# US 2019/0168622 A1 · Hybrid powertrain system and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0168622 A1 - Document ID: US20190168622A1 - Status: Published application - Kind: A1 - Application number: 16/324,268 - Filed: 2017-08-10 - Published: 2019-06-06 - Earliest claimed: 2016-08-10 - Assignees: Pegasus Aeronautics Corporation - Applicants: Pegasus Aeronautics Corporation - Inventors: Matthew McRoberts; Joseph Kinsella; John Biskey; Carl Engelmann - Web page: https://patentgrep.com/patent/US20190168622A1 ## CPC - B60L 50/15: with additional electric power supply (with capacitors charged by engine-driven generators B60L50/40; with batteries charged by engine-driven generators B60L50/61) - B60L 15/2045: {for optimising the use of energy} - B60L 50/16: with provision for separate direct mechanical propulsion - B60W 20/00: Control systems specially adapted for hybrid vehicles {(hybrid vehicle design, B60K6/00; electric vehicles B60L)} - H02J 7/1492: {by means of controlling devices between the generator output and the battery} - B60L 2200/10: Air crafts - B64D 27/026: {comprising different types of power plants, e.g. combination of a piston engine and a gas-turbine (Hybrid electric aircraft B64D27/33)} - B64D 31/18: for hybrid-electric power plants - B64D 2221/00: Electric power distribution systems onboard aircraft - H02J 7/1438: {in combination with power supplies for loads other than batteries} - Y02T 10/62: Hybrid vehicles - Y02T 10/70: Energy storage systems for electromobility, e.g. batteries - Y02T 10/92: Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles - B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES - B60W: CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A hybrid powertrain system and method includes a prime mover driving a generator/motor to produce an AC power output. The AC power output is applied to a rectifier which is controlled to transform the applied AC power to DC power to supply a DC Power bus at a selected voltage and current. An energy storage device is also connected to the DC power bus and the current flow between the energy storage device and the DC power bus is monitored and compared to preselected values and the results of that comparison are used to alter the operation of the rectifier to increase or decrease, as needed, the current provided to the DC power bus as electrical loads on the DC power bus change. ## Claims ### Claim 1 A hybrid powertrain system comprising: an energy storage device; a prime mover operable to combust a fuel and produce a rotational output; an engine controller controlling the operating parameters of the prime mover, including at least its operating speed; a generator/motor operable, in a first state, to produce an electrical alternating current when rotated by the rotational out of the prime mover and operable, in a second state, to produce a rotational output to rotate the prime mover when provided with an electrical alternating current input; a rectifier operable in a first state to convert the electrical alternating current produced by the generator/motor into a direct current at a selected voltage and to provide that direct current to a power bus to the energy storage device is connected and operable in a second state to invert direct current energy provided from the energy storage device into an alternating current which can be provided to the generator/motor; and a generator control unit operable to select the state of the rectifier and to select the voltage of the direct current provided to the power bus. ### Claim 2 (depends on 1) The hybrid powertrain system of claim 1 wherein the energy storage device is a battery. ### Claim 3 (depends on 1) The hybrid powertrain system of claim 1 wherein the prime mover is an internal combustion engine. ### Claim 4 (depends on 1) The hybrid powertrain system of claim 1 wherein the prime mover is a gas turbine. ### Claim 5 (depends on 1) The hybrid powertrain system of claim 1 wherein the generator/motor comprises at least one three phase brushless direct current motor. ### Claim 6 (depends on 1) The hybrid powertrain system of claim 1 wherein the rectifier is an active rectifier. ### Claim 7 (depends on 1) The hybrid powertrain system of claim 1 wherein the rectifier comprises a passive rectifier, a power inverter and a DC-DC power converter. ### Claim 8 (depends on 3) The hybrid powertrain system of claim 3 wherein the engine controller receives at least an input representing the rotational speed of the prime mover and provides control signals including at least ignition timing, throttle position and fuel/air mixture to the prime mover. ### Claim 9 (depends on 1) The hybrid powertrain system of claim 1 wherein the generator control unit monitors the flow of direct current between the power bus and the energy storage device when the rectifier is in the first state and adjusts the operation of the active rectifier to select an output voltage such that the monitored current flow is substantially the same as a preselected target current flow. ### Claim 10 (depends on 5) The hybrid powertrain system of claim 5 wherein, in response to a command received when the prime mover is not operating, the generator control unit is operable to place the rectifier into the second state to invert direct current power from the energy storage device to an alternating current energy provided to the generator/motor causing the generator/motor to rotate the prime mover and the engine controller operating to start the prime mover. ### Claim 11 (depends on 1) The hybrid powertrain system of claim 1 wherein at least two electrical loads are supplied from the power bus. ### Claim 12 (depends on 9) The hybrid powertrain system of claim 9 wherein the operation of the prime mover can be suspended for a selected period of time, during which power is supplied to the power bus from the energy storage device, after which alternating current power, inverted from the direct current power from the energy storage device by the active rectifier, is applied to the generator/motor to rotate the prime mover and the engine control unit operates to restart the prime mover. ### Claim 13 (depends on 12) The hybrid powertrain system of claim 12 wherein, after restarting the prime mover, the active rectifier operates in the first state to convert alternating current produced by the generator/motor to direct current provided to the power bus. ### Claim 14 (depends on 13) The hybrid powertrain system of claim 13 wherein the target current flow is set to a value required to substantially recharge the energy stored in the energy storage device within a selected timeframe. ### Claim 15 A method of operating a hybrid powertrain including a prime mover which combusts a fuel, and engine control unit operable to control the prime mover, a generator/motor connected to the prime mover, a rectifier electrically connected between the generator/motor and a direct current power bus, a generator control unit operable to control the rectifier and an energy storage device connected to the direct current power bus, comprising the steps of: (i) receiving a signal to start the powertrain; (ii) the generator control unit configuring the rectifier to invert direct current power supplied to the power bus by the energy storage device into alternating current power; (iii) providing the alternating current power to the generator/motor to rotate the prime mover; (iv) the engine control unit starting the prime mover and the prime mover operating the generator/motor; (v) the generator control unit configuring the rectifier to rectify the alternating current, produced by the rotation of the generator/motor, to a direct current at a selected voltage and providing that direct current to the direct current power bus; and (vi) the generator control unit monitoring the current flow between the energy storage device and direct current power bus and adjusting the operation of the rectifier to alter the voltage of the rectified direct current provided to the direct current power bus such that the monitored current flow is substantially equal to a preselected value. ### Claim 16 (depends on 13) The method of operating a hybrid powertrain according to claim 13 wherein the engine control unit is further operable to maintain the operating speed of the prime mover substantially at a selected value. ### Claim 17 (depends on 16) The method of operating a hybrid powertrain according to claim 16 wherein the selected value is predefined for the prime mover. ### Claim 18 (depends on 14) The method of operating a hybrid powertrain according to claim 14 wherein the selected value is determined algorithmically by the engine control unit to improve fuel efficiency of the prime mover. ### Claim 19 (depends on 15) The method of operating a hybrid powertrain according to claim 15 further comprising the steps of: (a) upon receipt of a first command, stopping operation of the prime mover; (b) transferring power from the energy storage device to the direct current power bus to power electrical load attached thereto; (c) upon receipt of a second command, configuring the rectifier to invert power from the direct current power bus into alternating current power and supplying that alternating current power to the generator/motor to rotate the prime mover; (d) restarting the prime mover; and (e) configuring the rectifier to convert the alternating current produced by the generator/motor into direct current power provided to the direct current power bus.