# US 2020/0395784 A1 · Polyphase contactless induction power transfer system for transferring electrical power across gap > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0395784 A1 - Document ID: US20200395784A1 - Status: Published application - Kind: A1 - Application number: 16/437,744 - Filed: 2019-06-11 - Published: 2020-12-17 - Earliest claimed: 2019-06-11 - Assignees: Raytheon Company - Applicants: Raytheon Company - Inventors: Stephen Kuznetsov - Web page: https://patentgrep.com/patent/US20200395784A1 ## CPC - H02J 3/30: using dynamo-electric machines coupled to flywheels - H02J 50/10: using inductive coupling - B60L 50/52: characterised by DC-motors - B60L 53/12: Inductive energy transfer - H02J 50/90: involving detection or optimisation of position, e.g. alignment - H02K 1/17: Stator cores with permanent magnets - H02K 41/025: Asynchronous motors - Y02E 60/16: Mechanical energy storage, e.g. flywheels or pressurised fluids - Y02T 10/70: Energy storage systems for electromobility, e.g. batteries - Y02T 10/7072: Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors - Y02T 90/14: Plug-in electric vehicles - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - 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 - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract An inductive power transfer system is used for transferring electrical power across a gap, such as an air gap or a liquid gap, such as to unmanned autonomous vehicles (UAVs). The power transfer system is a polyphase system that creates a travelling magnetic field in the air or liquid gap, implementing a resonant electro-magnetic (EM) field to allow larger gap separations and less precise alignments. The power transfer system may have a polyphase dynamoelectric machine attached to primary mechanical-inertial storage device with multiple stator and rotor ports connected to a polyphase traveling-wave inductive power transmitter apparatus. The system may be of use in transferring power to underwater vehicles in a subsea salt water environment. Such a power transfer system may part of a larger system for underwater power transfer, for instance at depths of at least 10 km, and/or at distances of 1 to 50 km. ## Claims ### Claim 1 A power transfer system comprising: a polyphase dynamoelectric machine, wherein the dynamoelectric machine includes multiple electrical ports, including primary and secondary electrical ports; a mechanical-inertial energy storage device coupled to the polyphase dynamoelectric machine; polyphase traveling-wave inductive power transmitters coupled to respective of the secondary ports; and polyphase travelling-wave power receivers inductively coupled to the transmitters, and providing electrical power to loads. ### Claim 2 (depends on 1) The power transfer system of claim 1, wherein the ports include a primary input port, and multiple secondary output ports; and wherein the polyphase traveling-wave inductive power transmitters are coupled to respective of the secondary output ports; and further comprising a DC-AC power converter coupled to the primary input port that derives power from a power generation source, through a transmission line configured to provide variable-frequency power to the primary input port. ### Claim 3 (depends on 2) The power transfer system of claim 2, wherein the polyphase dynamoelectric machine further includes respective electrical resonant circuits between the secondary output ports and the respective of the polyphase traveling-wave inductive power transmitters, configured to enhance power transfer efficiency to the transmitter. ### Claim 4 (depends on 1) The power transfer system of claim 1, wherein the mechanical-inertial energy storage device includes a flywheel that is operatively coupled to a rotor of the dynamoelectric machine, with the energy storage device configured to have substantially equal charge and discharge rates to and from the flywheel. ### Claim 5 (depends on 1) The power transfer system of claim 1, wherein the dynamoelectric machine and the mechanical-inertial energy storage device are fully bidirectional in power and energy flow, and capable of returning energy to a power generation source and capable of directing energy to loads coupled to the receivers. ### Claim 6 (depends on 1) The power transfer system of claim 1, wherein the induction transmitters accept input power over a range of frequencies, and create a traveling magnetic wave with a corresponding range of traveling speeds, to enable the transmitters to produce a controllable longitudinal propulsive force on the receivers. ### Claim 7 (depends on 6) The power transfer system of claim 6, wherein the induction transmitters each have at least four poles. ### Claim 8 (depends on 6) The power transfer system of claim 6, wherein the induction transmitters have a pole pitch of at least 15 cm (6 inches). ### Claim 9 (depends on 6) The power transfer system of claim 6, wherein the receivers are configured to use the longitudinal propulsive force to assist docking between the transmitters and the receivers. ### Claim 10 (depends on 1) The power transfer system of claim 1, wherein the dynamoelectric machine is a wound DC-field synchronous machine, with controllable excitation. ### Claim 11 (depends on 1) The power transfer system of claims 1, wherein the dynamoelectric machine is a permanent magnet synchronous machine. ### Claim 12 (depends on 1) The power transfer system of claim 1, wherein the dynamoelectric machine is a doubly-fed induction machine. ### Claim 13 (depends on 12) The power transfer system of claim 12, wherein the dynamoelectric machine is a wound DC-field synchronous machine, with controllable excitation; and further comprising an electrochemical energy storage device operatively coupled to the rotor, for providing variable-frequency excitation or direct-current excitation to the rotor. ### Claim 14 (depends on 1) The power transfer system of claim 1, wherein one of the receivers is a vehicle receiver that is part of a vehicle. ### Claim 15 (depends on 14) The power transfer system of claim 14, wherein the vehicle receiver is operatively coupled to an additional energy storage device, which serves to provide electrical power to one of the loads, in addition to the power provided by the vehicle receiver. ### Claim 16 (depends on 15) The power transfer system of claim 15, wherein the additional energy storage device includes a pulse forming network, which is configured to shape and control electrical pulses for power the one of the loads. ### Claim 17 (depends on 15) The power transfer system of claim 15, wherein the additional energy storage device includes an electrochemical energy storage device, which is configured to provide power to the one of the loads, and is rechargeable by the vehicle receiver. ### Claim 18 (depends on 14) The power transfer system of claim 14, wherein the coupling between the vehicle receiver and the one of the transmitters allows for bidirectional energy transfer in either direction across a liquid or gaseous gap. ### Claim 19 A method of electric power control between a power transfer system and a vehicle, the method comprising: inductively coupling, across a liquid or gaseous gap, a polyphase traveling-wave inductive power transmitter of the power transfer system, and a receiver of the vehicle; and providing power to one of the transmitter or the receiver, for transfer of the power to the other of the transmitter or the receiver; wherein the providing power to the one of the transmitter or the receiver includes providing power from a dynamoelectric machine that is electrically coupled to the transmitter; and further comprising providing bidirectional power to the dynamoelectric machine from a power source, and from the dynamoelectric machine to the power source, with excess energy from an energy storage device of the vehicle capable of being returned to the power source. ### Claim 20 A power transfer system comprising: a power source; a pair of polyphase dynamoelectric machines operatively coupled to the power source; and a pair of transmitter-receiver pairs operatively coupled to respective of the dynamoelectric machines; wherein each of the transmitter-receiver pairs includes: a polyphase traveling-wave inductive power transmitter; and a polyphase travelling-wave power receiver inductively coupled to the transmitter, and providing electrical power to loads.