Research On Rapid Load Control Of Coal-fired Power Plants Basced On Condensate Throttling

Improving the rapid response ability for coal fired power plants is an effective way to solve the fluctuation causing by large-scale renewable energy integration in grid,which is the necessary way to insure security and stability for grid.Although the integration of renewable sources is increasing rapidly in the past decade,the coal fired power plants are still make up a relatively significant share in integration(57.3%)and output megawatt(65.2%),which reveal that coal fired power plants is still the primary sources in electric power generating system.Thus,enhancing the ability rapid response ability for coal fired power plants is the feasible choice in the coursing of developing renewable sources.The coordinate control system(CCS)is commonly used in traditional power output regulation in power units,the control system had applied the stored energy in boiler and improved the load regulating ability in extent,but the regulating rate is not quick enough to meet the requirement of grid.Since“Two Rules”were came up with by North China Regulation Bureau,State Electricity Regulatory Commission(SERC),rapid response ability of power plants is drawing more and more attention in contemporary coal fired power plants.In order to carry on an effective analysis by applying storage energy to enhance rapid regulation ability of power plants,researches on thesis below are proposed.1.Based on analysis of the process during condensate throttling,that is,condensate water flow varied,which leaded to the change of distribution of extracted steam and power output was regulated.A static model of regenerative system of power plant is proposed,and a verification using the real data in condensate throttling experiments is exhibited to prove the effectiveness of the model.2.The regulating ranges and maximum lasting period by using condensate throttling were investigated based on the static model,and parameters of dynamic model were discussed at the same time,which would insure the security of units in the course of regulating power output.3.The characteristic of typical power unit model and traditional coordinate control system were analysis.Based on the research above,a rapid load control system introducing condensate throttling was proposed and a comprehensive simulation was accomplished to reveal the rapid load regulation ability of novel control system.4.For a further verification of rapid load regulation ability of novel control system,a quantitative calculation for power output regulating process by using condensate throttling according to "Two rules" indicator to simulate the practice load regulating operating was proposed.In particular,control performances on the initial stage of regulation was focused on and discussed.