Design Of Drive And Control System For Digital Agriculture Platform

Drive and control system is the power source of the precise producing technology platform about digital agriculture. It includes the realization of the basic motion control. The quality of the drive and control system influences directly the feasibility and precision of the whole platform. The drive system need to be controlled by programs and not only offers enough energy to the platform, but also need have the high control precision.Taking into account the actual requirements of the plattform, the paper analysed several kinds of drive motors and drive technology used in electric vehicles and chose GLMI15A1(for the electric vehicle specially) to serve the platform as the drive motor, Programmable Logic Controller (PLC-FX2N) as the kernel controller, Iintelligent Power Module (IPM-PM300CVA060) as the power convertor.At first, the paper did the theoretic analyse and study on the technology of vector control to asynchronous motors, and decided to take RFOC (Rotor Field Oriented Control) technology to accomplish the undo-coupling control between the excitation current and torque current. Like that, the paper offered the principle chart of the vector control. Because the performance of vector control is restricted by the time constant of the rotor, the paper brought forward a method to test the time constant of asynchronous motors. The paper also offered a way to measure the excitation share and the torque share of the stator current in engineering practice.The tecnology of energy feedback plays an immportant role in the electric drive system, so the paper brought forward a project to carry out the energy feedback. It is that we can get the feedback energy through changing the direction of torque current under the condition of the changeless excitation. The feedback current is determined by the characteristics of cells'charge and discharge.The paper presented the design of hardware and software for the drive control system. It included storage batteries, motors, controllers, IPM and high speed counter (HSC) modules, arithmetic of vector control by PLC,etc.Thinking of the actual application, the paper showed some questions and steps on several interrelated equipments.