Design And Implementation Of Data Acquisition And Signal Processing For High Power Supply Based On FPGA

High power millimeter wave gyrotron traveling wave tube(Gyro-TWT)can play an important role in military,aviation,national defense and other important fields because of its high output power,wide working band and high efficiency.In order to make gyrotron traveling wave tube work stably in test and application,a stable high-power power power supply system is needed to supply energy for it.Therefore,it is necessary to grasp and monitor the key signals in the power system.According to this demand,this paper designs a set of data acquisition and signal processing system of high-power power supply based on FPGA,aiming at the deficiency of PLC in data acquisition and signal processing function of existing industrial controller of high-power power supply system,so as to realize the acquisition and processing of key signal in power supply system and sparking signal of Gyro-TWT.According to this functional requirement,this paper analyzes the performance index that the system should meet,selects the key chips needed to realize the system,and then puts forward the overall design idea and framework.The whole system is developed based on Verilog hardware programming language,using the top-down digital system design method,and processing and verification of data with MATLAB.The system is divided into three parts: data acquisition,digital signal processing and serial communication.For the data acquisition part,it is responsible for receiving the analog-to-digital converted data sent from the peripheral high-speed AD sampling chip,and storing it in DDR3 memory in time.The storage mode is customizable cyclic storage,which can effectively use the storage space of DDR3.Further more,In this part,a precise trigger control module is designed,which can choose and upload the key signals accurately through the hybrid trigger mechanism of edge trigger and pulse width trigger,so as to improve the accuracy of data acquisition.For the part of digital signal processing,it is responsible for the digital filtering processing of the signal collected by the system which is subject to external electromagnetic interference.Two kinds of digital filters are designed to accomplish the work of digital filter together: FIR filter and smoothing filter,which are widely used.And the traditional structure and algorithm of these two filters are improved,so that the filter can greatly reduce the operation error and is more suitable for signal processing in high-power power system,and the cascaded structure of the two filters is given.Compared with the use of a single filter,it can improve the overall filtering effect without increasing the order.For the serial communication part,it is used to complete the communication between the host computer and the system,so that the system can receive the instructions sent by the host computer through the serial port,and upload the collected and processed data to the host computer.The most widely used field bus communication protocol: Modbus communication protocol is adopted as the communication protocol.Through this protocol,the system can be integrated into the existing Modbus communication network of high-power power supply to realize the convenience and standardization of communication.Finally,the data acquisition and signal processing system is converted into bitstream file and downloaded to FPGA chip,and the hardware is debugged and verified by the development board.Several key signals in the high-power power supply system and the sparking signal of Gyro-TWT are collected and processed,and the correctness of the designed system is verified by the test results.Through the data acquisition and signal processing system of high-power power supply based on FPGA designed by this paper,the key signals of high-power supply system and the sparking signal of Gyro-TWT are captured and monitored.The design can effectively make up for the defects of PLC in data acquisition and signal processing.Compared with the method of directly grasping and observing the signal with oscilloscope,the design has the advantages of high portability,expansibility,low power consumption and low cost.The design of the high voltage pulse modulation powersupply is significiant for the good performance of Gyro-TWT.