The Design Of Distributed Control System In Medium And Small Scale Power Plant

In the industrial process control field, there are three dominating control systems, namely distributed control system (DCS),programmable controller (PLC), field bus control system (FCS). Each of the three systems has its own feature and predominance. But the FCS is not mature in using till up to now, and the predominance of PLC is disposing digital quantity, so it's mainly used in the sequential control among the industrial control production. The DCS is widely used by contract, and it has the ability to dispose analog quantity conveniently.Aiming at the object feature and the function demand of the domestic medium and small scale power plant, in this paper we design and develop the DCS suitable to the operation and monitor demand of the medium and small scale power plant. It includes field I/O control station (field I/O control master station, field I/O control substation), engineer station, operator station.The work in this paper is developing and designing the software and hardware of the DCS including it's field I/O control station (field I/O control master station, field I/O control substation), engineer station, operator station. By developing the iFix I/O driver and the configuration picture which running on the engineer station and operator station., this paper well solved the problem such as bad architecture and extensibility among the other special DCS in medium and small scale power plant; By designing the software of data acquisition and control system (DPU routine) which running on the field I/O control master station, this paper well improved the problem such as low ratio of using auto control loop of the DCS. By applying the EF measure control module as the field I/O control substation, this paper gave a good distribution characteristic comparing to the other special DCS in medium and small scale power plant.Based on the object feature of the small and medium domestic power plant and combined with the trend of heat engineering automation, the author of this paper has worked out the special DCS which is reliable, economical and with good overall performance; also the special DCS has been applied on the industrial working site and has gained good economical benefit.