| The training simulator has been widely applied in the power plant and nuclear energy plant. Its contrivance and application make an important role in the power plant's safety and economical operation. Although the main type units in our country already have their corresponding training simulators, the training simulator for 135MW unit is still scarce. Based on other simulator models and the analyses of the characteristics of 135MW unit, for the 135MW unit turbine system of Xishui power plant in Guizhou province, the dynamic mathematical model of the turbine system and its corresponding simulation model are constructed.Compared with 200MW unit, the 135MW unit turbine system has much difference in the turbine's main body structure, the lubrication oil system, the axis seal system, the plywood and flange heating system, the speed monitoring system, the supply water system, the ancillary steam system and the condensing and circulating water system. The old mathematical model is greatly modified in this paper. For the high-pressure and low-pressure heating system, the deoxidizing system and the ejecting water and extracting steam system, the major changes are the operational parameters and the characteristic curve. The main differences and solutions are presented as following:â‘ The high-pressure cylinder is integrated with the mid-pressure cylinder in the turbine's main body. The leaking steam in high-pressure cylinder's previous axis seal is divided into two parts: one part leaks to the No 2 high-pressure heater, the other part comes into the back of the mid-pressure cylinder adjusting valve. Therefore, the simulation model for the turbine's main body, the axial pushing force and the vibration is exploited newly.â‘¡ For the high pressure feed-water system and the low pressure feed-water system, the methods such as using the overall heat resistance to calculate the heat transfer quantity, changing the heater water level and using the volume relation formula are employed and the calculation accuracy is good.â‘¢ The operating process of the deoxidizing system is thoroughlyanalyzed. The mathematical models of some parameters' dynamic change are provided. These parameters include feed water flashing, feculence discharged, the water level of the water tank, steam saturation pressure, etc.â‘£ The mathematical models for the condenser and circulating water system are revised by considering the conditions in the two systems. These conditions include: the coagulate water entering the condenser flashing, the water in heat-well evaporates or congeals on changed ejecting steam pressure, the water in heat-well submerges the pipe sheaf and affects heat transfer , the heat transfer area, the low pressure cylinder is a kind of structure of double cylinder with double ejecting room, etc.In terms of the constructed mathematical model, the simulation blocks for the turbine's sub-systems are programmed by employing Visual Fortran90 and are connected with other simulation blocks to form the simulator's whole model. By debugging for nearly two months and modifying and adjusting each part of the model, the model constructed in this paper meets the need for training employees. A series of disturbing experiments, such as load disturbance, the shut down completely the extracting air device, the cut off of high-pressure heater, the cut off of No.3 and No.4 low-pressure heater, are made on the simulator.By nearly half year's running of this simulator, it is confident to say that the constructed mathematical model and simulation model for the turbine reflects 135MW unit turbine system's work process and simulates exactly .the unit all work process. It acquires wonderful training effect...
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