CN-121984392-A - Current control device, current control method and servo system of servo driver

Abstract

The embodiment of the application provides a current control device, a current control method and a servo system of a servo driver. The current control device comprises a prediction module and a sector judgment module, wherein the prediction module generates an output voltage at a fourth moment in a second carrier period according to the output voltage at a first moment in the first carrier period and the output voltage at a second moment in the second carrier period after the first carrier period, and the sector judgment module determines a target sector according to the output voltage at the third moment and the output voltage at the fourth moment if the output voltage at the third moment and the output voltage at the fourth moment belong to different sectors, so that the sector judgment accuracy is improved, and the problem of pulse width modulation signal error caused by sector errors is avoided.

Inventors

• NIU YUXIANG
• GUO XIANJIE
• GUAN PENG

Assignees

• 欧姆龙(上海)有限公司

Dates

Publication Date

20260505

Application Date

20260130

Claims (10)

1. 1. A current control device of a servo driver, characterized in that the current control device comprises: a prediction module for generating an output voltage at a fourth time in a second carrier period after a first carrier period based on an output voltage at a first time and an output voltage at a second time in the first carrier period and an output voltage at a third time in the second carrier period after the first carrier period, and And the sector judgment module is used for determining a target sector according to the output voltage at the third moment and the output voltage at the fourth moment so as to be used for pulse width modulation if the output voltage at the third moment and the output voltage at the fourth moment belong to different sectors.
2. 2. The current control device according to claim 1, wherein, The sector judgment module determines a target sector, comprising: And selecting a sector corresponding to a larger value in the weights of the sectors to which the output voltage at the third moment belongs and the sectors to which the output voltage at the fourth moment belongs as the target sector.
3. 3. The current control device according to claim 2, wherein, Calculating the difference value of the amplitude and the direction of the output voltage at the third time and the output voltage at the fourth time, and And calculating the weight of the sector to which the output voltage at the third moment belongs according to the amplitude value difference and the direction difference.
4. 4. The current control device according to claim 2, wherein, And calculating the weight of the sector to which the output voltage at the fourth moment belongs according to the weight of the sector to which the output voltage at the third moment belongs.
5. 5. The current control device according to claim 1, wherein, The sector judgment module further includes: Calculating a reference vector angle at a third moment according to the output voltage at the third moment, and calculating a reference vector angle at a fourth moment according to the output voltage at the fourth moment; calculating a sector to which the output voltage at the third moment belongs according to the reference vector angle at the third moment, and calculating a sector to which the output voltage at the fourth moment belongs according to the reference vector angle at the fourth moment, and And judging whether the output voltage at the third moment and the output voltage at the fourth moment belong to the same sector.
6. 6. The current control device according to claim 1, wherein, The prediction module generates an output voltage at a fourth time, comprising: and constructing a second-order polynomial extrapolation model according to the output voltage at the first moment, the output voltage at the second moment and the output voltage at the third moment, wherein the second-order polynomial extrapolation model outputs the output voltage at the fourth moment.
7. 7. The current control device according to claim 1, characterized in that the current control device further comprises: and the processing module is used for generating an output voltage at the first moment, an output voltage at the second moment and an output voltage at the third moment according to the current sampling values at the first moment and the second moment in the first carrier period and the third moment in the second carrier period.
8. 8. The current control device according to claim 7, characterized in that the current control device further comprises: and the modulation module is used for judging whether the sector to which the output voltage at the fifth moment in the third carrier period after the second carrier period belongs is separated from the target sector by more than one sector or not.
9. 9. A servo system, the servo system comprising: A servo driver comprising a current control device as claimed in any one of claims 1to 8, and A servo motor is arranged on the upper surface of the shell, The servo driver generates a pulse width modulated current according to a target sector to drive the servo motor.
10. 10. A current control method of a servo driver, the current control method comprising: Generating an output voltage at a fourth time in a second carrier cycle from an output voltage at a first time and an output voltage at a second time in the first carrier cycle and an output voltage at a third time in the second carrier cycle after the first carrier cycle, and And if the output voltage at the third moment and the output voltage at the fourth moment belong to different sectors, the sector judgment module determines a target sector according to the output voltage at the third moment and the output voltage at the fourth moment so as to be used for pulse width modulation.

Description

Current control device, current control method and servo system of servo driver Technical Field The embodiment of the application relates to the technical field of industrial automation, in particular to a current control device, a current control method and a servo system of a servo driver. Background The servo system is an execution unit for precise motion control in the field of industrial automation, and forms a complete closed-loop control system through a servo controller, a servo driver, a servo motor, a feedback device and other components. The servo driver is used as a core unit for system control and power conversion, a closed-loop control algorithm is built in, the closed-loop control algorithm comprises a cooperative working mechanism of a position loop, a speed loop and a current loop, and the servo motor is driven to realize position, speed or torque regulation. The feedback device acquires the actual motion state of the system in real time. In order to improve the performance of a servo system, a servo driver introduces a current loop control technology represented by double sampling and double updating, and is suitable for the scenes such as a permanent magnet synchronous motor and the like. In the double-sampling double-updating current loop control method, the current real-time sampling-control algorithm operation-PWM duty ratio updating cycle is completed twice in a single pulse width modulation (PWM, pulse Width Modulation) carrier period, so that the control delay is shortened, and the tracking speed and the anti-interference capability of a servo system on a current instruction are improved. It should be noted that the foregoing description of the background art is only for the purpose of providing a clear and complete description of the technical solution of the present application and is presented for the convenience of understanding by those skilled in the art. Disclosure of Invention The inventor finds that in the existing double-sampling double-updating current loop control scheme, for two current samples in the same PWM carrier period, only a Sector (Sector) of an output voltage vector corresponding to a first sampling time is generally calculated, and is used in pulse width modulation at a second sampling time, and for the case that output voltages corresponding to two sampling times belong to different sectors, the first Sector result is used for performing second pulse width modulation to cause PWM signal errors. Therefore, how to improve the accuracy of sector judgment under the double sampling and double updating mechanism is a problem to be solved. In order to solve at least one of the above technical problems or similar technical problems, an embodiment of the present application provides a current control device, a current control method, and a servo system of a servo driver. The current control device generates the output voltage at the fourth moment in the second carrier period, and determines the target sector according to the output voltages at the third moment and the fourth moment in the second carrier period for pulse width modulation. According to an aspect of an embodiment of the present application, there is provided a current control apparatus of a servo driver, including: a prediction module for generating an output voltage at a fourth time in a second carrier period after a first carrier period based on an output voltage at a first time and an output voltage at a second time in the first carrier period and an output voltage at a third time in the second carrier period after the first carrier period, and And the sector judgment module is used for determining a target sector according to the output voltage at the third moment and the output voltage at the fourth moment so as to be used for pulse width modulation if the output voltage at the third moment and the output voltage at the fourth moment belong to different sectors. In some embodiments, the sector determination module determines the target sector, comprising: And selecting a sector corresponding to a larger value in the weights of the sectors to which the output voltage at the third moment belongs and the sectors to which the output voltage at the fourth moment belongs as the target sector. In some embodiments, the magnitude and direction differences of the output voltage at the third time and the output voltage at the fourth time are calculated, and And calculating the weight of the sector to which the output voltage at the third moment belongs according to the amplitude value difference and the direction difference. In some embodiments, the weight of the sector to which the output voltage at the fourth time belongs is calculated according to the weight of the sector to which the output voltage at the third time belongs. In some embodiments, the sector determining module further comprises: Calculating a reference vector angle at a third moment according to the output voltage at the third moment, and c