| With the development of semiconductor and computer software technology, more and more cable hoist control system added the intelligent control. It has changed the traditional relay control mode. The first generation of intelligent control system adopts centralized control, it exists some problems, such as requiring more wire, complicated structure, and poor reliability. The introduction of field bus has solved these problems. It put the more data in the bus forcibly with special format, decreases the number of wries greatly, and improves the reliability of system. In the domestic, Modbus is the most extensive field bus protocol in using now. With the increasing complexity of systems, the data in bus become more, the way of single master become the biggest bottleneck in Modbus, at the same time greatly reduce the system real time, especially for double-cylinder synchronous system of deviation rectification and some protection module which require high real time, because system don’t get effective data timely, which led to the protection failure, there is a certain security risk.This paper is to use the new field bus protocol CANopen to build a programmble computer controller (PCC) experimental platform of cable hoist system of sluice with high real time, high efficiency, high flexibility, it can realize the quickly acquisition of all kinds of data in network, to prepare for the study of the dynamic process of sluice, to provide condition for all kinds of control algorithm simulation, to lay the foundation for application in actual product. Experimental platform is composed of master control module, pressure signal acquisition module, Angle encoder and signal conversion module, power acquisition module, temperature acquisition module, USB communication module, man-machine interface and other components, experimental platform to master control module as the center, joines all the data acquisition module with the CAN bus. Master control module obtain the data of acquisition module through the CANopen network in real time and merge it, finally, to upload it the computer, and display on man-machine interface in real time. Master control module control the operation of the sluice through receiving computer commands or getting local switch’s state, and judge the state of sluice through obtaining acquisition module’s data, if an exception occurs,Master control module immediately terminate operation of the sluice. The computer through USB communication module connected to the CANopen network, get sluice’s state date from main control module, using to real-time display and save.CAN bus is a kind of high reliability and high performance of field bus which developed by Bosh, it is widely used in automotive and industrial applications. CAN is only the data link layer protocol, this limited its development, so application layer protocol CANopen which was base on CAN was developed by CIA. This paper analyzed the CANopen protocol, and realized the function of the protocol in STM32F10X, and used it in the each module of experimental platform. This paper completed the hardware and software design of each module of the experimental platform, these modules contain master control module, pressure signal acquisition module, angle encoder signal conversion module, power acquisition module, temperature acquisition module, the USB communication module, realized the operation of combined network. Experiment results proved that response speed of the experimental platform base on CANopen rose from about IS to100mS, relative to the experimental platform base on Modbus. These modules not only for this experiment platform, and also applies to other systems.This paper supported by Major Science and Technology Planning Project "study of non-contact load sensor" of Panlong District, Kunming City.(Contract No. PKX (2011)12)... |
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