Research On Safety EPLC Based On FPGA

Along with the centralization and large scale of modern industrial production,industrial accident more and more to the life, property and environmental damagecaused by the greater, while the market demand for the safety control system isincreasing as the result. A design of a safety controller model which is based on loo2Dsystem structure is proposed. By using the FPGA technology and BLVDS technology,the model completed the necessary safety features, without additional MCU resourcesconsumption. This paper mainly completes the following works:1) Through the safety controller system structure research in IEC61508standard, asafety controller model based on loo2D structure is designed, which is divided intoredundant power supply module, main control module, safety input/output moduleand backplane module.2) Integrating the open ePLC technology and FPGA technology to achieve the maincontrol module function, designing the structure diagrams of each module, andproviding the hardware implementation of key circuit of the function modules.3) A complete set of reliable communication mechanism between modules, whichbased on FPGA technology and BLVDS technology is designed, that realized the datainteraction of FPGA with redundant module and safety module of I/O. Completed thesynchronization and diagnosis between the main redundant control module, bymodifying the ePLC engine, introduced additional Synchronization function.4) The fast response and high reliability of the communication mechanism FPGAtechnology and BLVDS technology were validated experimentally. Analyzed thesafety mechanisms by using FTA. Evaluated the safety level of the system, byreferring to the GJB/Z299C the expected reliability of Electronic EquipmentHandbook, SINTEF database, and According to the standards of safety integrity levelin IEC61508.This paper made some attempts and explorations on safety PLC based on loo2Dstructure, which would have a good prospect and needs to be validated in practice.