Roadway-powered electric vehicle system

• US 5,669,470 A
• Filed: 05/05/1994
• Issued: 09/23/1997
• Est. Priority Date: 05/05/1994
• Status: Expired due to Term

• Current Assignee: HR Ross Industries Incorporated
• Original Assignee: HR Ross Industries Incorporated
• Inventors: Ross, Howard R.
• Primary Examiner(s): Merritt, Karen B.
• Assistant Examiner(s): LOWE, SCOTT
• Application Number:
  US08/238,990
• Time in Patent Office: 1,237 Days
• Field of Search: 191/2, 191/3, 191/4, 191/5, 191/6, 191/7, 191/10, 180/165, 180/2.1, 320/2, 307/9.1, 307/10.1, 246/187 R, 246/187 A, 246/187 B, 246/187 C
• US Class Current: 191/10
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 2210/20 AC to AC converters
• CPC Class Codes: B60L 5/005 without mechanical contact between the collector and the power supply line
• CPC Class Codes: B60L 50/30 using propulsion power stored mechanically, e.g. in fly-wheels
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 53/126 Methods for pairing a vehicle and a charging station, e.g. establishing a one-to-one relation between a wireless power transmitter and a wireless power receiver
• CPC Class Codes: B60L 53/36 by positioning the vehicle
• CPC Class Codes: B60L 7/14 for vehicles propelled by ac motors
• 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: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A roadway-powered electric vehicle system includes: (1) an all-electric vehicle; and (2) a roadway network over which the vehicle travels. The all-electric vehicle has one or more onboard energy storage elements or devices that can be rapidly charged or energized with energy obtained from an electrical current, such as a network of electromechanical batteries. The electric vehicle further includes an on-board controller that extracts energy from the energy storage elements, as needed, and converts such extracted energy to electrical energy used to propel the electric vehicle. The energy storage elements may be charged while the vehicle is in operation. The charging occurs through a network of power coupling elements, e.g., coils, embedded in the roadway. As the vehicle passes over such power coupling elements as it is driven on the roadway network, electrical current is inductively coupled to corresponding onboard power coupling elements, e.g., coils, and used to charge the onboard energy storage devices. The roadway network need only be energized with the power coupling elements at strategic locations. The roadway network may comprise existing roadways and highways that have been modified to include the embedded power coupling elements, e.g., coils.

Claims

1. A roadway-powered electric vehicle (EV) comprising:

a vehicle frame supported by front and rear suspension systems, including front and rear wheels;

an onboard power receiving module mounted on an underneath side of said vehicle frame that receives electrical power coupled thereto from a roadway power transmitting module embedded in a roadway over which the EV travels, wherein a first ac electrical current passing through the roadway power transmitting module has a frequency of from between 1 and 10 khz;

an onboard energy storage means for storing and delivering electrical energy;

an electric drive means coupled to at least one of said front or rear suspension systems for driving a least one of said front and rear wheels; and

an onboard power controller means for receiving electrical power from said onboard power receiving module and directing it to said onboard energy storage means, and for selectively delivering electrical energy from said energy storage means to said electric drive means in order to provide operating power for said EV.

2. The roadway-powered EV as set forth in claim 1 wherein said first ac electrical current has a frequency of between 2.5 and 3.5 KHz.

3. The roadway-powered EV as set forth in claim 1 wherein said onboard energy storage means comprises an electromechanical battery (EMB) system, said electromechanical battery system being characterized by a plurality of EMB modules connected in a parallel network, each EMB module having a specific energy of at least a kW-h, each EMB module having:

a sealed housing, a rotor within the sealed housing mounted on magnetic bearings, an array of magnets mounted on the rotor in a specific array so as to set up a prescribed rotor magnetic field pattern, and a set of stationary coils positioned to interact with said prescribed rotor magnetic field pattern;

an alternating current applied to said set of stationary coils setting up a rotating magnetic field that interacts with the prescribed rotor magnetic field pattern so as to cause said rotor to spin, the spinning of said rotor representing the storage of energy; and

the spinning of the rotor causing the prescribed rotor magnetic field pattern to interact with said set of stationary coils so as to induce an ac voltage thereon, said ac voltage representing the extraction of energy from said EMB;

whereby said EMB functions as a motor/generator depending upon whether electrical energy is being applied thereto or extracted therefrom.

4. The roadway-powered EV as set forth in claim 1 wherein said roadway power transmitting module comprises a first electrical coil embedded in the roadway, and wherein said onboard power receiving module comprises a second electrical coil, and wherein the first ac electrical current passes through said first coil and sets up an alternating magnetic field that induces a second ac electrical current in the second electrical coil, said first electrical coil and said second electrical coil thereby becoming inductively coupled to each other whenever the second electrical coil passes over the first electrical coil.

5. The roadway-powered EV as set forth in claim 4 wherein said onboard power controller means includes:

microprocessor controller means for generating a set of control signals that control said EV; and

a power director circuit connected to said onboard energy storage means and controlled by said microprocessor controller means, said power director circuit comprising;

ac-to-ac converter means electrically connected to the second coil for converting the second ac current inductively coupled in the second coil to a third ac current having a variable frequency set by a frequency control signal included within said set of control signals generated by said microprocessor controller means;

bi-directional matrix converter means for converting an ac voltage generated by said onboard energy storage means to an appropriate electrical drive signal as controlled by a pulse width control signal included within said set of control signals generated by said microprocessor controller means, said electrical drive signal being coupled to the electric drive means of said EV;

a switch matrix that selectively connects each of a plurality of energy storage modules included within a parallel network of energy storage modules to either said ac-to-ac converter means or to said bi-directional matrix converter means as a function of said control signals generated by said microprocessor controller means;

said microprocessor controller means thereby controlling whether electrical energy is directed to, and hence stored within, the parallel network of energy storage modules, or whether electrical energy is withdrawn from the parallel network of energy storage modules and directed to the electric drive means.

6. The roadway-powered EV as set forth in claim 5 wherein each of said energy storage modules is an electromechanical battery, said roadway-powered EV further including sensor means coupled to said microprocessor controller means for sensing a rotational speed of a rotor of each energy storage modules module within said parallel network of energy storage modules, said rotational speed providing a measure of the energy stored within each energy storage module, said measure of the energy stored within each energy storage module being used by said microprocessor controller means to control said switch matrix in an appropriate manner so that at least one of said energy storage modules can receive energy from said ac-to-ac conversion means at the same time that another of said energy storage modules is providing a source of energy for driving said electric drive means, whereby said EV may operate at the same time that it is being recharged with electrical energy.

7. The roadway-powered EV as set forth in claim 5 wherein said electric drive means includes means for generating a regenerative electrical current whenever said EV is coasting or braking, and wherein said bi-directional matrix converter means converts said regenerative electrical current to a fourth electrical current that may be applied to at least one of the energy storage modules of said parallel network of energy storage modules through said switch matrix, whereby energy associated with said regenerative electrical current is stored within said parallel network of energy storage modules.

8. The roadway-powered EV as set forth in claim 4 wherein said second coil is mounted on a movable assembly attached to an underneath side of said EV, and wherein said onboard power controller means includes positioning means for selectively positioning said movable assembly in order to optimize inductive coupling between said second coil and said first coil.

9. The roadway-powered EV as set forth in claim 8 wherein the positioning means for selectively positioning the movable assembly to optimize inductive coupling between said second coil and said first coil includes reducing means for selectively reducing an air gap between said first coil and said second coil whenever said EV is stopped, whereby vertical distance between said movable assembly and said roadway may be selectively reduced whenever said EV stops.

10. The roadway-powered EV as set forth in claim 8 wherein said positioning means for selectively positioning said movable assembly to optimize inductive coupling between said second coil and said first coil includes guiding means for automatically laterally guiding said EV so that said second coil is properly aligned with said first coil.

11. The roadway-powered EV as set forth in claim 8 wherein said positioning means for selectively positioning said movable assembly to optimize inductive coupling between said second coil and said first coil includes reducing means for selectively reducing an air gap between said first coil and said second coil whenever said EV is stopped, and guiding means for automatically laterally guiding said EV so that said second coil is properly laterally aligned with said first coil as the air gap is reduced.

12. A roadway-powered electric vehicle (RPEV) system comprising:

a network of highways and roadways that have been electrified with a multiplicity of roadway power transmitting modules embedded in the highways and roadways at select locations, each of said roadway power transmitting modules being connected to receive power from an electrical utility; and

at least one RPEV that traverses said network of highways and roadways using electrical power coupled to said at least one RPEV from the electrified highways and roadways as said RPEV travels over the locations of the highways and roadways that have been electrified, said RPEV including;

a vehicle frame supported by front and rear suspension systems, including front and rear wheels,

an onboard power receiving module mounted on an underneath side of the vehicle frame that receives electrical power coupled thereto from a roadway power transmitting module embedded in a roadway at the select locations that have been electrified, wherein a first ac electrical current passing through the roadway power transmitting module has a frequency of from between 1 and 10 khz,

an onboard energy storage means for storing and delivering electrical energy,

an electric drive means coupled to at least one of said front or rear suspension systems for driving at least one of said front and rear wheels, and

an onboard power controller means for receiving electrical power from said onboard power receiving module and directing it to said onboard energy storage means, and for selectively delivering electrical energy from said onboard energy storage means to said electric drive means in order to provide operating power for said EV.

13. The RPEV system as set forth in claim 12 wherein the select locations of said network of highways and roadways that have been electrified include no more than approximately 10% of the linear length of said roadways and highways.

14. The RPEV system as set forth in claim 12 wherein said onboard energy storage means comprises an electromechanical battery (EMB) system, said electromechanical battery system having at least one EMB, said EMB having a specific energy of at least 1 kW-h achieved by rotating a rotor sealed in an evacuated housing at rotational speeds in excess of 100,000 RPM as driven by an electrical input power signal applied thereto, an electrical output power signal being generated as a function of the speed of the rotating rotor;

said electrical output power signal representing the extraction of energy from said EMB;

whereby said EMB functions as a motor/generator depending upon whether electrical power is being applied thereto as said electrical power input signal or extracted therefrom as said electrical power output signal.

15. The RPEV system as set forth in claim 12 wherein the select locations of said network of highways and roadways that have been electrified include intersections where the RPEV is likely to be stopped for a time, and passenger loading/unloading zones where the RPEV will be stopped for a time.

16. The RPEV system as set forth in claim 15 wherein the network of highways and roadways includes parking/garaging locations, and further wherein said parking/garaging locations are electrified with said roadway power transmitting modules.

17. The RPEV system as set forth in claim 12 wherein each of said roadway power transmitting modules is electrically connected to the electrical utility via a power conditioner circuit, said power conditioner circuit comprising converting means for converting the electrical power obtained from the electrical utility to a form that can be efficiently and safely transmitted to the onboard power receiving module of the RPEV.

18. The RPEV system as set forth in claim 17 wherein said roadway power transmitting module comprises a first electrical coil embedded in the roadway, and wherein said onboard power receiving module comprises a second electrical coil, and wherein said electrical power conversion means of said power conditioner circuit converts electrical power obtained from the electrical utility to said first ac electrical current, and applies said first ac electrical current to said first coil to set up an alternating magnetic field, said alternating magnetic field inducing a second ac electrical current in the second electrical coil, said first electrical coil and said second electrical coil thereby being inductively coupled to each other whenever said second electrical coil passes over said first electrical coil.

19. The RPEV system as set forth in claim 18 wherein said power converter comprises an ac converter that includes means for converting 3-phase 50/60 Hz power obtained from the electrical utility to said first ac electrical current.

20. The RPEV system as set forth in claim 19 wherein said first ac electrical current has a frequency of between 2.5 and 3.5 KHz.

21. The RPEV system as set forth in claim 18 wherein said electromechanical battery system comprises a plurality of energy storage modules connected in a parallel network, and wherein said onboard power controller means includes:

microprocessor controller means for generating a set of control signals that control said EV; and

a power director circuit connected to said onboard energy storage means and controlled by said microprocessor controller means, said power director circuit comprising;

ac-to-ac converter means electrically connected to the second coil for converting the second ac current inductively coupled in the second coil to a third ac current having a variable frequency set by a frequency control signal included within said set of control signals generated by said microprocessor controller means;

bi-directional matrix converter means for converting an ac voltage generated by said onboard energy storage means to an appropriate electrical drive signal as controlled by a pulse width control signal included within said set of control signals generated by said microprocessor controller means, said electrical drive signal being coupled to the electric drive means of said EV;

a switch matrix that selectively connects each of said plurality of energy storage modules included within said parallel network of energy storage modules to either said ac-to-ac converter means or to said bi-directional matrix converter means as a function of said control signals generated by said microprocessor controller means;

said microprocessor controller means thereby controlling whether electrical power is directed to, and hence stored within, the parallel network of energy storage modules, or whether electrical power is withdrawn from the parallel network of energy storage modules and directed to the electric drive means.

22. The RPEV system as set forth in claim 21 wherein each of said energy storage modules is an electromechanical battery, said RPEV system further including sensor means coupled to said microprocessor controller means for sensing a rotational speed of a rotor of each energy storage module within said parallel network of energy storage modules, said rotational speed providing a measure of the energy stored within each energy storage module, said measure of the energy stored within each energy storage module being used by said microprocessor controller means to control said switch matrix in an appropriate manner so that at least one of said energy storage modules can receive energy from said ac-to-ac conversion means at the same time that another of said energy storage modules is providing a source of energy for driving said electric drive means, whereby each of said RPEV'"'"'s may operate at the same time that it is being recharged with electrical energy.

23. The RPEV system as set forth in claim 18 wherein said second coil is mounted on a movable assembly attached to an underneath side of said RPEV, and wherein said onboard power controller means includes positioning means for selectively positioning said movable assembly in order to optimize inductive coupling between said second coil and said first coil.

24. The RPEV system as set forth in claim 23 wherein the positioning means for selectively positioning the movable assembly to optimize inductive coupling between said second coil and said first coil includes reducing means for selectively reducing an air gap between said first coil and said second coil whenever said RPEV is stopped, whereby a vertical distance between said movable assembly and said roadway may be selectively reduced.

25. The RPEV system as set forth in claim 23 wherein said positioning means for selectively positioning said movable assembly to optimize inductive coupling between said second coil and said first coil includes guiding means for automatically laterally guiding said RPEV so that said second coil is properly aligned with said first coil.

26. The RPEV system as set forth in claim 23 wherein said positioning means for selectively positioning said movable assembly to optimize inductive coupling between said second coil and said first coil includes reducing means for selectively reducing an air gap between said first coil and said second coil whenever said RPEV is stopped, and guiding means for automatically laterally guiding said RPEV so that said second coil is properly laterally aligned with said first coil as the air gap is reduced.