# US 12,771,274 B2 · Motor driver > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,771,274 B2 - Document ID: US12771274B2 - Status: Granted - Kind: B2 - Application number: 18/651,235 - Filed: 2024-04-30 - Published: 2024-08-22 - Granted: 2026-10-20 - Earliest claimed: 2021-11-02 - Assignees: Denso Corporation - Applicants: Denso Corporation - Inventors: Koki Nagura; Hideki Kabune - Web page: https://patentgrep.com/patent/US12771274B2 ## CPC - H02P 25/186: {whereby the speed is regulated by using a periodic interrupter (H02P25/30 takes precedence)} - H02P 27/06: using DC to AC converters or inverters (H02P27/05 takes precedence) - H02P 2201/07: DC-DC step-up or step-down converter inserted between the power supply and the inverter supplying the motor, e.g. to control voltage source fluctuations, to vary the motor speed - H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS ## Abstract A motor driver includes an inverter, a multiphase pre-driver circuit, a controller and motor relays. The inverter includes pairs of an upper-arm switching element and a lower-arm switching element being connected in series between a ground line and a power supply line, and supplies power to a multiphase motor by converting direct current power of a battery. The multiphase pre-driver circuit drives the upper-arm and lower-arm switching elements. The controller commands the multiphase pre-driver circuit to drive the switching elements, and controls electrical conduction from the inverter to the multiphase motor. The motor relays interrupt a current flowing from the multiphase motor to the inverter during an off state. The multiphase pre-driver circuit includes a charge pump. The motor relays are turned on by an output voltage of the charge pump during an operation of the charge pump in a situation apart from that the controller provides an instruction. ## Claims ### Claim 1 A motor driver comprising: an inverter including pairs of an upper-arm switching element and a lower-arm switching element, the pairs of the upper-arm switching element and the lower-arm switching element being provided for respective phases of a multiphase motor, the upper-arm switching element and the lower-arm switching element being connected in series between a ground line and a power supply line, the power supply line being connected to a battery of an electric vehicle, the battery having a voltage of 24 V or 48 V, the inverter configured to supply converted power to the multiphase motor by converting direct current power of the battery; a multiphase pre-driver circuit configured to be powered by a voltage supplied from the battery to drive the pairs of the upper-arm switching element and the lower-arm switching element included in the inverter, the multiphase pre-driver circuit including a charge pump configured to boost a voltage of the battery; a controller configured to control electrical conduction from the inverter to the multiphase motor via transmission of a drive signal to the multiphase pre-driver circuit; motor relays being semiconductor switching elements corresponding to the respective phases, each of which is configured to be turned off to interrupt a current flowing from the multiphase motor to the inverter, each of the motor relays being connected between an inter-arm connection node and a corresponding one of phase windings of the multiphase motor, the inter-arm connection node being a connection node between the upper-arm switching element and the lower-arm switching element, the charge pump having an output end connected to respective gates of the motor relays corresponding to the respective phases of the multiphase motor; at least one gate interruption switch configured to interrupt the output voltage supplied from the output end of the charge pump to the respective gates of the motor relays, in response to receiving an interruption signal as the instruction being provided from the controller; and a reverse connection protective relay connected to a freewheeling diode in parallel, the freewheeling diode configured to conduct a current flowing from the battery to the inverter, the reverse connection protective relay having a gate to which the output end of the charge pump is connected, the reverse connection protective relay configured to be turned off to interrupt a current flowing from the inverter to the battery, wherein the motor relays and the reverse connection protective relay are configured to be continuously turned on by an output voltage of the charge pump during an operation of the charge pump unless the controller provides an instruction to turn off the motor relays. ### Claim 2 (depends on 1) The motor driver according to claim 1, wherein: the at least one gate interruption switch is at least one of gate interruption switches; the gate interruption switches are provided for the respective phases of the multiphase motor; and the gate interruption switches are configured to interrupt the output voltage supplied from the output end of the charge pump to the respective gates of the motor relays, respectively, based on interruption signals as instructions that are separately provided from the controller and correspond to the respective phases of the multiphase motor. ### Claim 3 (depends on 1) The motor driver according to claim 1, further comprising: a step-down regulator connected between the multiphase pre-driver circuit and the battery, the step-down regulator configured to step down the voltage of the battery. ### Claim 4 (depends on 1) The motor driver according to claim 1, further comprising: an LC filter in which a capacitor and an inductor are connected, wherein the reverse connection protective relay is connected between the inductor and the multiphase pre-driver circuit. ### Claim 5 (depends on 1) The motor driver according to claim 1, wherein the charge pump is configured to apply the output voltage to turn on the motor relays without a driver circuit therebetween.