The Design And Research Of BST-6 Seeder Test-bed Frequency Conversion And Control Speed System

For BST-6 seeder test-bed,in order to realize adjusting test parameters conveniently,we designed the variable frequency speed regulation system based on PLC logic control modle to improve the automatic degree of test process.The system is able to meet numerous demands such as beltl ineal speed,wheel speed,seed plate speed,real-time regulation of flow of fan,transfering seeder from clamping position to test position and other test critical procedures.Mainly work in Hardware part:(1)The bearing seed belt drive motor, wheel drive motor, fan drive motor,lifting motor and rotary motor of lifting slide,respectively,are calculated of those parameters related to the rated speed, rated power, rated torque.(2)I/O port points estimation, output mode selection, D/A special module parameters design and calibration of special module input current are carried out on the programmable logic controller.(3)The design of the relevant parameters of low-voltage electrical equipments, such as rated voltage, rated current, short circuit current, and calculate the relevent parameters of encoder.(4)The capacity, current and load capacity of frequency converter is carried out, and the relevant parameters such as maximum operating frequency, motor rated frequency, motor rated voltage and other related parameters are set.Mainly work in Software part:(1)Programming for automatic control procedures, back to the origin of the procedure, manual procedure.(2)By using VC++ software, the main interface of the control system of BST-6 seeding machine, the manual operation interface, fan’s parameters setting interface.(3)Using GX-Simulator to simulates logic control ladder program about automatic control program, back to the origin program and manual program.The results shows that the speed adjustable range of the belt driving motor is 0～1437.9r/min, and the speed error is within 0.1r/min, which can make the speed of the belt line speed between 0～3km/h;wheel diameter range of 0.5～1.2 m with a precision of 0.1, the wheel frequency between 0～57.33Hz, the land wheel drive motor speed range can be adjusted in 0～589.9r/min, it is able to adapt to different sowing speed requirements;fan motor speed range of 0～3000r/min, can be adapted to the flow range in the 0～50 range of fans;the height of the seeding machine is adjusted by varing the of the electric power time of the elevator, the height range from 0 to 500mm.In summary, the development of variable frequency speed regulation system which is on the BST-6 seeder test-bed realizes the parameter setting and adjustment of intelligent control, which can make the whole testing process efficient and convenient for research of agriculture machine,it also provides reference to other agricultural machinery test automation equipment.