Parallel hybrid vehicle optimal storage system

• US 7,795,839 B2
• Filed: 03/22/2010
• Issued: 09/14/2010
• Est. Priority Date: 03/13/2006
• Status: Expired due to Fees

• Current Assignee: Bowling Green State University
• Original Assignee: Bowling Green State University
• Inventors: Bloomfield, Aaron
• Primary Examiner(s): Tso; Edward
• Assistant Examiner(s): Fantu; Yalkew
• Application Number:
  US12/728,414
• Publication Number:
  US 20100174433A1
• Time in Patent Office: 176 Days
• Field of Search: 320/106
• US Class Current: 320/104
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y10S 903/902 Prime movers comprising electrical and internal combustion motors
• CPC Class Codes: Y10S 903/906 Motor or generator

Abstract

The present invention is a method and apparatus by which power is controlled in a hybrid electric vehicle such that high levels of performance and efficiency are realized. The present invention includes a method and apparatus developed to optimize the use of energy in a hybrid vehicle application from the hybrid energy storage device. The method and apparatus of the present invention is particularly useful with energy storage devices there the energy state, such as the state of charge, is readily determined by an easily measured attribute. Ultracapacitors and hydraulic storage cylinders are examples of the types of energy storage devices to which the present invention may be applied.

Claims

1. A hybrid electric vehicle comprising:

a drive train;

an electric motor for driving said drive train;

a power unit electrically coupled to said electric motor;

an electric energy storage system electrically coupled to said electric motor, said electric energy storage system adapted to recapture energy from the braking of said vehicle so as to be capable of discharging and recapturing energy through a series of discharge and energy recapture events, and having a maximum charge level and an actual minimum charge level; and

wherein said power unit and said electric energy storage system provide electricity to said electric motor for powering said vehicle; and

an electric energy storage controller programmed to control said electric energy storage system by setting an artificial minimum charge level to an initial level above said actual minimum charge level, and, during a series of discharge and energy recapture events, to be able to adjust said artificial minimum charge level such that;

(a) in the case where a discharge and energy recapture event results in the recapture of insufficient energy to recharge said electric energy storage system to said maximum charge level, said artificial minimum charge level is raised; and

(b) in the case where a discharge and energy recapture event results in the recapture of sufficient energy to recharge said electric energy storage system to said maximum charge level, said artificial minimum charge level is lowered.

2. A hybrid electric vehicle according to claim 1 wherein said electric energy storage controller is further programmed to control said electric energy storage system by restricting the raising of said artificial minimum charge level beyond a predetermined level below said maximum charge level.

3. A hybrid electric vehicle according to claim 1 wherein said electric energy storage controller is further programmed to control said electric energy storage system by restricting the lowering of said artificial minimum charge level beyond a predetermined level above said actual minimum charge level.

4. A hybrid electric vehicle according to claim 1 wherein said energy storage system is a bank of ultracapacitors.

5. A hybrid electric vehicle according to claim 1 additionally comprising an internal combustion engine and a generator adapted to charge said energy storage system with electrical energy.

6. A hybrid electric vehicle comprising:

a drive train;

an electric motor for driving said drive train;

a power unit electrically coupled to said electric motor;

an electric energy storage system electrically coupled to said electric motor, said electric energy storage system adapted to recapture energy from the braking of said vehicle so as to be capable of discharging and recapturing energy through a series of discharge and energy recapture events, and having a maximum charge level and an actual minimum charge level having a working range therebetween and which working is defined at its lower end by an artificial minimum charge level; and

wherein said power unit and said electric energy storage system provide electricity to said electric motor for powering said vehicle; and

an electric energy storage controller programmed to control said electric energy storage system by setting an artificial minimum charge level to an initial level above said minimum charge level, and, during a series of discharge and energy recapture events, to be able to adjust said artificial minimum charge level such that the working range of said electric energy storage system is biased toward said maximum charge level over said series of discharge and energy recapture events.