# US 12,762,965 B2 · Method for monitoring an energy level of an electrical energy source of a hybrid power plant for an aircraft > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,762,965 B2 - Document ID: US12762965B2 - Status: Granted - Kind: B2 - Application number: 18/950,823 - Filed: 2024-11-18 - Published: 2025-07-10 - Granted: 2026-10-13 - Earliest claimed: 2024-01-08 - Assignees: Airbus Helicopters - Applicants: Airbus Helicopters - Inventors: Guillaume Dumur; Jérémy Camus; Léonard Boudier; Jean-François Logeais; Mikaël Henaff - Web page: https://patentgrep.com/patent/US12762965B2 ## CPC - G08G 5/50: Navigation or guidance aids - B64D 27/33: Hybrid electric aircraft - B64D 27/357: using batteries - G08G 5/55: for a single aircraft - G08G: TRAFFIC CONTROL SYSTEMS (guiding railway traffic, ensuring the safety of railway traffic B61L; arrangement of road signs or traffic signals E01F9/00; radar or analogous systems, sonar systems, lidar systems specially adapted for traffic control G01S13/91, G01S15/88, G01S17/88; {radar or analogous systems, sonar systems, lidar systems specially adapted for anti-collision purposes G01S13/93, G01S15/93, G01S17/93}) - B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT ## Abstract A method for monitoring an energy level of an electrical energy source capable of delivering a reference electrical power PRef for a reference time period DTRef for a reference charge level NRef. Said source comprises at least one electrical energy storage device and several sensors. Said method comprises using the sensors to acquire parameters of the electrical energy source, then calculating a main consumption time period DTprin wherein the source is able to supply an electric current carrying the reference electrical power PRef, as a function of the parameters of the source. Next, a main display of main symbols indicating the main consumption time period DTprin is displayed in order to indicate to an operator how long the source can supply the reference electrical power PRef. ## Claims ### Claim 1 A method for monitoring an energy level of an electrical energy source, the electrical energy source being capable of delivering a reference electrical power for a predetermined reference time period for a predetermined reference charge level and comprising: at least one electrical energy storage device; at least one sensor; and a calculator, wherein the electrical energy source equips an aircraft comprising a hybrid power plant and a lift rotor rotated by the hybrid power plant via a mechanical transmission system, the hybrid power plant comprising at least one heat engine, at least one electric machine, and the electrical energy source electrically connected to the electric machine(s) via an electrical connection system; wherein the method comprises the following steps: acquiring at least one parameter of the electrical energy source via the sensor(s); calculating, by the calculator, a main consumption time period wherein the electrical energy source is able to supply an electric current carrying the reference electrical power, as a function of the parameter(s) of the electrical energy source; causing, by the calculator, a display unit to display a main display of main symbols indicating the main consumption time period; determining, by the calculator, at least one characteristic of the aircraft based on information received from at least one sensor or avionics system of the aircraft; estimating, by the calculator, at least one rate of sink and at least one distance that is reachable using only electrical energy that the electrical energy source can deliver as a function of the parameter(s) of the electrical energy source and the characteristic(s) of the aircraft; and causing, by the calculator, the display unit to display a descent display of descent symbols representing at least one trajectory of descent of the aircraft as a function of the rate of sink and the reachable distance. ### Claim 2 (depends on 1) The method according to claim 1, wherein the parameter(s) is/are chosen from a charge level, a temperature, and a level of ageing of the electrical energy source, and an electrical intensity and an electrical voltage of an electric current flowing in the electrical energy source, an internal resistance of the electrical energy source, an impedance of the electrical energy source, and a residual amount of the electrical energy source. ### Claim 3 (depends on 2) The method according to claim 2, wherein, when the electrical energy source comprises at least two electrical energy storage devices, the parameter(s) comprise(s) one or more parameters relating to each of the storage devices. ### Claim 4 (depends on 1) The method according to claim 1, wherein the method comprises estimating at least one additional consumption time period wherein the electrical energy source is able to supply an electric current carrying an additional electrical power different to the reference electrical power, as a function of the parameter(s) of the electrical energy source and the additional electrical power, and displaying an additional display of additional symbols indicating the additional consumption time period. ### Claim 5 (depends on 1) The method according to claim 1, wherein, during acquiring, a plurality of parameters of the electrical energy source are acquired, and the method comprises identifying a most penalizing parameter from among the acquired parameters, the main consumption time period being calculated for the most penalizing parameter during calculating. ### Claim 6 (depends on 5) The method according to claim 5, wherein identifying a most penalizing parameter among the acquired parameters comprises the following sub-steps: comparing the acquired parameters with respective thresholds, and estimating the most penalizing parameter as being the parameter exceeding with the greatest deviation in value or percentage the threshold corresponding thereto or the parameter having the smallest deviation in value or percentage from the threshold if none of the thresholds is exceeded. ### Claim 7 (depends on 1) The method according to claim 1, wherein, when performing the estimation, several rates of sink and several reachable distances are estimated, being associated respectively with several different electrical powers that the electrical energy source can deliver, and several trajectories of descent are displayed. ### Claim 8 (depends on 7) The method according to claim 7, wherein the method comprises determining a maximum reachable distance equal to the greatest of the reachable distances, the maximum reachable distance being associated with an optimal rate of sink and an optimal electrical power. ### Claim 9 (depends on 8) The method according to claim 8, wherein the method comprises localizing a current position of the aircraft and the descent symbols comprise at least one reachable distance, displayed superposed on a map of the surroundings of the aircraft, that can be reached from the current position of the aircraft, the displayed reachable distance(s) being chosen from the estimated reachable distance(s) and wherein the displayed reachable distance(s) comprises the maximum reachable distance and a reference reachable distance associated with the reference electrical power. ### Claim 10 (depends on 7) The method according to claim 7, wherein the method comprises localizing a current position of the aircraft and the descent symbols comprise at least one reachable distance, displayed superposed on a map of the surroundings of the aircraft, that can be reached from the current position of the aircraft, the displayed reachable distance(s) being chosen from the estimated reachable distance(s). ### Claim 11 (depends on 7) The method according to claim 7, wherein the method comprises selecting a trajectory chosen from the trajectories of descent and displaying an assistance display of descent symbols comprising an artificial horizon and a descent reference mark representative of the rate of sink corresponding to the chosen trajectory. ### Claim 12 (depends on 7) The method according to claim 7, wherein the method comprises selecting a trajectory chosen from the trajectories of descent and displaying an assistance display of descent symbols comprising a power indicator of the aircraft and a power reference mark representative of the electrical power corresponding to the chosen trajectory. ### Claim 13 (depends on 1) The method according to claim 1, wherein the trajectory or trajectories of descent comprise(s) a first slope according to the estimated rate of sink corresponding to a flight with electrical power supplied by the electrical energy source and a second slope at an autorotation rate of sink to the ground corresponding to a flight without driving power. ### Claim 14 (depends on 1) The method according to claim 1, wherein the method comprises a step of constructing the trajectory of descent and/or a step of determining a speed of descent of the aircraft associated with the estimated rate of sink and with the corresponding electrical power, and/or a step of calculating a consumption time period associated with the electrical power corresponding to the rate of sink. ### Claim 15 (depends on 1) The method according to claim 1, wherein the characteristic of the aircraft is chosen from a height in relation to the ground, a forward speed and a vertical speed of the aircraft. ### Claim 16 (depends on 1) The method according to claim 1, wherein the rate of sink and the reachable distance are corrected as a function of a wind speed experienced by the aircraft. ### Claim 17 (depends on 1) The method according to claim 1, wherein the rate of sink is determined by the calculator using aircraft-performance data stored in a memory of the calculator or in a memory connected to the calculator, the aircraft-performance data associating aircraft characteristics and electrical powers supplied by the electrical energy source to the at least one electric machine with corresponding rates of sink. ### Claim 18 (depends on 1) The method according to claim 1, wherein the trajectory of descent is constructed by the calculator to determine the reachable distance, the reachable distance being a horizontal distance between a current position of the aircraft and a destination point of the trajectory of descent on the ground. ### Claim 19 An electrical energy source for equipping an aircraft, the aircraft comprising a hybrid power plant and a lift rotor rotated by the hybrid power plant via a mechanical transmission system, the hybrid power plant comprising at least one heat engine and at least one electric machine, the electrical energy source being configured to be electrically connected to the at least one electric machine via an electrical connection system, the electrical energy source being capable of delivering a reference electrical power for a predetermined reference time period for a predetermined reference charge level, the electrical energy source comprising: at least one electrical energy storage device; at least one sensor; and calculator comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the calculator, when the electrical energy source equips the aircraft, to: acquire at least one parameter of the electrical energy source via the at least one sensor; calculate a main consumption time period wherein the electrical energy source is able to supply an electric current carrying the reference electrical power, as a function of the at least one parameter of the electrical energy source; cause a display unit of the aircraft to display a main display of main symbols indicating the main consumption time period; determine, based on information received from at least one sensor or avionics system of the aircraft, at least one characteristic of the aircraft; estimate at least one rate of sink and at least one distance that is reachable using only electrical energy that the electrical energy source can deliver as a function of the at least one parameter of the electrical energy source and the at least one characteristic of the aircraft; and cause the display unit to display a descent display of descent symbols representing at least one trajectory of descent of the aircraft as a function of the rate of sink and the reachable distance. ### Claim 20 An aircraft comprising: a hybrid power plant comprising at least one heat engine and at least one electric machine; a lift rotor rotated by the hybrid power plant via a mechanical transmission system; a display unit; an electrical energy source electrically connected to the at least one electric machine via an electrical connection system and capable of delivering a reference electrical power for a predetermined reference time period for a predetermined reference charge level, the electrical energy source comprising: at least one electrical energy storage device; at least one sensor; and calculator comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the calculator to: acquire at least one parameter of the electrical energy source via the sensor; calculate a main consumption time period wherein the electrical energy source is able to supply an electric current carrying the reference electrical power, as a function of the parameter of the electrical energy source; cause the display unit to display a main display of main symbols indicating the main consumption time period; determine, based on information received from at the least one sensor or avionics system of the aircraft, at least one characteristic of the aircraft; estimate at least one rate of sink and at least one distance that is reachable using only electrical energy that the electrical energy source can deliver as a function of the parameter of the electrical energy source and the characteristic of the aircraft; and cause the display unit to display a descent display of descent symbols representing at least one trajectory of descent of the aircraft as a function of the rate of sink and the reachable distance.