Servo system and control method for servo system

Patent metadata

Field	Value
Publication number	US-12519415-B2
Application number	US-202218564632-A
Country	US
Kind code	B2
Filing date	Jun 10, 2022
Priority date	Aug 3, 2021
Publication date	Jan 6, 2026
Grant date	Jan 6, 2026

Abstract

The servo system includes a servo motor, an encoder for detecting rotation information regarding the position and speed of the servo motor, and a servo amplifier for controlling the driving of the servo motor using the rotation information. The servo amplifier includes an encoder communication interface configured by hardware, a processor for calculating a control command to control the servo motor based on an operation command and the rotation information input through the encoder communication interface, and a control unit for controlling the driving of the servo motor based on the control command. Then, the processor compares the rotation information directly received from the encoder with the rotation information input through the encoder communication interface and diagnoses that there is a failure when both the pieces of rotation information do not match each other.

First claim

The invention claimed is:

1 . A servo system, comprising:
a servo motor; an encoder that detects rotation information of the servo motor; and a servo amplifier that controls driving of the servo motor using the rotation information, wherein the servo amplifier includes an encoder communication interface configured by hardware, a processor for calculating a control command to control the servo motor based on an operation command and the rotation information input through the encoder communication interface, and a control unit for controlling driving of the servo motor based on the control command, wherein the processor compares the rotation information directly received from the encoder with the rotation information input through the encoder communication interface and diagnoses whether or not there is a failure in the encoder communication interface based on a result of the comparison between both the pieces of rotation information, and wherein a serial communication interface that receives and stores the serial rotation information transmitted from the encoder and transmits the stored data in FIFO order to the processor and the encoder communication interface is provided.

2 . The servo system according to claim 1 ,
wherein a microcontroller unit is used as the processor.

3 . The servo system according to claim 1 ,
wherein a request generation unit that generates a request for determining data to be received of the rotation information is provided in the processor, and the request is transmitted to the encoder through the serial communication interface so that the encoder transmits the rotation information corresponding to the request to the serial communication interface.

4 . The servo system according to claim 1 ,
wherein the serial communication interface is provided at an input end of the processor.

5 . The servo system according to claim 1 ,
wherein information obtained by thinning out the rotation information input through the encoder communication interface is compared with the rotation information directly received from the encoder.

6 . The servo system according to claim 1 ,
wherein when the failure is diagnosed, emergency measures are taken for the servo system.

7 . The servo system according to claim 1 ,
wherein the processor includes input/output pins corresponding to functions of a dynamically reconfigurable processor and a serial communication interface, and the serial rotation information transmitted from the encoder is received by the input/output pins.

8 . A servo system comprising:
a servo motor; an encoder that detects rotation information of the servo motor; and a servo amplifier that controls driving of the servo motor using the rotation information, wherein the servo amplifier includes an encoder communication interface configured by hardware, a processor for calculating a control command to control the servo motor based on an operation command and the rotation information input through the encoder communication interface, and a control unit for controlling driving of the servo motor based on the control command, wherein the processor compares the rotation information directly received from the encoder with the rotation information input through the encoder communication interface and diagnoses whether or not there is a failure in the encoder communication interface based on a result of the comparison between both the pieces of rotation information, wherein the encoder communication interface is built into the processor, wherein a dynamically reconfigurable processor is used as the encoder communication interface, and wherein a serial communication interface that receives and stores the serial rotation information transmitted from the encoder and transmits the stored data in FIFO order to the processor and the encoder communication interface is built into the processor.

9 . A control method for a servo system that includes a servo motor and an encoder for detecting rotation information of the servo motor and drives the servo motor based on the rotation information of the encoder, the method comprising:
driving the servo motor based on an operation command and the rotation information input through an encoder communication interface using hardware; comparing the rotation information input through the encoder communication interface and the rotation information directly input from the encoder; and diagnosing whether or not there is a failure in the encoder communication interface based on a result of the comparison between both the pieces of rotation information, wherein the rotation information is imported into the encoder communication interface through a serial communication interface that receives and stores the serial rotation information transmitted from the encoder and transmits the stored data in FIFO order.

10 . The control method for a servo system according to claim 9 ,
wherein a request for determining data to be received from the encoder is generated, the request is transmitted to the encoder, and the rotation information corresponding to the request is input from the encoder.

11 . The control method for a servo system according to claim 9 ,
wherein information obtained by thinning out the rotation information input through the encoder communication interface is compared with the rotation information directly received from the encoder.

12 . The control method for a servo system according to claim 9 ,
wherein the failure is diagnosed, emergency measures are taken for the servo system.

Assignees

• Hitachi Industry Equipment Systems Co Ltd

Inventors

• Luo Zhiyuan
• Ikeda Takahiro
• Iimuro Satoshi
• Takeda Kenji

Classifications

• G05B2219/33329

  Measuring system, encoder · CPC title

• G05B19/4063

  Monitoring general control system (G05B19/4062 takes precedence) · CPC title

• H02P29/024 Primary

  Detecting a fault condition, e.g. short circuit, locked rotor, open circuit or loss of load · CPC title