Design And Implementation Of IP Core For Servo Control Dedicated SoC

Modern industrial automation has produced higher requirements for motor servo,including position accuracy,dynamic response,electromagnetic compatibility and so on.At the same time,industrial Ethernet has also appeared along with industrial automation’s requirements for real-time and data bandwidth.The main purpose of this subject is to design and develop a dedicated SoC and supporting IP core for industrial servo control to meet the needs of modern industrial control for high dynamic response and real-time communication control.In order to meet the requirements of motor servo for high dynamic response,we have developed a current loop control hardware accelerator in the SoC to reduce the operation delay in the current loop.In the subject,the research and products of the previous hardware current loop controllers are analyzed,and it is believed that the previous hardware structure has problems such as poor flexibility,waste of resources,and complex control logic.The subject innovatively proposed the use of dataflow computing architecture for hardware acceleration of current loop control.The dataflow computing architecture is data-driven,shared execution units,inherently powerful in parallelism,and programmable.So as to solve the shortcomings in previous research.In the subject,the corresponding assembler and instruction scheduler were designed for the dataflow processor,and the programming model was shown.Motion control engineers can currently build their own current loop control algorithm hardware accelerators through assembly language.In order to satisfy the servo controller’s attention to high-bandwidth real-time communication,we have added a slave controller compatible with the EtherCAT data link layer specification in the SoC.According to the description of the EtherCAT protocol,the slave controller is divided into three layers for implementation: physical interface layer,data frame real-time processing layer and bus interface layer.The corresponding driver software can run in frame synchronization mode and free mode,providing mailbox data communication and process data communication services.Finally,the entire servo control SoC was designed on the zynq-7000 device,and the servo control hardware platform was built.The current loop control test was completed on the experimental platform,and the test results showed that the current closed-loop tracking gain was-0.28 d B at 1KHz,and the phase lag was 40.8°.The bandwidth of current closed-loop tracking is between 2KHz and 4KHz.EtherCAT can transmit current commands and feedback in real time.The servo control SoC designed in this paper has a programmable current loop controller,which can adapt to different current loop control algorithms.The EtherCAT slave controller is integrated on the chip,which can support EtherCAT communication without an external chip.The current loop controller designed for permanent magnet synchronous motors can reach a current loop bandwidth of 2 to 4KHz.