Control System Design For Hydrogen Production Plant By Water Electrolysis Of Hydrogen Fueling Station

With continuous development of our nation economy, the autocar market has been increasingly growing up, the pollution to atmosphere caused by exhaust gas from autocar take a much serious effect on the standing continuable development, it results the development of hydrogen energy is being emphasized by all the world. At present, the technology of fuel cell is regarded as the developing direction to the autocar industry by all the nation. However, with the marketing of fuel-cell autocar, the filling technology of auto car fuel is becoming more and more imperative, therefore, the it is very important and necessary for infrastructure of hydrogen filling station such as the hydrogen generator to be researched and developed.PLC control logic design, safety design and principle design of automatic control system have been completed in this article for hydrogen generator by water electrolysis which is typically used for hydrogen fueling station.(1) The principle design of automatic control system. Special measures have been designed for operating pressure, levels and operating temperature which effect on the running of hydrogen generator and the control accuracy and operating reliability have been rapidly improved via setting of suitable control points and modeling of PLC; all necessary auxiliary facilities has been configured to decrease the request by the generator to outside and operating cost.(2) Safety design of automatic control system. Aiming at safeyt requirements for hydrogen fueling station, safety design includes alarm loop, soft-interlock loop and hard-interlock loop, etc. and the corresponding set-point values are designed as per the ascending sequence for alarm, soft-interlock and hard-interlock. Inside of these design, the hard-interlock can perform the protection of hydrogen generator from PLC malfunction, which can improve greatly the safety of operation.(3) PLC control logic design. Aiming at the requirements by communication between PLC and computer to control system, the PLC control logic is divided into three portions, main program, sub-program and function modules, etc. In the programming, all sorts of function modules have been designed in order to structure automatic control system in conformity with requirements and conveniently to maintain the control logic.Design of hydrogen generator is integrated and combined in one containerized housing to shorten the volume of generator and decrease the difficulty in erection on site. PLC is applicable in control system to improve the control accuracy and automation. In safety design, hard-interlock has been introduced to protect generator from the PLC malfunction; these designs shorten the volume of integrated generator, decrease the requirements to the environment, lower the operation cost and improve greatly the safety and reliability of operation of generator.