

4. A vehicle according to claim 3 , wherein the power collectors are electrically connected with the second electrical Energy Storage System (ESS 2 ) in order to recharge the second electrical Energy Storage System (ESS 2 ) during travel.

5. A vehicle according to claim 1 , wherein the first electrical Energy Storage System (ESS 1 ) is electrically isolated from the electrical energy sources electrically connected to the second Electrical Motor (EM 2 ) such that there is no possibility to directly transfer electric energy to or from the first electrical Energy Storage System (ESS 1 ) and the electrical energy sources electrically connected to the second Electrical Motor (EM 2 ).

6. A vehicle according to claim 1 , wherein the first Electrical Motor (EM 1 ) lacks the possibility to be supplied by electricity from an external power supply during travel, either directly or via charging of the first electrical Energy Storage System (ESS 1 ) during travel, while the second Electrical Motor (EM 2 ) is connected via the second Electrical Connections (EC 2 ) to power collectors, either directly or via charging of a second electrical Energy Storage System (ESS 2 ), adapted to be connected to an external power supply during travel.

7. A vehicle according to claim 1 , wherein the Electronic Control Unit (ECU) is programmed to use the second Electrical Motor (EM 2 ) for propulsion of the vehicle simultaneously as the first Electrical Motor (EM 1 ) is used for regenerative braking of the vehicle in order to charge the first electrical Energy Storage System (ESS 1 ) when the vehicle is controlled in the energy transfer mode.

8. A vehicle according to claim 1 , wherein the first Electrical Motor (EM 1 ) is drivingly connected to at least a first driven wheel different from at least a second driven wheel being drivingly connected to the second Electrical Motor (EM 2 ).

9. A vehicle according to claim 8 , wherein the vehicle is an articulated vehicle and the first Electrical Motor (EM 1 ) is drivingly connected to a driven wheel on a first part of an articulated vehicle and second Electrical Motor (EM 2 ) is drivingly connected to at least one driven wheel on a second part of an articulated vehicle, the first and second parts of the articulated vehicle being on different sides of an articulation of the vehicle.

10. A vehicle according to claim 8 , wherein the first Electrical Motor (EM 1 ) is drivingly connected to power a first driven axle connected to the first driven wheel and the second Electrical Motor (EM 2 ) is drivingly connected to power a second driven axle connected to the second driven wheel.

11. A vehicle according to claim 1 , wherein the first and second Electric Motors (EM 1 , EM 2 ) are drivingly connected to a common driven wheel, e.g. by powering a common third driven axle being connected to the driven wheel.

12. A method for controlling an electric propulsion system for a vehicle, the propulsion system comprising:
a first Electrical Motor (EM 1 ) for propulsion of the vehicle provided with first Electrical Connections (EC 1 ) designed to be connected to and powered by one or several electrical energy sources;
at least one driven wheel being drivingly connected to the first Electrical Motor (EM 1 );
a second Electrical Motor (EM 2 ) for propulsion of the vehicle provided with second Electrical Connections (EC 2 ) designed to be connected to and powered by one or several electrical energy sources;
at least one driven wheel being drivingly connected to the second Electrical Motor (EM 2 );
an on-board Energy Storage System (ESS 1 ) electrically connected to the first Electrical Motor (EM 1 ) via the first Electrical Connections (EC 1 ) in order to provide electrical power to power the first Electrical Motor (EM 1 ); and
an Electronic Control Unit (ECU) for control of the electric propulsion system, which method comprises the features of:
controlling the use of the first Electrical Motor (EM 1 ) and second Electrical Motor (EM 2 ) in

Assignees

• Volvo Truck Corp

Inventors

• Storm Jonas

Classifications

• B60K6/52 Primary

  Driving a plurality of drive axles, e.g. four-wheel drive · CPC title

• B60W2510/244

  Charge state · CPC title

• B60W10/26

  for electrical energy, e.g. batteries or capacitors · CPC title

• B60L2220/42

  with use of more than one motor · CPC title

• B60W2710/244

  Charge state · CPC title