Design And Research Of Tomatoes Color Sorter High Speed Drive System Based On FPGA

Tomato color sorter can distinguish the green tomatoes and other impurities that mixedwith raw tomaes, and remove them effectively. Available tomato color sorter still existingthese problems, such as the high-speed solenoid valve driving system of eliminate mechanismhas a high heating and energy consumption, slow response, multiple simultaneously lowexecution efficiency, which can affect the sorting effect of tomato color sorter. Focus on theexisting problems on high-speed solenoid valve driving system in color sorter, in view of therequirements of low power consumption and high speed multiple processing and parallelimplementation, the dissertation analyzed the various types of driving modes of solenoidvalve, and designed a solenoid valve driving system of processing tomato color sorter basedon FPGA in the Modbus Protocol.Firstly, the dual voltage PWM driving mode was selected through the analysis ofdifferent kinds of solenoid valve driving modes at home and abroad, and selected the coreFPGA version of the drive system. At the same time under the comparative analysis onpresent popular communication network and protocol, chose the RS-485communicationnetwork and Modbus protocol for the actual working needs of solenoid valve driving andcomparative analysis.Secondly, by the use of modern EDA technology, the hardware circuit of high-speedsolenoid valve driving system was designed, moreover, DXP2004was utilized to theperipheral driving circuit(such as the clock circuit, reset circuit, power supply circuit) of coredevices FPGA. This paper chose the field effect transistor model of driving circuit, completedfunction simulation of driving circuit through Multisim10, besides, and devised thecommunication interface of driving system circuit based on Modbus communication protocolswith DXP2004. Drawn through the simulation, the solenoid valve shut dowm time shortenedby50%at high volt shutdown than low volt shutdown, thereby improving the response speedof the solenoid valve.Thirdly, after the analysis of Modbus protocol structure, the driving system program isdivided into the communication program and the PWM program two parts. Thecommunication program is made up of several modules, which are baud rate clock module,character receiving and sending module, frame reception and transmitting module, CRCmodule, data processing module, T35module, T15module, state machine by using moduledesign method. Quartus II is used to realize the design and functional simulation of eachmodule of communication program module, so does the design and timing simulation ofPWM program. Through timing simulation, Generated PWM drive waveform coincide withthe expected waveform, and generated waveform also meet the requirements of high-speedoperation of the hardware system of the electromagnetic valve driving system. By the way ofinstantiation, this article called the sub-module completed the design of top-level module; italso used the symbol files to complete the design of the software system. At the end, with Hi-tech man-machine interface as the master, make the verification ofcommunication function for driving system between master and the PWM waveform outputof driving system. All design achieved the desired goals, and come to the conclusion: Firstly,high-speed solenoid valve driving system can realize the effective communication with themaster, received the PC read and writes orders of the action parameters. Secondly, solenoidvalue driving system can produce the high volt to open, low volt PWM waveform to maintain,and enhanced50percent of the action frequency. Thirdly, newly designed solenoid valuedriving system solved the original solenoid valve problem of high heating.