Method of controlling an energy storage unit in a vehicle micro-hybrid system

• US 8,862,295 B2
• Filed: 01/05/2010
• Issued: 10/14/2014
• Est. Priority Date: 01/12/2009
• Status: Active Grant

• Current Assignee: Valeo Equipements Electriques Moteur (Valeo SE)
• Original Assignee: Valeo Equipements Electriques Moteur (Valeo SE)
• Inventors: Dessirier, Bruno, Ranier, Marc, Newiadomy, Serge, Soucaze-Guillous, Benoit, Masson, Philippe, Sardat, Pierre, Chemin, Michal, Matt, Jean-Claude
• Primary Examiner(s): HOLLOWAY, JASON R
• Application Number:
  US13/143,891
• Publication Number:
  US 20120062186A1
• Time in Patent Office: 1,743 Days
• Field of Search: 701/22, 701/36, 701/99, 701/29.1, 340/636.1, 340/636.11, 340/636.12, 340/636.15, 340/636.16, 340/636.18, 340/636.19, 180/65.29, 320/152, 320/153, 320/167
• US Class Current: 701/22
• CPC Class Codes: B60K 6/28 characterised by the electric energy storing means, e.g. batteries or capacitors
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2510/246 Temperature
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A method of controlling a supercapacitor energy storage unit (12), included in a motor vehicle micro-hybrid system, is disclosed. The storage unit is suitable for performing the functions of an alternator, starter and automatic stop-restart of the vehicle heat engine, regenerative braking and torque assistance. The energy storage unit (12) is a plurality of supercapacitor elementary cells connected in series (C1 to C10) and capable of delivering information (Vmax, Temp and DeltaV) on its internal status. The method includes various stages of: comparing a maximum elementary voltage (Vmax) with a first voltage threshold (Vmax1); comparing a temperature (Temp) with at least one temperature threshold (ST1=55° C., ST2=65° C. and ST3=70° C.); and, deciding on limitations of the availability of functions of the unit when the (Vmax) information reaches threshold (Vmax1) for a predetermined duration (T) and/or when the (Temp) information reaches the temperature threshold (ST1=55° C., ST2=65° C. and ST3=70° C.).

Claims

1. A method of controlling a supercapacitor energy storage unit (12) in a motor vehicle having a heat engine and a micro-hybrid system comprising an electrical rotating machine configured to operate in an alternator mode, a starter mode allowing an automatic stop-restart function of the vehicle heat engine, a regenerative braking mode and a torque assistance mode, said energy storage unit (12) comprising a plurality of supercapacitor elementary cells connected in series and delivering information on an internal status thereof, said energy storage unit (12) electrically connected to said electrical rotating machine and including a most charged elementary cell and a least charged elementary cell, said information delivered by said energy storage unit (12) including a maximum elementary voltage (Vmax) from said most charged elementary cell and a temperature (Temp) of said energy storage unit (12), the method comprises the steps of:

obtaining said maximum elementary voltage (Vmax) of said most charged elementary cell of said energy storage unit (12);

comparing said maximum elementary voltage (Vmax) with a first voltage threshold (Vmax1);

obtaining said temperature (Temp) of said energy storage unit (12);

comparing said temperature (Temp) with at least one temperature threshold; and

prohibiting at least one of said modes of operation of said electrical rotating machine at least when said maximum elementary voltage (Vmax) information reaches said first voltage threshold (Vmax1) for a predetermined duration (T) or when said temperature (Temp) reaches said at least one temperature threshold.

2. The method according to claim 1, further comprising the step of authorizing said at least one of said modes of operation when said maximum elementary voltage (Vmax) falls and reaches a second voltage threshold (Vmax2) lower than said first voltage threshold (Vmax1).

3. The method according to claim 1, wherein the step of prohibiting said at least one of said modes of operation comprises the step of prohibiting at least one of said regenerative braking mode and said torque assistance mode when said temperature (Temp) reaches a first temperature threshold (ST1).

8. The method according to claim 2, wherein said information delivered by said energy storage unit (12) includes health status information based on a difference in voltage (DeltaV) between said most charged elementary cell and said least charged elementary cell of said energy storage unit (12), said method further comprises the steps of:

comparing said health status (DeltaV) information with a third voltage threshold; and

when said health status (DeltaV) information reaches said third voltage threshold, informing a user of said motor vehicle of the need to at least one of replacing said energy storage unit (12) and increasing at least one of said first voltage threshold (Vmax1), said second voltage threshold (Vmax2) and said predetermined duration (T).

4. A method of controlling a supercapacitor energy storage unit (12) in a motor vehicle having a heat engine and a micro-hybrid system comprising an electrical rotating machine configured to operate in an alternator mode, a starter mode allowing an automatic stop-restart function of the vehicle heat engine, a regenerative braking mode and a torque assistance mode, said energy storage unit (12) comprising a plurality of supercapacitor elementary cells connected in series and delivering information on an internal status thereof, said energy storage unit (12) electrically connected to said electrical rotating machine and including a most charged elementary cell and a least charged elementary cell, said information delivered by said energy storage unit (12) including a maximum elementary voltage (Vmax) from said most charged elementary cell and a temperature (Temp) of said energy storage unit (12), the method comprises the steps of:

obtaining said maximum elementary voltage (Vmax) of said most charged elementary cell of said energy storage unit (12);

comparing said maximum elementary voltage (Vmax) with a first voltage threshold (Vmax1);

obtaining said temperature (Temp) of said energy storage unit (12);

comparing said temperature (Temp) with at least one temperature threshold; and

prohibiting at least one of said modes of operation of said electrical rotating machine at least when said maximum elementary voltage (Vmax) reaches said first voltage threshold (Vmax1) for a predetermined duration (T) or when said temperature (Temp) reaches said at least one temperature threshold;

the step of prohibiting said at least one of said modes of operation also comprises the step of prohibiting said starter mode and said heat engine automatic stop-restart function when said temperature (Temp) reaches a second temperature threshold (ST2) higher than said first temperature threshold (ST1).

5. The method according to claim 4, wherein the step of prohibiting said at least one of said modes of operation also comprises the step of regulating a voltage supplied by said electrical rotating machine operating in said alternator mode at a predetermined fixed value.

6. The method according to claim 5, wherein the step of prohibiting said at least one of said modes of operation also comprises the step of giving a warning to a user of said motor vehicle about a possible prohibition of all of said modes of operation when said temperature (Temp) reaches a third temperature threshold (ST3) higher than said second temperature threshold (ST2).

7. The method according to claim 6, wherein said first temperature threshold (ST1) is about 55°

C.;

wherein said second temperature threshold (ST2) is about 65°

C.; and

wherein said third temperature threshold (ST3) is about 70°

C.

10. The method according to claim 4, wherein the step of prohibiting at least one of said modes of operation comprises the step of prohibiting all of said modes of operation when said temperature (Temp) reaches a third temperature threshold (ST3) higher than said second temperature threshold (ST2) and when said motor vehicle is at rest.

9. A motor vehicle micro-hybrid system in a motor vehicle having a heat engine, said micro-hybrid system comprising:

an electrical rotating machine configured to operate in an alternator mode, a starter mode allowing an automatic stop-restart function of the vehicle heat engine, a regenerative braking mode and a torque assistance mode;

an energy storage unit (12) electrically connected to said electrical rotating machine and providing functionality of said electrical rotating machine for operating in said alternator mode, starter mode and said automatic stop-restart function of said vehicle heat engine, regenerative braking mode and torque assistance mode, said energy storage unit (12) having a plurality of supercapacitor elementary cells connected in series and delivering information on an internal status thereof; and

a control module (141) operatively connected to said energy storage unit (12);

said energy storage unit (12) including a most charged elementary cell and a least charged elementary cell;

said information delivered by said energy storage unit (12) including a maximum elementary voltage (Vmax) from said most charged elementary cell and a temperature (Temp) of said energy storage unit (12);

said control module (141) provided for;

comparing said maximum elementary voltage (Vmax) with a first voltage threshold (Vmax1);

comparing said temperature (Temp) with at least one temperature threshold, and

prohibiting at least one of said modes of operation of said electrical rotating machine at least when said maximum elementary voltage (Vmax) reaches said first voltage threshold (Vmax1) for a predetermined duration (T) or when said temperature (Temp) reaches said at least one temperature threshold.