Study of two-cell immune feedback control for water level of boiler drum based on gray prediction
Due to the ‘false water level’ phenomenon in power station makes the traditional control strategy can't be a good solution to the problem, a two-cell immune feedback control strategy based on gray prediction for water level of boiler drum in power station is proposed, which using the function of gray prediction with strong self-adaptability and advanced control functions, and learning from bio-feedback mechanism of the immune system and regulating rule of response process. Through lots of simulation studies, it can achieve a more satisfied control quality with strong robustness and anti-jamming capability. Meanwhile, the structure and algorithm of the control strategy are simple and easy to engineering implementation.
Application of grey self-tuning fuzzy immune PID control for main steam temperature control system
The prominent virtues of grey prediction are small information, few data and a little of computation. The conventional PID controller has strong robustness, sophisticated technology and simple structure, so it has been used widely in the process control. With the adjustable role of feedback response of biological immune systems, the capability of simulating non-linear functions with fuzzy rationalizing logic, and the advantage of gray prediction, an application of fuzzy immune PID control with gray prediction has been proposed. In view of the grey-step having great effect to the results of forecast, the fuzzy rules are used to adjust the forecast step, which is a very good supplement to the grey prediction. The method mentioned in this paper is applied to the main steam temperature control system of power plant, the simulation shows that this strategy has strong capability of anti-disturbance.
Recalculation of Mass Defects
THE well-known mass defect curve of the old nuclear scheme calculated with regard to α-particles and protons presented a difficulty with its minimum of binding energy for tin and an increasing portion between tin and lead. On the other hand, the mass defect values against protons give a rather smoothly decreasing curve.1 As has already been pointed out,2 the number of α-particles must be considerably reduced from the point of view of the new scheme, which does not admit any electrons in nuclei, but only neutrons and protons (presumably joined as α-particles). The curve of mass defect against protons and neutrons (perhaps with a single ‘central’ α-particle) is very similar to the old curve against protons, but decreases less rapidly. Clearly the new mass defect values relatively to α-particles, neutrons and protons must lie somewhere between the old values computed relative to protons and α-particles respectively (because the number of α-particles is decreased). We may emphasise that this new mass defect curve shows no increasing portion between tin and lead. For illustration we give two typical values: Old: 50Sn124 = 31α + 12&#38;epsiv;; mass defect = 0.158 (in mass units); 82Pb208 = 52α + 22&#38;epsiv;; mass defect = 0.035. New: 50Sn124= 25α + 24ω (ω = neutron); mass defect = 0.304; 82Pb208 = 41α + 44ω; mass defect = 0.366.