【作者】 梅程强；

【导师】 刘海波；

【作者基本信息】 吉林大学 ， 微电子学与固体电子学， 2008， 硕士

【摘要】 能源问题一直以来都是人们所关心的问题,而火力发电站的运作作为提供能源的一种重要形式,如何提高火力发电站的发电效率也就成为人们所密切关注的问题。本文主要研究的是火力发电站汽轮机末级蒸汽干度测量的数据处理方法,用以实时监控火力发电站汽轮机的蒸汽干度,从而达到尽可能的提高火力发电站的经济效益的目的。本文利用Verilog HDL硬件描述语言、Quartus II软件和Synplify Pro软件来设计计算汽轮机末级蒸汽干度的电路,并给出相应的仿真结果。首先利用Mie散射理论的结果计算出的水蒸气的相函数,通过查表并进行反演拟合得出汽轮机末级蒸汽中液态水滴的众数半径;接着根据蒸汽凝水粒子尺度的广义Gamma分布来计算液态水的含量;然后利用压力传感器和温度传感器所测得的汽轮机内部的气压和温度计算干蒸汽的含量;最终通过前面的结果以及蒸汽干度的定义求出汽轮机末级的蒸汽干度。更多还原

【Abstract】 Energy issues attract considerable attention at all times. The operation of thermal power stations is an important form to provide energy. How to improve the power generation efficiency of thermal power stations is a matter of vital concernment. In this paper, we focused on the method of data processing in the measurement of dryness fraction at the end of the turbine of the thermal power station, to monitor the dryness fraction in real time, thereby improve the economic benefit of thermal power plants as much as possible.In theory: First, we calculate the results of the vapor phase function using Mie scattering theory, and get the most probable radius of liquid water droplets at the end-turbine by the method of the look-up table and inversion fitting; Then according to the Generalized Gamma Distribution of the steam condensate water under the particle size, using the most probable radius of liquid water droplets we get before and using some related spectrum parameters to calculate the of liquid water content at the end-turbine; then using the pressure and temperature in the steam turbine and according to the ideal gas equation to calculate the dry steam content, the temperature and pressure is measured by temperature Sensor and pressure sensor in the turbine; At the end, use the liquid water content, dry steam content and the definition of dryness fraction to calculate the dryness fraction at end-turbine.In the specific design process: We first define a framework of the overall design, it includes six sub-modules, and they are the Serial to Parallel data conversion module, the Clock Generation module, the most probable radius module, the liquid water content module, the dryness fraction module and the Register output module. Then we design these six modules, synthesize and simulate them using Verilog HDL (Hardware Description Language), Altera’s FPGA integrated development environment Quartus II and Synplicity’s FPGA synthesis tool Synplify Pro. In these six parts, Register output module is directly integrated into the overall design of the final, need not separate design. The dryness fraction module is separate of two sub-parts: the dry steam content module and the dryness fraction module. Through the design and simulation of these sub-modules, and we analyze the simulation results, the design of these modules are in line with our design requirements. At the end, we integrate these modules together, and supplement by some other logic elements to structure the top-module, and synthesize and simulate the top-module. We find this overall design using a total of 4,935 logic elements, which is 81% in the entire FPGA chip we used; Using a total of 49,152 memories, which is 81% in the entire FPGA chip we used; Using a total of two phase-locked loops, exhausted all the internal phase-locked loop of the FPGA chip. For the input ports: the five angle corresponding phase function, the related spectrum parameters of Gamma distribution, the pressure getting from the pressure sensor at the steam turbine inside, the temperature getting from the temperature sensor at the steam turbine inside, it will give the corresponding value of dryness fraction in a certain clock cycle (about 30 ~ 50 clock cycles). Real-time monitoring can be achieved at the end-turbine, preparing for the Realization of this design in related FPGA chip, providing a guarantee for the entity to monitoring the dryness fraction at the end-turbine of thermal power station.更多还原