Motor controller

Patent metadata

Field	Value
Publication number	US-10673360-B2
Application number	US-201916273464-A
Country	US
Kind code	B2
Filing date	Feb 12, 2019
Priority date	Feb 19, 2018
Publication date	Jun 2, 2020
Grant date	Jun 2, 2020

Abstract

A motor controller includes a motor drive circuit, a noise cancellation circuit, and a control unit. The motor drive circuit supplies electric power to an electric motor. The noise cancellation circuit includes an RLC circuit, a switch element, and a pull-down resistor. One end of the RLC circuit is electrically connected to a positive terminal of a power supply via the switch element, and the other end of the RLC circuit is electrically connected to a frame ground. A connection point between the RLC circuit and the switch element is electrically connected to a negative terminal of the power supply via the pull-down resistor. The control unit turns ON the switch element for a predetermined time at falling timings of phase voltages output from the motor drive circuit.

First claim

What is claimed is:

1. A motor controller configured to control an electric motor having a housing connected to a frame ground to which a negative terminal of a power supply is connected, the motor controller comprising:
a drive circuit including series circuits of upper-stage switching elements and lower-stage switching elements connected in parallel to the power supply and provided for a plurality of phases, the drive circuit being configured to supply electric power to the electric motor;
a noise cancellation circuit; and
a control unit, wherein
the noise cancellation circuit includes an RLC circuit, a switch element, and a pull-down resistor, the RLC circuit being a series circuit of a resistor, a coil, and a capacitor,
one end of the RLC circuit is electrically connected to a positive terminal of the power supply via the switch element, and the other end of the RLC circuit is electrically connected to the frame ground,
a connection point between the RLC circuit and the switch element is electrically connected to the negative terminal of the power supply via the pull-down resistor, and
the control unit is configured to turn ON the switch element for a predetermined time at falling timings of phase voltages output from the drive circuit.

2. A motor controller configured to control an electric motor having a housing connected to a frame ground to which a negative terminal of a power supply is connected, the motor controller comprising:
a drive circuit including series circuits of upper-stage switching elements and lower-stage switching elements connected in parallel to the power supply and provided for a plurality of phases, the drive circuit being configured to supply electric power to the electric motor;
a noise cancellation circuit; and
a control unit, wherein
the noise cancellation circuit includes an RLC circuit, a switch element, and a pull-up resistor, the RLC circuit being a series circuit of a resistor, a coil, and a capacitor,
one end of the RLC circuit is electrically connected to the negative terminal of the power supply via the switch element, and the other end of the RLC circuit is connected to the frame ground,
a connection point between the RLC circuit and the switch element is electrically connected to a positive terminal of the power supply via the pull-up resistor, and
the control unit is configured to turn ON the switch element for a predetermined time at rising timings of phase voltages output from the drive circuit.

3. A motor controller configured to control an electric motor having a housing connected to a frame ground to which a negative terminal of a power supply is connected, the motor controller comprising:
a drive circuit including series circuits of upper-stage switching elements and lower-stage switching elements connected in parallel to the power supply and provided for a plurality of phases, the drive circuit being configured to supply electric power to the electric motor;
a first noise cancellation circuit;
a second noise cancellation circuit; and
a control unit, wherein
the first noise cancellation circuit includes a first RLC circuit, a first switch element, and a pull-down resistor, the first RLC circuit being a series circuit of a first resistor, a first coil, and a first capacitor,
one end of the first RLC circuit is electrically connected to a positive terminal of the power supply via the first switch element, and the other end of the first RLC circuit is electrically connected to the frame ground,
a connection point between the first RLC circuit and the first switch element is electrically connected to the negative terminal of the power supply via the pull-down resistor,
the second noise cancellation circuit includes a second RLC circuit, a second switch element, and a pull-up resistor, the second RLC circuit being a series circuit of a second resistor, a second coil, and a second capacitor,
one end of the second RLC circuit is electrically connected to the negative terminal of the power supply via the second switch element, and the other end of the second RLC circuit is connected to the frame ground,
a connection point between the second RLC circuit and the second switch element is electrically connected to the positive terminal of the power supply via the pull-up resistor, and
the control unit includes:
a unit configured to turn ON the first switch element for a predetermined time at falling timings of phase voltages output from the drive circuit; and
a unit configured to turn ON the second switch element for a predetermined time at rising timings of the phase voltages output from the drive circuit.

Assignees

• Jtekt Corp

Inventors

• Matsuhisa Koichiro
• Sumasu Hiroshi

Classifications

• H02M1/00

  Details of apparatus for conversion · CPC title

• H02M2001/123

  Electricity · mapped topic

• B62D5/0406

  including housing for electronic control unit · CPC title

• H02M7/5395

  by pulse-width modulation · CPC title

• H02K11/33

  Drive circuits, e.g. power electronics (H02K11/38 takes precedence) · CPC title