Hybrid vehicle

Filing Information

• Patent Number: US6209672
• Application Number: US9264817
• Filing date: 03/09/1999
• Issue date: 04/03/2001
• Predicted expiration date: 03/09/2019

• U.S. Classifications: 180/652  · 607/11  · 180/654  ·
• International Classifications: --
• International Classifications: 180 652 · 180 653 · 180 654 · 180 656 · 180 658 · 180165 · 60716 · 60718 · 60706 · 60711 · 290 17 · 290 40 R · 290 40 C · 322 16 ·
• Related U.S. Application Data:
  CROSS-REFERENCE TO RELATED APPLICATION
  This application claims priority from Provisional Application Ser. No. 60/100,095, filed Sep. 14, 1998.

Patent Family

Abstract

A hybrid vehicle comprising an an internal combustion engine controllably coupled to road wheels of the vehicle by a clutch, a traction motor coupled to road wheels of said vehicle, a starting motor coupled to the engine, both motors being operable as generators, a battery bank for providing electrical energy to and accepting energy from said motors, and a microprocessor for controlling these components is operated in different modes, depending on its instantaneous torque requirements, the state of charge of the battery bank, and other operating parameters. The mode of operation is selected by the microprocessor in response to a control strategy.

Independent Claims | See all claims (33)

1. 1. A hybrid vehicle, comprising: a controller capable of accepting inputs indicative of vehicle operating parameters and providing control signals in response to a control program; a battery bank; an internal combustion engine; a first electric starting motor electrically coupled to said battery bank for (a) accepting electrical energy from said battery bank and (b) providing electrical energy to said battery bank, and said first motor being mechanically coupled to said internal combustion engine, the combination of said internal combustion engine and said first electric motor being mechanically coupled to a clutch controlled by said controller for controllable torque-transmitting connection between said combination and road wheels of said vehicle, said first motor being responsive to commands from said controller, such that said first electric motor can be controlled to (1) accept torque from said engine to charge said battery bank, (2) accept energy from said battery bank to apply torque to said engine for starting said engine, (3) accept energy from said battery bank to apply torque to said road wheels to propel said vehicle, and (4) accept torque from said road wheels to charge said battery bank; and a second electric traction motor, electrically coupled to said battery bank, such that said second electric motor can be controlled for (a) accepting electrical energy from said battery bank and (b) providing electrical energy to said battery bank, said second motor being directly coupled to road wheels of said vehicle, without a controllable clutch disposed therebetween, such that said second motor is permanently connected to said road wheels for torque transmission therebetween, and said second motor being responsive to commands from said controller in order to (1) accept energy from said battery bank to apply torque to said road wheels to propel said vehicle, and (2) accept torque from said road wheels to charge said battery bank.
2. 15. A method for controlling the operation of a hybrid vehicle operable in a plurality of differing modes, comprising the steps of: providing a hybrid vehicle comprising an internal combustion engine for providing torque up to a maximum torque output (MTO), said engine being controllably coupled to road wheels of said vehicle by a clutch, a traction motor being coupled to road wheels of said vehicle, a starting motor coupled to said engine, both said motors being operable as generators, a battery bank for providing electrical energy to and accepting energy from said motors, and a controller for controlling operation of said engine, clutch, and first and second motors, and controlling flow of electrical energy between said motors and said battery bank, and operating said controller to control selection of the operational mode of said vehicle between a low-speed mode I, a cruising mode IV, and an acceleration mode V, wherein torque to propel said vehicle is provided by said traction motor, said engine, and both, respectively, in response to monitoring the instantaneous torque requirements required for propulsion of the vehicle (RL).
3. 27. A method for controlling the operation of a hybrid vehicle operable in a plurality of differing modes, comprising the steps of: providing a hybrid vehicle comprising an internal combustion engine for providing torque up to a maximum torque output (MTO), said engine being controllably coupled to road wheels of said vehicle by a clutch, a traction motor being coupled to road wheels of said vehicle, a starting motor coupled to said engine, both said motors being operable as generators, a battery bank for providing electrical energy to and accepting energy from said motors, and a controller for controlling operation of said engine, clutch, and first and second motors, and controlling flow of electrical energy between said motors and said battery bank, and operating said controller to control selection of the operational mode of said vehicle between a low-speed mode I and a cruising mode IV, wherein torque to propel said vehicle is provided by said traction motor or said engine, respectively, in response to monitoring the instantaneous torque requirements required for propulsion of the vehicle (RL), and wherein further according to said method, when said controller determines that transition of the operating mode of said vehicle from mode I to mode IV is desirable, said controller controls said starting motor to spin said engine for starting at a minimum speed of at least 300 rpm, and said clutch is not engaged for supply of torque from said engine to said road wheels until said engine is running at a speed at which it efficiently produces torque.
4. 29. A hybrid vehicle operable in a plurality of differing modes, said vehicle comprising an internal combustion engine for providing torque up to a maximum torque output (MTO) and at least one traction motor being coupled to road wheels of said vehicle, said at least one motor being operable as a generator, a battery bank for providing electrical energy to and accepting energy from said motor, a controller for controlling operation of said engine, and said at least one motor, and controlling flow of electrical energy between said motor and said battery bank, and at least one controllable inverter/charger connected between said motor and said battery bank, said controllable inverter/charger comprising a plurality of pairs of elements controllably switched in response to commands from said controller for operating said motor to supply propulsive torque to said road wheels in response to energy from said battery bank, and for converting torque transmitted from said road wheels to said motor into energy for recharging said battery bank, wherein said battery bank is configured as two separate battery sub-banks, each having positive and negative poles, the positive pole of one of said sub-banks being connected to the negative pole of the other of said sub-banks at a vehicle chassis connection, and the opposite poles of said battery sub-banks being connected across said pairs of elements of said at least one inverter/charger.
5. 30. A hybrid vehicle operable in a plurality of differing modes, said vehicle comprising an internal combustion engine for providing torque up to a maximum torque output (MTO) and at least one traction motor being coupled to road wheels of said vehicle, said at least one motor being operable as a generator, a battery bank for providing electrical energy to and accepting energy from said motor, a controller for controlling operation of said engine and said at least one motor, and controlling flow of electrical energy between said motor and said battery bank, and at least one controllable inverter/charger connected between said motor and said battery bank, said controllable inverter/charger comprising a plurality of pairs of elements controllably switched in response to commands from said controller for operating said motor to supply propulsive torque to said road wheels in response to energy from said battery bank, and for converting torque transmitted from said road wheels to said motor into energy for recharging said battery bank, wherein said battery bank is configured as a number of batteries connected by normally-open switching devices, such that said batteries are electrically isolated from one another in the event power is cut off from said switching devices.
6. 31. A hybrid vehicle operable in a plurality of differing modes, said vehicle comprising an internal combustion engine for providing torque up to a maximum torque output (MTO) and at least one traction motor being coupled to road wheels of said vehicle, without a controllable clutch disposed therebetween, such that said at least one motor is permanently connected to said road wheels for torque transmission therebetween, said at least one motor being operable as a generator, a battery bank for providing electrical energy to and accepting energy from said motor, a controller for controlling operation of said engine and said at least one motor, and controlling flow of electrical energy between said motor and said battery bank, and at least one controllable inverter/charger connected between said motor and said battery bank, said controllable inverter/charger comprising a plurality of pairs of elements controllably switched in response to commands from said controller for operating said motor to supply propulsive torque to said road wheels in response to energy from said battery bank, and for converting torque transmitted from said road wheels to said motor into energy for recharging said battery bank, wherein said motor has at least four phases, and wherein said motor is operated by said inverter/charger in response to control signals provided by said controller so that said motor provides constant torque from zero rpm to a base speed, and provides constant power at speeds greater than said base speed and less than a maximum speed.
7. 32. A hybrid vehicle operable in a plurality of differing modes, said vehicle comprising an internal combustion engine for providing torque up to a maximum torque output (MTO) and at least one traction motor being coupled to road wheels of said vehicle, without a controllable clutch disposed therebetween, such that said at least one motor is permanently connected to said road wheels for torque transmission therebetween, said at least one motor being operable as a generator, a battery bank for providing electrical energy to and accepting energy from said motor, a controller for controlling operation of said engine and said at least one motor, and controlling flow of electrical energy between said motor and said battery bank, and at least one controllable inverter/charger connected between said motor and said battery bank, said controllable inverter/charger comprising a plurality of pairs of elements controllably switched in response to commands from said controller for operating said motor to supply propulsive torque to said road wheels in response to energy from said battery bank, and for converting torque transmitted from said road wheels to said motor into energy for recharging said battery bank, wherein said motor is operated by said inverter/charger in response to control signals provided by said controller so that said motor provides constant torque from zero rpm to a base speed, and provides constant power at speeds greater than said bass speed and less than a maximum speed, and wherein the ratio between said base speed and said maximum speed is between about 3 and about 6:1.