Motor controller, motor and pump device

Patent metadata

Field	Value
Publication number	US-12015312-B2
Application number	US-202217692213-A
Country	US
Kind code	B2
Filing date	Mar 11, 2022
Priority date	Mar 16, 2021
Publication date	Jun 18, 2024
Grant date	Jun 18, 2024

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.

First claim

What is claimed is:

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.

2. The motor controller according to claim 1 , wherein when a capacitance of each of the second capacitor and the third capacitor is defined as C 1 , the C 1 satisfies a following conditional expression:
“0.047 μF≤ C 1≤0.33 μF”.

3. 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.

4. 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.

5. The motor controller according to claim 4 , wherein when a capacitance of the first capacitor is defined as C 2 , the C 2 satisfies a following conditional expression:
“100 μF≤ C 2”.

6. 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.

7. 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.

8. 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.

9. The motor controller according to claim 8 , wherein when a capacitance of the fifth capacitor is defined as C 3 , the C 3 satisfies a following conditional expression:
“ C 3≤0.1 μF”.

10. The motor controller according to claim 1 , wherein when a capacitance of the first capacitor is defined as C 2 , the C 2 satisfies a following conditional expression:
“100 μF≤ C 2”.

11. 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.

12. 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.

13. 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.

14. The motor controller according to claim 13 , wherein when a capacitance of the fifth capacitor is defined as C 3 , the C 3 satisfies a following conditional expression:
“ C 3≤0.1 μF”.

15. 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 .

16. 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.

Assignees

• Nidec Sankyo Corp

Inventors

• Tanimura Satoshi
• Yamamoto Takashi

Classifications

• H02P1/44

  by phase-splitting with a capacitor · CPC title

• F04D25/06

  the pump being electrically driven (F04D25/08 takes precedence) · CPC title

• F04D29/40

  Casings; Connections of working fluid {(bleed or by-pass valves F04D15/0011, F04D27/0215)} · CPC title

• F04D29/669

  especially adapted for liquid pumps (F04D29/18 takes precedence) · CPC title

• F04D13/06

  the pump being electrically driven · CPC title