# US 2021/0242816 A1 · Motor controller > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0242816 A1 - Document ID: US20210242816A1 - Status: Published application - Kind: A1 - Application number: 17/165,402 - Filed: 2021-02-02 - Published: 2021-08-05 - Earliest claimed: 2020-02-04 - Assignees: Denso Corporation - Applicants: Denso Corporation - Inventors: Yuuichi SEO; Hironori IWAMIYA; Hirokazu TOYODA - Web page: https://patentgrep.com/patent/US20210242816A1 ## CPC - H02P 25/22: Multiple windings; Windings for more than three phases - H02P 27/085: {wherein the PWM mode is adapted on the running conditions of the motor, e.g. the switching frequency} - H02K 11/33: Drive circuits, e.g. power electronics (H02K11/38 takes precedence) - H02P 6/16: Circuit arrangements for detecting position - 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 motor controller for controlling a drive of a motor having plural phase windings includes upper and lower arm circuits and a control unit. The control unit switchingly controls ON/OFF of switches of the upper and lower arm circuits, for sequentially switching an energized phase of the motor. Then, from among the plural switches, a switch forming an energization path to the energized phase is designated as an energized phase switch with the others of the plural switches being designated as non-energized phase switches. Further, from among the non-energized phase switches, a switch forming a path of a reflux current that accompanies the switching of the energized phase is designated as a reflux switch. Then, the control unit performs an ON control of the energized phase switch in addition to performing an ON control of the reflux switch. ## Claims ### Claim 1 A motor controller for controlling a drive of a motor having multiple phase windings, the motor controller comprising: a plurality of upper and lower arm circuits formed by a plurality of switches; and a control unit switching on/off states of the plurality of switches to sequentially switch an energized phase among a plurality of phases, wherein, among the plurality of switches, a switch or switches that form an energization path to the energized phase is designated as an energized phase switch or switches, and a switch or switches other than the energized phase switch is designated as a non-energized phase switch or switches, among the plurality of non-energized phase switches, a switch or a switches forming a path of a reflux current generated by the switching of the energized phase is designated as a reflux switch or switches, and the control unit controls the reflux switch or switches into an ON state in addition to controlling the energized phase switch or switches. ### Claim 2 (depends on 1) The motor controller of claim 1 further comprising: a current sensor detecting a magnitude of an electric current flowing through the energized phase, wherein an ON period for a turning ON of the reflux switch or switches is increased by the control unit when a detected value of the electric current is increased. ### Claim 3 (depends on 2) The motor controller of claim 2, wherein the control unit controls the reflux switch or switches to be in the ON state on condition that the ON period set according to the detected value is a predetermined time or more. ### Claim 4 (depends on 1) The motor controller of claim 1, wherein an ON period for a turning ON of the reflux switch or switches is set individually for each of the plurality of phases. ### Claim 5 (depends on 1) The motor controller of claim 1, further comprising: a passage timing detector detecting a passage timing at which an induced voltage in the winding whose phase is different from the energized phase or phases has crossed a reference voltage by rising or falling, wherein the control unit controls a switching timing for switching the energized phase or phases based on the passage timing detected by the passage timing detector, the control unit prohibits a reflection of the passage timing to the switching control in a mask period set to be longer than a reflux period in which the reflux current is generated, and a timing for ending the ON state of the reflux switch or switches is set to a timing before an end of the mask period. ### Claim 6 (depends on 1) The motor controller of claim 1, wherein a timing for ending the ON state of the reflux switch or switches is set to a timing after a reflux period during which the reflux current flows. ### Claim 7 (depends on 1) The motor controller of claim 1, wherein an ON-start timing of the reflux switch or switches is set at a same timing as the switching of the energized phase or phases. ### Claim 8 A motor controller comprising: a processor; and a non-transitory computer-readable storage medium including instructions, wherein the motor controller is configured to: acquire a motor current from a current sensor at a crossing of a phase voltage and reference voltage; determine a power supply pattern and a rotation direction of a motor; identify a reflux switch for a reflux current based on the power supply pattern and the rotation direction of the motor; set a mask period based on the motor current, such that the mask period>a reflux period; and set a reflux-ON period, such that the reflux-ON period