Research On Multi-scale Energy Consumption Characterization And Control Law For Power Plant Cool-end

Cool-ends of the power plants are essentially complicated systems with many equipment and many processes. To decrease their energy consumption and to obtain the optimal control stratege is always concerned by thermal power plant energy-saving pursuer. At the same time, it is also pivotal and difficult part for deeply sinking energy-saving potential so as to realize the aim. Hence, to study on pivotal question and to put forward resoluble project has great significance for more improving the cool-end system economic. The project has theory connotation and currency characteristic with a certain extent. Three pivotal parts for energy-saving is proposed in the paper i.e. optimum design of the most energy consumption equipments in the cool-end system, optimization selecting type, system optimizing regulation. It is difficult to abstract energy consumption hypostasis from existing theory so as to provide theory support for solving energy consumption pivotal parts. Three part is independent, suspensory and probative one another. The main contributions of the paper are as follows:1. According to turbomachinery flow theory, loss mechanism has been analyzed for the secondary flow, vortex, return inside the impeller. Pointed out the inadequacy of traditional theory is mainly manifested in two aspects. The first is its object mainly for axial. The second is too much emphasis on appearance analysis, neglect to explore the mechanical nature. On this basis, from the point of vortex dynamics theory, some qualitative relations associated with the secondary flow losses is obtained.2. The critical impact parameter to affect the formation of secondary flow has been found. If it is as free parameters to optimize, an optimal design new method based on secondary flow control for blade can be obtained. As demonstrated by examples, this method can effectively reduce or eliminate the impact of secondary flow and improve efficiency.3. Its ability to adapt to the speed regulation has been analyzed from the efficiency curve characteristics and changing law for mixed flow pump.At the same time, rational and scientific features can be found for circulating pump with two-speed motor adjustment from mixed flow pump load characteristics and the load rate on the two-speed motor efficiency law.4. For the cold side of condenser vacuum on the unit performance, and the features by adjusting the number of circulating water pump, the new concept of minimal matching water quantity has been put forward. It can serve as a guide for optimal regulation. During the research of control the deviation level by circulating water pump actual water quantity to minimal matching water quantity, multiple-speed chiasma and parallel connection theory has been proposed. The optimization alteration project was developed by it.5. Considering the impact by various reform programs to circulating pump circulating water flow, a slight increase of turbine power, power consumption of circulating pump, alteration will be based on the best vacuum equipment optimization as the optimization target, and objective function has been established to a circulating water system. Finally, as a cold end optimization of transformation shown, verifying the theory of multi-speed cross-parallel scientific and effective.