# US 12,015,312 B2 · Motor controller, motor and pump device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,015,312 B2 - Document ID: US12015312B2 - Status: Granted - Kind: B2 - Application number: 17/692,213 - Filed: 2022-03-11 - Published: 2022-09-22 - Granted: 2024-06-18 - Earliest claimed: 2021-03-16 - Assignees: Nidec Sankyo Corporation - Applicants: Nidec Sankyo Corporation - Inventors: Satoshi Tanimura; Takashi Yamamoto - Web page: https://patentgrep.com/patent/US12015312B2 ## CPC - H02K 11/33: Drive circuits, e.g. power electronics (H02K11/38 takes precedence) - F04D 13/06: the pump being electrically driven - F04D 25/06: the pump being electrically driven (F04D25/08 takes precedence) - F04D 29/40: Casings; Connections of working fluid {(bleed or by-pass valves F04D15/0011, F04D27/0215)} - F04D 29/669: {especially adapted for liquid pumps (F04D29/18 takes precedence)} - H02P 1/44: by phase-splitting with a capacitor - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS ## Abstract A motor controller includes a motor control part controlling a motor having a three-phase coil by a control signal, an inverter applying a drive voltage supplied from a power source to the three-phase coil based on an output signal from the motor control part, a drive voltage line supplying the drive voltage to the inverter, a common line electrically connected with a neutral point of the three-phase coil, an inductor electrically connected in series with the drive voltage line, a first capacitor between a portion between the inverter and the inductor in the drive voltage line and a ground, a second capacitor between a portion on an input side with respect to the first capacitor in the drive voltage line and the ground, and a third capacitor between the second capacitor and the ground. The common line is electrically connected between the second capacitor and the third capacitor. ## Claims ### Claim 1 A motor controller which controls a motor having a three-phase coil, the motor controller comprising: a motor control part which controls rotation of the motor by a control signal; an inverter which applies a drive voltage supplied from a driving power source to the three-phase coil based on an output signal from the motor control part; a drive voltage line which supplies the drive voltage to the inverter; a common line which is electrically connected with a neutral point of the three-phase coil; an inductor which is electrically connected in series with the drive voltage line; a first capacitor which is electrically connected between a portion between the inverter and the inductor in the drive voltage line and a ground; a second capacitor which is electrically connected between a portion on an input side with respect to the first capacitor in the drive voltage line and the ground; and a third capacitor which is electrically connected between the second capacitor and the ground; wherein the common line is electrically connected between the second capacitor and the third capacitor. ### Claim 2 (depends on 1) The motor controller according to claim 1, wherein when a capacitance of each of the second capacitor and the third capacitor is defined as C1, the C1 satisfies a following conditional expression: “0.047 μF≤C1≤0.33 μF”. ### Claim 3 (depends on 1) The motor controller according to claim 1, wherein the second capacitor is electrically connected between a portion on an input side with respect to the inductor in the drive voltage line and the ground. ### Claim 4 (depends on 3) The motor controller according to claim 3, wherein the second capacitor is electrically connected between a portion on an input side with respect to the inductor in the drive voltage line and the ground. ### Claim 5 (depends on 4) The motor controller according to claim 4, wherein when a capacitance of the first capacitor is defined as C2, the C2 satisfies a following conditional expression: “100 μF≤C2”. ### Claim 6 (depends on 5) The motor controller according to claim 5, further comprising: a control signal line configured to input the control signal into the motor control part, and a fourth capacitor which is electrically connected between the control signal line and the ground. ### Claim 7 (depends on 6) The motor controller according to claim 6, further comprising: a ferrite bead which is electrically connected in series with the control signal line in a portion on an input side with respect to the fourth capacitor in the control signal line; and a sixth capacitor which is electrically connected between a portion on an input side with respect to the ferrite bead in the control signal line and the ground. ### Claim 8 (depends on 6) The motor controller according to claim 6, further comprising: an FG output line configured to transmit a rotation number signal according to a rotation number of the motor to an external device; and a fifth capacitor which is electrically connected between the FG output line and the ground. ### Claim 9 (depends on 8) The motor controller according to claim 8, wherein when a capacitance of the fifth capacitor is defined as C3, the C3 satisfies a following conditional expression: “C3≤0.1 μF”. ### Claim 10 (depends on 1) The motor controller according to claim 1, wherein when a capacitance of the first capacitor is defined as C2, the C2 satisfies a following conditional expression: “100 μF≤C2”. ### Claim 11 (depends on 1) The motor controller according to claim 1, further comprising: a control signal line configured to input the control signal into the motor control part, and a fourth capacitor which is electrically connected between the control signal line and the ground. ### Claim 12 (depends on 11) The motor controller according to claim 11, further comprising: a ferrite bead which is electrically connected in series with the control signal line in a portion on an input side with respect to the fourth capacitor in the control signal line; and a sixth capacitor which is electrically connected between a portion on an input side with respect to the ferrite bead in the control signal line and the ground. ### Claim 13 (depends on 1) The motor controller according to claim 1, further comprising: an FG output line configured to transmit a rotation number signal according to a rotation number of the motor to an external device; and a fifth capacitor which is electrically connected between the FG output line and the ground. ### Claim 14 (depends on 13) The motor controller according to claim 13, wherein when a capacitance of the fifth capacitor is defined as C3, the C3 satisfies a following conditional expression: “C3≤0.1 μF”. ### Claim 15 (depends on 1) A motor comprising: a rotor which is rotatable with a center axis as a center; a stator comprising a three-phase coil; and the motor controller defined in claim 1. ### Claim 16 (depends on 15) A pump device comprising: the motor defined in claim 15; an impeller which is fixed to the rotor; and a case which accommodates the impeller and sections a pump chamber.