Control system for an electrically propelled traction vehicle

• US 5,373,219 A
• Filed: 03/11/1993
• Issued: 12/13/1994
• Est. Priority Date: 03/31/1992
• Status: Expired due to Term

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Nash, James W., Beach, Frederick G., Grabowski, Francis M., Duke, Amy D., Curtis, Paul H.
• Primary Examiner(s): Ro, Bentsu
• Application Number:
  US08/029,845
• Time in Patent Office: 642 Days
• Field of Search: 318/34, 318/139, 318/432, 318/433, 318/434, 388/903, 388/907.5, 180/65.2, 180/65.3, 180/65.4, 180/65.5, 290/7, 290/8, 290/9, 290/10, 290/11, 290/14, 290/17, 290/21, 290/22, 290/24, 290/40 R, 290/40 A, 290/40 C, 290/45, 290/51
• US Class Current: 318/139
• CPC Class Codes: B60K 6/46 Series type
• CPC Class Codes: B60K 6/52 Driving a plurality of drive axles, e.g. four-wheel drive
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 2240/445 Temperature
• CPC Class Codes: B60L 2270/44 Heat storages, e.g. for cabin heating
• CPC Class Codes: B60L 3/12 Recording operating variables ; Monitoring of operating variables
• CPC Class Codes: B60L 50/12 using AC generators and DC motors
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 2510/0676 Engine temperature
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• 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: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y10S 903/916 with plurality of drive axles

Abstract

A control system for an electrical propulsion system for a large wheeled vehicle adapted to haul a payload, the vehicle having an internal combustion engine and an electric generating means driven by the engine. The control system measures selected parameters and controls the engine and generating means to maximize output, and records historical operating data relating to the vehicle and its systems, and has a 2 digit display that provides information useful in troubleshooting problems.

Claims

1. A control system for an electrical propulsion system for a wheeled vehicle adapted to haul a payload, the vehicle being equipped with a plurality of adjustable speed electric traction motors mechanically coupled in driving relation to separate wheels on the vehicle, the vehicle having an internal combustion engine and an electric generating means operatively connected to the engine and to the traction motors and providing electric power at its output for energizing the traction motors, the electric generating means being of the type which can vary the voltage and current of the electric power provided at its output responsive to control signals being applied thereto and having a first predetermined operating temperature of a component thereof that correlates to a rating at which continuous operation can occur without substantial risk of damage thereto, and a maximum predetermined operating temperature higher than the first predetermined operating temperature of the component during which continuous operation would create a substantial risk of damage to the electric generating means, said control system comprising:

processing means including memory means for controlling the operation of the internal combustion engine and the electric generating means;

means for measuring the ambient temperature of the environment in which the vehicle is operating and generating a signal indicative of said measured ambient temperature and applying the same to said processing means;

means for measuring the output voltage of the electric generating means and generating a signal indicative of said measured output voltage and applying the same to said processing means;

means for measuring the output current of the electric generating means and generating a signal indicative of said measured output current and applying the same to said processing means;

said processing means being adapted to generate the control signals and apply the same to the electric generating means to increase the electric power provided at its output above the continuous rating and to generate and apply the control signals to the electric generating means to return the same to the continuous rating responsive to a calculated simulated temperature reaching the maximum predetermined operating temperature of the component of the electric generating means.

2. A system as defined in claim 1 wherein said simulated temperature is a function of the measured ambient temperature, the measured output voltage, the measured output current and predetermined physical characteristics of the electric generating means.

3. A system as defined in claim 2 wherein said electric generating means is an alternator adapted to convert the mechanical power of the engine to a three phase alternating current electrical output.

4. A system as defined in claim 3 wherein said component comprises a rotor of said alternator.

5. A system as defined in claim 4 wherein said predetermined physical characteristics comprise at least the heat storage capacity of said rotor of said alternator.

6. A system as defined in claim 4 wherein said predetermined physical characteristics comprise at least the resistance of said rotor of said alternator at a predetermined temperature.

7. A system as defined in claim 4 wherein said predetermined physical characteristics comprise at least the surface heat transfer coefficient of said rotor of said alternator.

8. A system as defined in claim 7 wherein said surface heat transfer coefficient varies in proportion to the speed at which the engine operates, said system having a plurality of coefficients stored in said memory means of said processing means corresponding to a plurality of preselected engine speeds.

9. A system as defined in claim 8 wherein three coefficients are stored in said memory means, said coefficients corresponding to a low idle speed, a high idle speed and a rated engine speed.

10. A system as defined in claim 1 wherein said processing means is adapted to generate said control signals on a periodic basis.

11. A system as defined in claim 10 wherein said processing means generates said control signals approximately every 5 seconds.

12. A system as defined in claim 1 wherein said electric generating means is adapted to vary the output voltage and output current to said traction motors to maintain a constant horsepower rating responsive to said control signals, said processing means being adapted to generate said control signals to said electric generating means to increase said output current and output voltage in proportion to maintain a constant horsepower rating when operating said electric generating means whereby the temperature of said component is above said first predetermined operating temperature.

13. A system as defined in claim 2 wherein said processing means calculates said simulated temperature by executing the equation:

##EQU2## where T=temperature rise of rotor (°

C.),

Δ

t=Time step,

H=Surface heat transfer coefficient (Watts/C),

C=Heat storage capacity (watt-sec./°

C.),

R=Resistance of rotor (ohms),

I=RMS amps during Δ

t, and

T_amb =Ambient temperature (°

C).

14. An electrical propulsion system for a wheeled vehicle adapted to haul a payload, the vehicle having an internal combustion engine for powering the vehicle, said system comprising:

a plurality of adjustable speed electric traction motors mechanically coupled in driving relation to separate wheels on the vehicle,

an electric alternator operatively connected to the engine and to said traction motors and providing electric power at its output for energizing said traction motors, said electric alternator being of the type which has a rotor and an output and which can be controlled to vary the voltage and current of the electric power provided at its output responsive to control signals being applied thereto and having a first predetermined operating temperature of said rotor thereof that correlates to a rating at which continuous operation can occur without substantial risk of damage thereto, and a maximum predetermined operating temperature higher than said first predetermined operating temperature of said rotor during which continuous operation would create a substantial risk of damage to said electric alternator,

processing means including memory means for controlling the operation of the internal combustion engine and said electric alternator;

means for measuring the ambient temperature of the environment in which the vehicle is operating and generating a signal indicative of said measured ambient temperature and applying the same to said processing means;

means for measuring the output voltage of the electric alternator and generating a signal indicative of said measured output voltage and applying the same to said processing means;

means for measuring the output current of said electric alternator and generating a signal indicative of said measured output current and applying the same to said processing means;

said processing means being adapted to generate the control signals and apply the same to said electric alternator to increase the electric power provided at its output above the continuous rating and to generate and apply the control signals to said electric alternator to return the same to said continuous rating responsive to a calculated simulated temperature reaching the maximum predetermined operating temperature of said rotor of said electric alternator, said simulated temperature being a function of the measured ambient temperature, the measured output voltage, the measured output current and predetermined physical characteristics of said electric alternator.

15. A control system for an electrical propulsion system for a wheeled vehicle adapted to haul a payload, the vehicle being equipped with a plurality of adjustable speed electric traction motors mechanically coupled in driving relation to separate wheels on the vehicle, the vehicle having an internal combustion engine and an electric generating means operatively connected to the engine and to the traction motors and providing electric power at its output for energizing the traction motors, the electric generating means being of the type which can vary the voltage and current of the electric power provided at its output responsive to control signals being applied thereto, the engine having a predetermined nominal horsepower rating, said control system comprising:

processing means including memory means for controlling the operation of the internal combustion engine and the electric generating means;

means for measuring the operating speed of the engine and generating a signal indicative of said measured speed and applying the same to said processing means;

said processing means being adapted to generate the control signals and apply the same to the electric generating means to vary the electric power provided at its output and therefore vary the load being applied on the engine, said processing means being adapted to operate in one of at least two horsepower loading modes, one of said modes being a manual mode whereby the electric power provided at the output of said electric generating means is set to a predetermined value corresponding to the nominal horsepower rating of the engine, the other of said modes being an automatic mode whereby the electric power provided at the output of said electric generating means is set at a predetermined nominal value, said processing means being adapted to generate the control signals and apply the same to the electric generating means to increase the electric power provided at the output thereof above said predetermined nominal value up to a maximum variable level that is determined by said processing means receiving a signal from said measuring means indicative of said measured speed dropping below a predetermined speed.

16. A system as defined in claim 15 further comprising means for selecting one of said horsepower loading modes.

17. A system as defined in claim 15 wherein the electric generating means comprises an electrical alternator and the internal combustion engine comprises a diesel engine.

18. A control system for an electrical propulsion system for a wheeled vehicle adapted to haul a payload, the vehicle being equipped with a plurality of adjustable speed electric traction motors mechanically coupled in driving relation to separate wheels on the vehicle, the vehicle having an internal combustion engine with a nominal horsepower rating and an electric generating means operatively connected to the engine and to the traction motors and providing electric power at its output for energizing the traction motors, the electric generating means being of the type which can vary the voltage and current of the electric power provided at its output responsive to control signals being applied thereto, the electric generating means having a nominal output power level that loads the engine at its nominal horsepower rating, said control system comprising:

processing means including memory means for controlling the operation of the internal combustion engine and the electric generating means;

means for measuring the operating speed of the engine and generating a signal indicative of said measured speed and applying the same to said processing means;

said processing means being adapted to generate the control signals and apply the same to the electric generating means to vary the electric power provided at its output and therefore vary the load being applied on the engine, said processing means being adapted to generate the control signals and apply the same to the electric generating means to increase the electric power provided at the output thereof above said nominal output power level up to a maximum variable level that is determined by said processing means receiving the signal from said measuring means indicative of said measured operating speed of the engine dropping below a predetermined speed.

19. A system as defined in claim 18 wherein said processing means is adapted to selectively operate in one of at least first and second loading modes, said first mode being a manual mode whereby the electric power provided at the output of said electric generating means is set to said nominal output power level, said second mode being an automatic mode whereby the electric power provided at the output of said electric generating means is set at said nominal output power level, said processing means being adapted to generate the control signals and apply the same to the electric generating means to increase the electric power provided at the output thereof above said nominal output power level up to a maximum variable level that is determined by said processing means receiving the signal from said measuring means indicative of said measured operating speed of the engine dropping below said predetermined speed.

20. A method of operating an electrical propulsion system of a wheeled vehicle adapted to haul a payload, the vehicle being equipped with a plurality of adjustable speed electric traction motors mechanically coupled in driving relation to separate wheels on the vehicle, the vehicle having an internal combustion engine with a nominal horsepower rating, and an electric generating means operatively connected to the engine and to the traction motors and providing electric power at its output for energizing the traction motors, the electric generating means being of the type which can vary the voltage and current of the electric power provided at its output responsive to control signals being applied thereto, the system having processing means for controlling the operation of the internal combustion engine and the electric generating means, said processing means being adapted to generate the control signals and apply the same to the electric generating means to vary the electric power provided at its output and therefore vary the load being applied on the engine, and means for measuring the operating speed of the engine and generating a signal indicative of said measured speed and applying the same to said processing means, said method comprising the steps of:

generating the control signals and applying the same to the electric generating means to increase the load being applied on the engine;

generating the control signals and applying the same to the electric generating means to maintain the load being applied on the engine when the measured operating speed of the engine falls below a predetermined value.

21. A method of operating an electrical propulsion system for a wheeled vehicle which is adapted to haul a payload, the vehicle being equipped with a plurality of adjustable speed electric traction motors mechanically coupled in driving relation to separate wheels on the vehicle, the vehicle having a diesel engine with a nominal horsepower rating, and an electric alternator operatively connected to the engine and to the traction motors and providing electric power at its output for energizing the traction motors, the electric alternator being of the type which can vary the voltage and current of the electric power provided at its output responsive to control signals being applied thereto, the system having processing means for controlling the operation of the diesel engine and the electric alternator, said processing means being adapted to generate the control signals and apply the same to the electric alternator to vary the electric power provided at its output and therefore vary the load being applied on the engine, and means for measuring the operating speed of the engine and generating a signal indicative of said measured speed and applying the same to said processing means, said method comprising the steps of:

generating the control signals and applying the same to the electric alternator to operate the alternator at a predetermined alternator output that causes the engine to operate near its nominal horsepower rating;

measuring the operating speed of the engine and generating the control signals and applying the same to the electric alternator to increase the load being applied to the engine until the measured operating speed of the engine falls below a predetermined value; and

,

generating the control signals and applying the same to the electric alternator to operate the alternator at an alternator output level that causes the engine to operate at least at said predetermined value of operating speed.

22. A control system for an electrical propulsion system for a wheeled vehicle adapted to haul a payload, the vehicle being equipped with a plurality of adjustable speed electric traction motors mechanically coupled in driving relation to separate wheels on the vehicle, the vehicle having an internal combustion engine and an electric generating means operatively connected to the engine and to the traction motors and providing electric power at its output for energizing the traction motors, the electric generating means being of the type which can vary the voltage and current of the electric power provided at its output responsive to control signals being applied thereto and having a first predetermined operating temperature of a component thereof that correlates to a rating at which continuous operation can occur without substantial risk of damage thereto, and a maximum predetermined operating temperature higher than the first predetermined operating temperature of the component during which continuous operation would create a substantial risk of damage to the electric generating means, said control system comprising:

processing means including memory means for controlling the operation of the internal combustion engine and the electric generating means, said processing means including time and calendar means for providing time and date stamps for selective signals that are received by said processing means;

means for measuring preselected electrical parameters of the electric generating means and generating electrical signals respectively indicative of said measured electrical parameters and applying the same to said processing means;

means for measuring preselected mechanical and operating parameters of the engine and generating electrical signals respectively indicative of said measured mechanical and operating parameters and applying the same to said processing means;

means for measuring preselected mechanical and operating parameters of the vehicle and generating electrical signals respectively indicative of said measured mechanical and operating parameters and applying the same to said processing means;

said processing means being adapted to receive said electrical signals from each of said measuring means and write selective historical data in said memory means relating to the history of operation of the vehicle, the electric generating means and the engine.

23. A system as defined in claim 22 wherein said processing means writes said historical data in said memory means and maintains said data for predetermined periods of time.

24. A system as defined in claim 23 wherein said historical data provides a daily record of selective mechanical, electrical and operating parameters.

25. A system as defined in claim 23 wherein said historical data provides a record of selective mechanical, electrical and operating parameters for a predetermined number of quarters of a year.

26. A system as defined in claim 23 wherein said historical data includes data indicating the time duration of selected operating parameters of the vehicle.

27. A system as defined in claim 23 wherein said historical data includes data comprising the cumulative total of selected operating parameters.

28. A system as defined in claim 26 wherein said historical data includes data that indicates the time duration of operation of the engine, operation of the vehicle, operation of the electric generating means, and operation of the vehicle above a predetermined speed.

29. A system as defined in claim 22 including display means operatively connected to said processing means, said display means having a multiple digit readout, said processing means being adapted to generate electrical signals to said display means for providing selected visual indications of a plurality of operational parameters relating to the vehicle and said system.

30. A system as defined in claim 29 wherein said display means is adapted to display a plurality of two digit codes, each of which indicates a status condition relating to the operation of the vehicle and the system.

31. A system as defined in claim 30 wherein a description of troubleshooting techniques is associated with each of said plurality of two digit codes.

32. A system as defined in claim 31 wherein said description of troubleshooting techniques is accessed via an operator input means associated with said display means.

33. A control system for an electrical propulsion system for a wheeled vehicle adapted to haul a payload, the vehicle being equipped with a plurality of adjustable speed electric traction motors mechanically coupled in driving relation to separate wheels on the vehicle, the vehicle having an internal combustion engine and an electric generating means operatively connected to the engine and to the traction motors and providing electric power at its output for energizing the traction motors, said control system comprising:

processing means including memory means for controlling the operation of the internal combustion engine and the electric generating means, said processing means including time and calendar means for providing time and date stamps for selective signals that are received by said processing means, and to determine preselected fault conditions in response to receiving signals indicative of preselected mechanical and electrical parameters that are outside of predetermined limits;

means for measuring preselected electrical parameters of the electric generating means and generating electrical signals respectively indicative of said measured electrical parameters and applying the same to said processing means;

means for measuring preselected mechanical and operating parameters of the engine and generating electrical signals respectively indicative of said measured mechanical and operating parameters and applying the same to said processing means;

means for measuring preselected mechanical and operating parameters of the vehicle and generating electrical signals respectively indicative of said measured mechanical and operating parameters and applying the same to said processing means;

override switch means operatively connected to said processing means, and adapted to override a fault condition responsive to actuation thereof in the absence of an inhibiting condition being established by said processing means;

said processing means being adapted to receive said electrical signals from each of said measuring means and determine a fault condition and write data indicative of said fault condition in said memory means, said processing means stopping the vehicle in response to the fault condition being determined.

34. A system as defined in claim 33 further including display means operatively connected to said processing means, said display means having a multiple digital readout, said processing means being adapted to generate electrical signals to said display means for providing selected visual indications of a plurality of operational parameters relating to the vehicle and said system, including preselected fault conditions.

35. A system as defined in claim 34 wherein said display means comprises at least one logic screen for providing troubleshooting aid.

36. A system as defined in claim 35 wherein said at least one logic screen for providing troubleshooting aid comprises two logic screens.

37. A system as defined in claim 35 wherein said at least one logic screen contains ladder diagrams to allow a determination of which signal is preventing the control system from achieving an acceleration or a retard state.

38. A system as defined in claim 37 wherein said ladder diagrams comprise operator inputs and propulsion system feedbacks.

39. A system as defined in claim 33 wherein said processing means selectively includes a predetermined override limit for preselected fault conditions, said processing means generating said inhibiting condition in response to said limit being reached.

40. A system as defined in claim 34 wherein said display means includes a reset means which when actuated, clears said visual indications therefrom, said electrical signals of said operational parameters and said preselected fault conditions being written in said memory means of said processing means.

41. A system as defined in claim 33 wherein said processing means includes means for establishing a predetermined rate at which said processing means writes into said memory means the electrical signals generated from each of said measuring means, said predetermined rate being adjustable.

42. A system as defined in claim 33 further including a snapshot switching means operatively connected to said processing means, said snapshot switching means being adapted to write into said memory means the electrical signals generated from each of said measuring means in response to actuation of said snapshot switching means.