| With the rapid development of China's economy and the continuous progress of the urbanization process, as a fast, stable and comfortable means of transportation, like a raging fire in subway construction in the major city.Due to the heat spread into the subway station, generated by the movement of subway, the heat radiation of equipment in subway station, and the body heat,rising the temperatures in subway station, it cause a great impact on the comfort of passengers. In the summer, it is not enough to ventilation and cooling rely on the outside air brought by piston wind, and the environment regulation in subway station should be realized by using the subway environmental control system. Although the subway environmental control system plays a very important role in improving the air quality of subway station, that growing energy consumption, as well as rising energy prices, resulting in increasing the subway operating costs, and have a serious impact on the economic benefit of subway operation enterprise. According to the relevant data of subway operation energy consumption, energy consumption of subway environmental control system accounts for 25% to 35% of the total energy consumption of the subway operation. Therefore, it is very urgent and necessary to study the energy saving methods and control strategies of the subway environmental control system. The major research findings and innovations of this paper are as follows:(1) The simulation of Fluent only can be aimed at the temperature field and the fluid field in the subway station, and it is difficult to realize the online control of the subway environmental control system. The simulation of Trnsys is easy to achieve the online monitoring of subway environmental control syste, but the assumption that the air in the subway station is evenly distributed as an air node can not effectively simulate the real environment of the subway station. So this paper put forward the Fluent-Trnsys co-simulation model to simulation the subway environmental control system combining the different advantages of the two software, using Fluent to simulate the fluid and temperature distribution of the subway station and Trnsys to simulate the equipment and control of the subway environmental control system.(2) It makes a depth analysis of the constant frequency control strategy using by the subway station for now and the variable frequency control strategy which is a kind of common energy conservation control strategy. For the problem of energy waste caused by the return air valve of subway environmental control system which is always in the normally closed state, this paper proposes a control strategy of return air volume based on the carbon dioxide concentration. With a subway training platform in Beijing as the simulation object, using Fluent-Trnsys co-simulation model make an experimentally compared between the constant frequency control strategy, the variable frequency control strategy and the control strategy of return air volume based on the carbon dioxide concentration. The simulation results show that compared with the constant frequency control strategy and the variable frequency control strategy, the control strategy of return air volume based on the carbon dioxide concentration has better control performance and energy efficiency.(3) Implement the PLC program and configuration monitoring interface of the control strategy of return air volume based on the carbon dioxide concentration. With a subway training platform in Beijing as the experimental object, compared with the variable frequency control strategy, inspection the control effect and energy saving effect of the control strategy of return air volume based on the carbon dioxide concentration. The experimental results show that compared with the variable frequency control strategy, the control strategy of return air volume based on the carbon dioxide concentration can achieve significant energy saving effect, under the condition of ensuring the comfort of personnel. |
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