# US 12,113,466 B2 · Multi-harmonic field oriented control for poly-phase motor/generator systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,113,466 B2 - Document ID: US12113466B2 - Status: Granted - Kind: B2 - Application number: 17/645,989 - Filed: 2021-12-26 - Published: 2022-06-30 - Granted: 2024-10-08 - Earliest claimed: 2020-12-27 - Assignees: Quantentech Limited - Applicants: Quantentech Limited - Inventors: Hengchun Mao - Web page: https://patentgrep.com/patent/US12113466B2 ## CPC - H02P 21/10: Direct field-oriented control; Rotor flux feed-back control - H02P 27/08: with pulse width modulation - H02K 3/28: Layout of windings or of connections between windings (windings for pole-changing H02K17/06, H02K17/14, H02K19/12, H02K19/32) - H02P 21/22: Current control, e.g. using a current control loop - H02P 2207/01: Asynchronous machines - H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) ## Abstract A method includes configuring a motor drive system with a motor/generator and a plurality of inverters coupled to the motor/generator, configuring a plurality of active harmonic planes to generate a torque on each of the active harmonic planes, and applying a harmonic plane synchronization mechanism to the plurality of active harmonic planes so that torque components and magnetizing components of currents are controlled in coordination on different active harmonic planes to output a desired torque from the motor/generator. ## Claims ### Claim 1 A method comprising: configuring a motor drive system with a motor/generator and a plurality of inverters coupled to the motor/generator; configuring a plurality of active harmonic planes to generate a torque on each of the active harmonic planes; and applying a harmonic plane synchronization control mechanism to the plurality of active harmonic planes so that torque components and magnetizing components of currents are controlled in coordination on different active harmonic planes to output a desired torque from the motor/generator. ### Claim 2 (depends on 1) The method of claim 1, wherein: a plurality of windings of the motor/generator is so configured that a pole number of the motor/generator can be adjusted by changing a phase shift between currents in adjacent windings. ### Claim 3 (depends on 1) The method of claim 1, further comprising: injecting a higher order harmonic to a magnetizing component of motor/generator currents through a saturation alleviation block to avoid or reduce a magnetic saturation in a region of the motor/generator; and injecting another harmonic current at the same order to a torque component of the motor/generator to generate a torque in a corresponding harmonic plane. ### Claim 4 (depends on 1) The method of claim 1, further comprising: adding a harmonic of a higher order into voltages of windings of the motor/generator through duty cycle control; and controlling harmonic currents at the same order such that a torque is generated at a corresponding harmonic plane. ### Claim 5 (depends on 1) The method of claim 1, wherein: the motor/generator is a synchronous machine, and wherein a harmonic current is added in response to a harmonic at the same order in the flux in a stator, an air gap, or a rotor of the motor/generator. ### Claim 6 (depends on 1) The method of claim 1, further comprising: detecting magnetizing components of the currents in a plurality of harmonic planes; and adjusting a torque component of the currents in a harmonic plane according to a magnetizing component in the same harmonic plane. ### Claim 7 (depends on 1) The method of claim 1, further comprising: during a transition, gradually reducing a magnetizing current reference in a first harmonic plane and gradually increasing a magnetizing current reference in a second harmonic plane, wherein a total torque of the motor/generator is maintained approximately constant. ### Claim 8 (depends on 1) The method of claim 1, further comprising: configuring the motor/generator to operate in a first operating mode with a first dominant harmonic plane and a first number of pole pairs; and configuring the motor/generator to operate in a second operating mode with a second dominant harmonic plane and a second number of pole pairs, wherein during a transition from the first operating mode to the second operating mode, a pole number change of the motor/generator is implemented as torque and magnetizing current reference changes on the first and second dominant harmonic planes. ### Claim 9 (depends on 1) The method of claim 1, further comprising: during a transition, reducing a first magnetizing current in a first harmonic plane and increasing a second magnetizing current in a second harmonic plane in a non-linear manner. ### Claim 10 (depends on 9) The method of claim 9, wherein: non-linear changes of the first magnetizing current and the second magnetizing current are trigonometric functions and have a modifier term which is approximately proportional to a rotor electromagnetic time constant of the motor/generator, and wherein nonlinear changes of a first torque current in the first harmonic plane and a second torque current in the second harmonic plane are configured such that a sum of torque produced in the first harmonic plane and in the second harmonic plane is approximately constant during the transition. ### Claim 11 (depends on 1) The method of claim 1, further comprising: during a fast transition, adding a modifier formed by a time-derivative term of a desired magnetic linkage to a corresponding magnetizing component reference on a harmonic plane, wherein the modifier is proportional to an electromagnetic time constant of a rotor of the motor/generator, so a torque generated in the harmonic plane follows a desired pattern. ### Claim 12 (depends on 1) The method of claim 1, further comprising: during a transition, changing a harmonic current reference in a d-axis gradually, wherein a q-axis harmonic current reference in a decreasing transition is maintained constant until the end of the transition, and a change of the q-axis harmonic current reference in an increasing transition is imposed at a beginning of the transition. ### Claim 13 (depends on 1) The method of claim 1, wherein: the motor/generator is an inductor machine; and the harmonic plane synchronization control mechanism is a slip synchronization to coordinate a reference of d-axis component of current and a reference of q-axis component of current on multiple harmonic planes among the plurality of active harmonic planes. ### Claim 14 A system comprising: a motor/generator having a plurality of windings, a rotor and a stator magnetically coupled to the rotor; a plurality of power converters connected to respective windings, wherein the plurality of power converters is configured to control currents of the plurality of windings; and a controller configured to configure a plurality of harmonic currents in a plurality of active harmonic planes to generate a torque on each of the plurality of active harmonic planes, and apply a harmonic plane synchronization control mechanism to the plurality of harmonic currents in different harmonic planes so that current control on different harmonic planes is coordinated to output a desired torque from the motor/generator. ### Claim 15 (depends on 14) The system of claim 14, wherein the controller comprises a multi-harmonic Park and Clarke transform block configured to: receive a plurality of phase currents of the motor/generator; and convert the plurality of phase currents into d-q frame variables at different harmonic frequencies. ### Claim 16 (depends on 15) The system of claim 15, wherein the controller comprises a multi-harmonic field oriented control block configured to: generate dominant current references based on d-q frame variables in a dominant harmonic plane; and generate a plurality of current references on the different harmonic planes through a slip synchronization determined by the dominant current references based on a field-oriented control principle. ### Claim 17 (depends on 14) The system of claim 14, wherein: the motor/generator is an induction motor; and the number of poles and the number of phases of the motor/generator are dynamically reconfigurable. ### Claim 18 A method comprising: configuring a motor drive system with a motor/generator and an inverter, wherein: the motor/generator has a plurality of windings arranged into a plurality of winding groups; and the inverter has a plurality of power converter groups, and wherein each power converter group is configured to control currents of a winding group; configuring a plurality of harmonic currents in a plurality of active harmonic planes to generator a torque on each active harmonic plane; and applying a harmonic plane synchronization control mechanism to the plurality of active harmonic planes so that current control on different harmonic planes is coordinated to output a desired torque from the motor/generator. ### Claim 19 (depends on 18) The method of claim 18, further comprising: dynamically adjusting the number of poles of the motor drive system by adjusting current references in different active harmonic planes. ### Claim 20 (depends on 18) The method of claim 18, further comprising: during a transition, gradually reducing harmonic currents in a first harmonic plane and gradually increasing harmonic currents in a second harmonic plane, wherein a total torque of the motor/generator is maintained approximately constant.