Patent Publication Number: US-2020277061-A1

Title: Aircraft having hybrid-electric propulsion system with electric storage located in fuselage

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application No. 62/812,821 filed Mar. 1, 2019 the contents of which are incorporated by reference herein in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present disclosure relates to an aircraft having a hybrid-electric propulsion system, and more particularly, to an aircraft having a hybrid-electric propulsion system with batteries that are located in the fuselage of the aircraft. 
     2. Description of Related Art 
     Aircraft engines vary in efficiency and function over a plurality of parameters, such as thrust requirements, air temperature, air speed, altitude, and the like. Aircraft require the most thrust at take-off, wherein the demand for engine power is the heaviest. However, during the remainder of the mission, the aircraft engines often do not require as much thrust as during take-off. The size and weight of the engines allows them to produce the power needed for take-off, however after take-off the engines are in effect over-sized for the relatively low power required to produce thrust for cruising in level flight. 
     The conventional techniques have been considered satisfactory for their intended purpose. However, there is an ever present need for improved aircraft engines. This disclosure provides a solution for this need. 
     SUMMARY 
     An aircraft includes a fuselage defining a longitudinal axis between a forward end and an aft end. The aircraft includes an electrical system having an electric storage. The electric storage is positioned within the fuselage. 
     In accordance with some embodiments, the aircraft includes a hybrid electric propulsion system. The electrical system can be part of the hybrid electric propulsion system. The hybrid electric propulsion system can include a heat engine and/or an electric motor. The electrical system can be electrically coupled to the electric motor by way of a 1000-volt power bus. The electrical system and/or the electric storage can be operatively connected to the electric motor for receiving power therefrom or for supplying power thereto. The electrical system can be part of the hybrid electric propulsion system. The aircraft can include a 28V aircraft power system connected to the hybrid electric propulsion system for generating 28V of aircraft power supply for aircraft systems. 
     In some embodiments, the fuselage defines an interior cabin space. The interior cabin space can include a cabin floor. The electrical system can include a plurality of batteries. The plurality of batteries can be mounted to the cabin floor. The cabin floor can define a lower surface. The plurality of batteries can be mounted to the lower surface of the cabin floor. The electric motor controller can be mounted to the lower surface of the cabin floor. The electric motor controller can be mounted to at least one of the plurality of batteries, on a side of the batteries that is opposite from the cabin floor. The aircraft can include at least one airfoil extending laterally from the fuselage and a nacelle mounted to the airfoil. The electric motor can be mounted within the nacelle. The heat engine and the electric motor can be positioned within the nacelle. The aircraft can include a liquid fuel tank. The liquid fuel tank can be positioned at least one of inboard of or outboard of the nacelle. 
     In some embodiments, the fuselage includes at least one opening for providing fluid communication between an area outside of the fuselage and an electrical compartment in which the electric storage is positioned. The fuselage can include a venting line for fluid communication between an area outside of the fuselage and an electrical compartment in which the electric storage is positioned. The fuselage can include an electrical compartment in which the electric storage is positioned. The electrical compartment can be made from a material that is fire proof and/or fire resistant, and/or can include a lining that is fire proof and/or fire resistant. The electrical system can include an electric-motor controller. The fuselage can include an electrical system compartment in which the electric-motor controller and the electric storage are positioned. The electric storage can include at least one battery. The electric storage can include a plurality of batteries. The electric storage can include a liquid cooling circuit. The fuselage can include an electrical compartment in which the plurality of batteries are stored. The electrical compartment can include sections configured and adapted to contain a respective portion of the plurality of batteries. Each section can be divided from adjacent sections by a fire resistant and/or fire proof wall. The fuselage can include a floor, e.g. a cargo area/bay floor, wherein the plurality of batteries are mounted to the floor. 
     These and other features of the systems and methods of the subject disclosure will become more readily apparent to those skilled in the art from the following detailed description of the embodiments taken in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that those skilled in the art to which the subject disclosure appertains will readily understand how to make and use the devices and methods of the subject disclosure without undue experimentation, embodiments thereof will be described in detail herein below with reference to certain figures, wherein: 
         FIG. 1  is a schematic depiction of a top plan view of an embodiment of an aircraft constructed in accordance with the present disclosure, showing batteries positioned within the fuselage of the aircraft; 
         FIG. 2  is a schematic depiction of an embodiment of a hybrid electric propulsion system constructed in accordance with the present invention, showing the batteries operatively connected to the electric motor-controller and the electric motor; 
         FIG. 3  is a schematic depiction of a bottom plan view of a portion of the aircraft of  FIG. 1 , showing batteries positioned in the fuselage; 
         FIG. 4  is a schematic depiction of a perspective cut-away view of a portion of the aircraft of  FIG. 1 , showing batteries integrated with the cabin floor; 
         FIG. 5  is a schematic depiction of a cut-away view of a portion of the aircraft of  FIG. 1  as viewed from a bottom of the fuselage, showing the electric-motor controller mounted in the fuselage; 
         FIG. 6  is a schematic depiction of a perspective view of a portion of the electrical compartment constructed in accordance with the present disclosure, where the electrical compartment is integrated with the cabin floor, showing a portion of the cabin floor cut-away to show batteries; 
         FIG. 7  is a schematic depiction of a perspective cut-away view of a portion of an alternative embodiment of an aircraft constructed in accordance with the present disclosure, showing the electric motor controller underneath the batteries; 
         FIG. 8  is a schematic depiction of a bottom cut-away view of a portion of an alternative embodiment of an aircraft constructed in accordance with the present disclosure, showing the electric-motor controller mounted in the nacelle and a liquid cooling circuit; and 
         FIG. 9  is a schematic depiction of a portion of an alternative embodiment of an aircraft constructed in accordance with the present disclosure, showing a plurality of batteries mounted on top of a cabin floor. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Reference will now be made to the drawings wherein like reference numerals identify similar structural features or aspects of the subject disclosure. For purposes of explanation and illustration, and not limitation, a partial view of an exemplary embodiment of an aircraft constructed in accordance with the present disclosure is shown in  FIG. 1  and is designated generally by reference character  10 . Other embodiments of aircraft  10  in accordance with the disclosure, or aspects thereof, are provided in  FIGS. 2-9 , as will be described. The systems and methods described herein can be used to provide hybrid propulsion, e.g., for improving fuel efficiency in aircraft. Moreover, embodiments described herein can readily apply to all-electric aircraft, or the like. 
     As shown in  FIGS. 1-2 , an aircraft  10  includes a fuselage  20  defining a longitudinal axis A between a forward end  30  and an aft end  40 . Airfoils  50   a  and  50   b  laterally extend from the fuselage  20 . Each airfoil  50   a  and  50   b  includes a respective nacelle  122   a  and  122   b  mounted to thereto. The aircraft  10  includes a hybrid electric propulsion system  100 , portions of which are disposed in first nacelle  122   a.  An electrical system  101  is part of the hybrid electric propulsion system  100 . 
     With continued reference to  FIGS. 1-2 , the hybrid electric propulsion system  100  includes a heat engine  104 , e.g. a thermal engine, and an electric motor  106 , which on their own or together drive an air mover  105 , e.g. a propeller, fan or the like, by way of a reduction gear box  107  and shaft  111 . Air movers  105  are not shown in  FIG. 1 , but it is contemplated that each nacelle  122   a  and  122   b  would include a respective air mover  105  mounted on their forward facing hubs  131 . Reduction gear box  107  has an input  109   a  for heat engine  104  and an input  109   b  for electric motor  106 . Those skilled in the art will also readily appreciate that a clutch can be disposed between reduction gear box  107  and the heat engine  104  and another clutch can be disposed between electric motor  106  and reduction gear box  107 . The aircraft  10  also includes liquid fuel tanks  124 . While fuel tanks  124  are shown inboard of their respective nacelles  122   a  and  122   b,  those skilled in the art will readily appreciate that the liquid fuel tanks  124  can be positioned outboard of their respective nacelles  122   a/   122   b,  or a combination of inboard and outboard of their respective nacelles  122   a/   122   b.    
     It is contemplated that heat engine  104  could be a heat engine of any type, e.g., a gas turbine, spark ignited, diesel, rotary or reciprocating engine of any fuel type and with any configuration of turbomachiney elements, either turbocharger, turbosupercharger, supercharger and exhaust recovery turbo compounding, either mechanically, electrically, hydraulically or pneumatically driven. 
     With continued reference to  FIGS. 1-3 , the electrical system  101  includes an electric storage  103  that includes a battery bank, or the like. The storage  103  is made up of a plurality of batteries  102 . Batteries  102  can be rechargeable batteries. The electric storage  103  is positioned within the fuselage  20 . The electrical system  101 , e.g. an electric motor controller  121  and the storage  103 , is electrically coupled to the electric motor  106  by way of a high voltage power bus  123 . High voltage power bus  123  can be for 500 V or greater, e.g. a range from 890-1000 V, or higher. The high voltage power bus  123  is bi-directional, meaning power can go to electric-motor  106  from electric-motor controller  121  and from electric-motor  106  to electric-motor controller  121 . The high voltage power bus  123  extends from electric motor controller  121 , up the cabin wall, into a wing space above the fuselage  20 , and extends outward to connect to an electric motor  106 . If, like in  FIG. 8 , the electric motor controller  121  is positioned in the nacelle  122   a,  a conductor or bus  141  can extend from the electric storage  103 , up the cabin wall, into a wing space above the fuselage  20 , and outwardly to connect to the electric motor controller  121 . The electrical system  101  and the electric storage  103  are operatively connected to the electric motor  106  for receiving power therefrom or for supplying power thereto. 
     The electric motor controller  121  is positioned between electric motor  106  and electric storage  103 . It is contemplated that an electrical distribution system or battery management system can be positioned within the storage  103 , or between storage  103  and the electric-motor controller  121 . The electrical distribution system and/or battery management system is configured for managing the electrical power from the power storage  103 , e.g. the batteries  102 , to the electric-motor  106 . A separate conductor or bus  141  connects electric storage  103  to electric motor controller  121 . The aircraft  10  includes a 28V aircraft power system  135  connected to the hybrid electric propulsion system  100  for generating 28V of aircraft power supply for aircraft systems via output  139 . 
     In some embodiments, the electrical system  101  also includes a separate electrical storage  103 , e.g. a battery bank  119 , outside of the batteries  102  integrated with the cabin floor  112 . Battery bank  119  can include a plurality of batteries  102  stacked vertically and horizontally and, in  FIG. 3 , is positioned in an aft portion of fuselage  20 . Those skilled in the art will readily appreciate that battery bank  119  can be positioned in other locations as well. Battery bank  119  is also connected by way of bus  141  to the electrical storage  103  in the cabin floor  112  and the electric-motor controller. 
     As shown in  FIGS. 2 and 5 , the batteries  102  are operatively connected to the electric motor  106  for receiving power therefrom or for supplying power thereto by way of an electric-motor controller  121 . It is also contemplated that batteries  102  are connected to one or more inverter/rectifier components (for example, positioned between storage  103  and electric motor  106 ) for supplying power from the storage  103  to drive the electric motor  106 , or, in an energy recovery mode, to store into the storage  103  energy generated by driving the electric motor  106  in a generator mode 
     As shown in  FIGS. 4-5 , the fuselage  20  defines an interior cabin space  110 . The interior cabin space  110  includes a cabin floor  112  and at least one passenger seat  137  positioned on the cabin floor  112 . The plurality of batteries  102  are mounted to a lower surface  114  of the cabin floor  112  and are at least partially contained within an electrical system compartment  120 . Electrical system compartment  120  is similarly integrated with cabin floor  112 , as shown in  FIG. 6 . However, those skilled in the art will readily appreciate that batteries  102  can be integrated on their own without compartment  120  (similar to what is shown in  FIG. 4 ). Those skilled in the art will also readily appreciate that floor integration is not limited to the cabin floor  112  and that batteries can be integrated into a floor of the cockpit, cargo area, or the like (above and/or below the floor), or other suitable location. The electric motor controller  121  is mounted to the lower surface  114  of the cabin floor  112 , similar to the batteries  102 . The integration of the batteries  102  and compartment  120  with cabin floor  112  provides for a space-conscious solution to storing the electrical power needed to drive hybrid-electric propulsion system  100 . While shown mounted to the lower surface  114  of the cabin floor  112 , one skilled in the art will readily appreciate that electric motor controller can be positioned in a variety of suitable locations throughout the fuselage  20 . For example, electrical system compartment  120 , in some embodiments, also includes the electric-motor controller  121 . In some embodiments, as shown in  FIG. 7 , the electric motor controller  121  is mounted to at least one of the plurality of batteries  102 , on a side of the batteries  102  that is opposite from the cabin floor  112 . In another embodiment, as shown in  FIG. 8 , the electric motor controller  121  is mounted in the nacelle  122   a.    
     As shown in  FIGS. 3 and 6 , the fuselage  20  includes an aft vent opening  128  defined between the area  118  outside of the fuselage  20  and corresponding openings  115  and  127  in the electrical compartment  120 . The vent opening  128  is in fluid communication with opening  127  of compartment  120  between the area  118  outside of the fuselage  20  and the electrical compartment  120  where the batteries  102  are positioned. Electrical compartment  120  is in fluid communication with a venting line  122 . The venting line  122  provides fluid communication between the electrical compartment  120  and the area  118  outside of the fuselage  20  via vent opening  128 . Venting can be integrated within the cabin pressurization system including using check valves (one-way valves) to prevent return flow into cabin (e.g. a check valve could be posisioned on venting line  122 . Air from electrical compartment  120  is vented out of openings  115  and/or  127  to venting line  122 , as indicated schematically by arrow  129 . Cabin floor  112  can be divided into one or more panels  112   a,    112   b  or  112   c,  each panel can include one or more corresponding batteries  102  mounted to thereto. 
     Vent opening  128  allows heat, fumes, or the like to be dissipated from the electrical storage  103 , e.g. the group of batteries  102 , in compartment  120 . Vent opening  128  (and/or corresponding openings  115  and/or  127 , described below) can include fire detection and/or fire extinguishing methods and systems. It is also contemplated that heat dissipated from electrical storage  103  can be used for anti-ice or de-icing, or general heating of the aircraft  10  and its components (e.g. cabin, etc.). The heat can be directed to a given area as needed, directly, by way of heat exchanger, or the like. 
     As shown in  FIG. 6 , electrical compartment  120  includes a fire resistant and/or proof lining  125 . It is also contemplated that in lieu of or in addition to the lining  125 , each compartment  120  can be made from a fire proof and/or fire resistant material, or be constructed in another suitable fire resistant and/or proof configuration. In  FIG. 6 , for sake of clarity, only some of batteries  102  are shown. Electric motor controller  121 , also not shown for sake of clarity, would similarly be positioned in electrical compartment  120  to batteries  102 . The electrical compartment  120  includes sections  130  configured and adapted to contain a respective portion of the plurality of batteries  102 . Each section  130  is divided from adjacent sections  130  by a fire resistant and/or proof wall  132 . Each section  130  is configured and adapted to contain a respective portion of the plurality of batteries  102 . 
     With reference to  FIG. 8 , in accordance with another embodiment, the aircraft  10  includes a liquid cooling circuit  136  that is configured and adapted to flow through compartment  120  in between batteries  102  to provide cooling. Liquid cooling circuit  136  can be supplied with coolant via a coolant system that is on-board aircraft  10 , or can be fluidly connected to a coolant system on ground, for example, during recharging on-ground. The liquid cooling circuit can be connected to a ground cart that includes the remaining portions of the cooling system (e.g. pump, coolant, etc.) or it can be contained within aircraft  10 . If contained in aircraft  10 , various coolant system components, such as a radiator, heat exchanger or the like, may be included. Aircraft  10  is substantially the same as aircraft  10  of the other figures except for the inclusion of liquid cooling circuit  136  and the position of electric motor controller  121  (described above). The liquid cooling circuit  136  and/or the position of electric motor controller  121  can be incorporated into the embodiments of aircraft  10  described and shown in other figures, e.g.  FIGS. 1-7 , as needed. 
     As shown in  FIG. 9 , an alternative embodiment of aircraft  10  is shown. Aircraft  10  of  FIG. 9  is substantially the same as aircraft  10  of  FIGS. 1-7  except that a battery  102  is mounted on a top surface  113  of a cabin floor  112 . The interior cabin space  110  includes the cabin floor  112  and at least one passenger seat  137  positioned on the battery  102 , which are disposed on top of the cabin floor  112 . In essence, the battery  102  essentially becomes the floor that passengers would walk on. While shown and described as a singular battery, those skilled in the art will readily appreciate that a plurality of batteries  102  can be positioned on top of cabin floor  112 . It is contemplated that batteries  102  could be contained in a compartment, similar to compartment  120 , even if on top of cabin floor  112 . An electric motor controller, not shown, can be similar to electric-motor controller  121 , and can be similarly mounted on top of cabin floor  112 , or elsewhere in the fuselage or aircraft. Those skilled in the art will readily appreciate that a combination of batteries  102  can be positioned above and/or below the floor. 
     The methods and systems of the present disclosure, as described above and shown in the drawings provide for hybrid-electric and/or electric propulsion systems with superior properties including improved energy storage and use of hybrid heat engine and electric motor power. While the apparatus and methods of the subject disclosure have been shown and described with reference to certain embodiments, those skilled in the art will readily appreciate that change and/or modifications may be made thereto without departing from the scope of the subject disclosure.