High power, high frequency, liquid-cooled transmission cable and charging system

• US 5,670,860 A
• Filed: 06/06/1995
• Issued: 09/23/1997
• Est. Priority Date: 06/06/1995
• Status: Expired due to Term

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: Hughes Electronics Corporation (Rtx Corporation)
• Inventors: Asbury, Victor O., Rosas, Juventino, Conrady, Clint, Yeow, Eddie, Woody, George R., Ramos, Sergio
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): Law, Patrick B.
• Application Number:
  US08/467,423
• Time in Patent Office: 840 Days
• Field of Search: 320/2, 174/15.1, 174/17 LF, 174/15.4, 174/15.6, 174/11 R, 174/31 R, 174/29, 165/104.25, 505/885, 505/886
• US Class Current: 320/109
• CPC Class Codes: B60K 1/04 of the electric storage means for propulsion exchanging batteries for electric propulsion of vehicles B60L53/80; for auxiliary purposes only B60R16/04; supplying batteries to, or removing batteries from, vehicles B60S5/06
• CPC Class Codes: B60L 53/18 Cables specially adapted for charging electric vehicles
• CPC Class Codes: H01B 7/423 using a cooling fluid
• CPC Class Codes: H02J 7/0042 characterised by the mechanical construction
• 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 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A charging system employing a liquid-cooled transmission cable for transferring power. The transmission cable has a central tube with an extruded member disposed therewithin for carrying coolant. A plurality of layers of coaxial tubular wire braid are disposed around the central tube that carry charging current and that are separated by a layers of dielectric material. An outer layer of wire braid is disposed around an outermost layer of dielectric material that is used for grounding and/or shielding. An outer jacket is disposed around the outer layer of wire braid for encasing the transmission cable. The extruded member may comprise a thermoplastic rubber extrusion, for example. The coolant path through the transmission cable is internally supported by means of the extruded member to assure uniform flexibility, maintain tangential magnetic flux, and eliminate kinking and collapse of the flow path. The transmission cable is designed for charging propulsion batteries of an electric vehicle at extremely high charge rates. The charging system includes an external power source and off-vehicle inverter for providing charging current to the propulsion batteries by way of a charge port and a rectification/filter circuit in the electric vehicle. The transmission cable is coupled between the charge port and the rectification/filter circuit. A cooling system is coupled to the transmission cable that has a radiator for cooling coolant, a manifold, a pump that pumps the coolant, and a reservoir for storing excess coolant. The coolant is pumped from the cooling system through the transmission cable to cool it. The transmission cable 20 is capable of transferring 120 kW @334 Amps RMS @75 KHz.

Claims

1. A charging system for an electric vehicle, said system comprising:

a power source for supplying power;

an off-vehicle inverter for providing charging current that is used to charge propulsion batteries of the electric vehicle;

a charge port disposed on the electric vehicle that is coupled to the off-vehicle inverter;

a liquid-cooled transmission cable coupled between the charge port and the propulsion batteries of the electric vehicle, that comprises

a central tube that is used to carry coolant;

an extruded member disposed within the central tube;

a plurality of layers of coaxial tubular wire braid disposed around the central tube that are used to carry charging current and that each layer thereof is separated by a layer of dielectric material;

an outer layer of wire braid disposed around an outermost layer of dielectric material that is used for grounding and shielding; and

an outer jacket disposed around the outer layer of wire braid;

a cooling system coupled to the transmission cable for pumping coolant therethrough to cool the transmission cable, that comprises;

a radiator for cooling coolant;

a manifold coupled to an output of radiator;

a pump coupled to the manifold that pumps coolant through the cooling system; and

a reservoir coupled to the manifold and the radiator for storing excess coolant.

2. The charging system of claim 1 wherein the extruded member comprises a thermoplastic robber extrusion.

3. The charging system of claim 1 wherein the extruded member comprises a thermoplastic robber extrusion in the form of a five-pointed star.

5. The transmission cable of claim 1 wherein the extruded member comprises a thermoplastic rubber extrusion.

6. The transmission cable of claim 1 wherein the extruded member comprises a thermoplastic rubber extrusion in the form of a five-pointed star.

4. A transmission cable comprising:

a central tube that is used to carry coolant;

an extruded member disposed within the central tube;

a plurality of layers of coaxial tubular wire braid disposed around the central tube that are used to carry charging current and that each layer thereof is separated by a layer of dielectric material;

an outer layer of wire braid disposed around an outermost layer of dielectric material that is used for grounding and shielding; and

an outer jacket disposed around the outer layer of wire braid.