Christian Vocke Supercritical Boiler Control & Operational Experience

Since August 2002 RWE Power operates the most advanced lignite-fired unit of the 1000 MW class at NiederauBem power station. With a supercritical live steam condition of 275 bar and 580°C and a reheat temperature of 600°C the highest steam parameters ever built for utility boilers in Europe were realised. The highlight of the control system is the consequent use of field bus technology for the actuators keeping the existing I&C standards and focusing on the issue of redundancy. The possible difficulties, discussed in front of the decision to use field bus, didn´t occur during operation up to now. Problems which arose in the commissioning phase caused by the field bus actuators itself could be eliminated and gave good new ideas for the next projects. Some of the theoretical added values of field bus actuators can´t be used today in daily maintenance.