基于多能源互补的分布式冷热联供系统的数学建模及优化运行研究

发布时间：2018-03-06 18:40

本文选题：分布式冷热联供系统　切入点：多能源互补　出处：《华南理工大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着我国国民经济的高速发展及人们生活水平的日益改善，我国对能源的需求持续增长，由此而引起的环境问题也愈发严重。建筑能耗作为我国三大“耗能大户”之一，也呈逐年增长趋势，其中以供暖和制冷最为耗能。在节能减排和可持续发展的大背景下，冷热联供系统因其一次能源利用率高、排污量少等优点，被认为是一种能同时有效解决供暖和供冷问题的环保供能方式。本文通过对多能源互补与冷热联供系统进行有机结合，设计了一种基于多能源互补的分布式冷热联供系统，，实现对于风能、太阳能、天然气及电能的综合利用。首先，通过分析冷热联供系统可利用的能源种类，结合我国能源开发利用现状，确定了系统的能源利用形式。与此同时，通过对系统主要设备适用性的分析，完成了对设备类型的选择。在充分考虑能源特点及设备类型的基础上，分别建立分布式联供系统的子系统循环流程，包括供暖循环和供冷循环，最后得出联供系统的循环方案。与传统的分离供能模式相比，该系统集供暖及供冷于一体，冬季运行于供暖模式，而夏季则运行于供冷模式。另外，有别于传统冷热联供系统较为单一的能源利用形式，该系统将考虑多能源互补模式，即综合利用非可再生能源和可再生能源，以同时满足联供系统可靠性及可持续性的要求。其次，以分布式冷热联供系统为研究对象，建立了较为完整且详尽的系统稳态数学模型。系统的数学模型包括分布式冷热联供站、供水网管及终端负荷三大部分。其中冷热联供站包括离网型风力发电系统、太阳能热水锅炉、天然气热水锅炉、电热水锅炉、螺杆式制冷机及LiBr吸收式制冷机模型；供水网管包括网管压降及网管温降模型；终端负荷包括建筑冷热负荷、采暖散热器及风机盘管模型。然后，基于所建数学模型，本文进一步研究了以系统运行成本最小化为目标的优化运行策略。为了得到优化运行策略，文中建立了非线性优化模型，包括优化目标函数和优化约束条件，并利用群搜索优化算法（Group Search Optimizer, GSO）进行最优值的求解。基于优化运行策略，系统处于供暖模式时将实现对以下变量的实时最优控制：天然气热水锅炉出水温度、电热水锅炉出水温度、循环水泵流量。而当系统处于供冷模式时，则对以下变量进行实时最优控制：制冷机组运行台数、太阳能热水锅炉出水温度、天然气热水锅炉出水温度及二次泵冷冻水流量。为了验证系统的模型及优化运行策略，基于MATLAB的仿真工作已进行并完成，包括仿真参数设置及仿真结果分析与讨论。仿真结果充分证明了系统稳态模型的可行性及优化运行策略的有效性。仿真结果分析与讨论结果表明，优化算法GSO能够很好地求解非线性优化模型，以实现最优值的搜寻。基于非线性优化模型的运行策略能够向设备提供最优设定值，使其运行于最佳工况，从而最大限度地减少系统运行成本。最后，为了评估所设计系统的经济性及能效性，本文从运行成本和运行一次能耗的角度，对所设计系统与传统分离供能系统（包括天然气供暖系统和家用空调系统）进行了比较。比较结果证实了所设计系统在经济性及能效性上均有显著优势。基于两种不同供能模式在运行成本上的比较结果，本文进一步分析了所设计系统的投资可行性，分析结果表明所设计系统具有投资可行性，并且具有较短的投资回收期。
[Abstract]:With the increasing improvement of the living standards of the people and the rapid development of China's national economy, China's demand for energy is growing, environmental problems caused by the increasingly serious. Building energy consumption as one of the three "energy hungry" in China, is also increasing year by year, the heating and cooling energy consumption in the most. The background of energy-saving emission reduction and sustainable development under the combined cooling and heating system because of its high utilization rate of primary energy consumption, less emissions, is considered to be a kind of can effectively solve the problem of environmental protection of the heating and cooling energy supply. In this paper, through the organic combination of multi energy complementary and combined cooling and heating system. The design of a cogeneration system based on distributed and multi energy complementary, for wind, solar, natural gas and electricity utilization.
First of all, through the analysis of combined cooling and heating system can use the type of energy, combined with the present situation of exploitation and utilization of energy resources in China, energy system were determined. At the same time, through the analysis of the main equipment of the suitability of the system, completed the selection of equipment type. Considering the characteristics of energy and equipment types, were established distributed CCHP system circulation process subsystem, including heating and cooling cycle cycle, finally obtains the circulation scheme of the CCHP system. With the traditional separation of supply mode compared to the system of heating and cooling in one winter, running in the heating mode, and the summer run in the cooling mode. In addition, there are different from the traditional cooling and heating system of a single form of energy use, the system will consider the multi energy complementary mode, the comprehensive utilization of non renewable energy and renewable energy, at the same time for full FIFA system The requirements of sex and sustainability.
Secondly, based on the distributed combined cooling and heating system as the research object, established a steady-state mathematical model of the system more complete and detailed. The mathematical model of the system including the distributed combined cooling and heating station, water supply network and terminal load of three. Most of the cooling and heating stations including off-grid wind power system, solar hot water boiler, gas water heater electric boiler, hot water boiler, screw type refrigerating machine and LiBr absorption refrigeration machine model; water supply network management network management network management model including reducing pressure and temperature; the terminal load including building cooling load, heating radiator and fan coil model.
Then, based on the mathematical model, this paper further studies on the optimal operation strategy to minimize the cost of running the system as the goal. In order to get the optimal operation strategy is established in this paper. The nonlinear optimization model, including the optimization of objective function and constraint conditions, and using the group search optimization algorithm (Group Search Optimizer, GSO) was used to solve the optimal value the optimal operation strategy. Based on the system in the heating mode to achieve real-time optimal control of the following variables: natural gas hot water boiler water temperature, electric hot water boiler water temperature, circulating water pump flow. When the system is in a cooling mode, then the real-time optimal control of the following variables: the number of operating refrigeration units, solar energy hot water boiler water temperature, gas hot water boiler water temperature and the two pump chilled water flow. In order to verify the system model and the optimal operation strategy, base The simulation work in MATLAB has been performed, including the simulation parameters and simulation results are analyzed and discussed. Simulation results demonstrate the effectiveness and feasibility of the optimization strategy of system steady-state model. The simulation results are analyzed and discussed. The results show that the GSO algorithm can well solve the nonlinear optimization model, in order to achieve the optimal value the search operation strategy. Nonlinear optimization model can provide the best equipment based on the set values, which run in the best condition, thus minimizing the system cost.
Finally, in order to evaluate the economic design and energy efficiency of the system, this paper from the angle of operation cost and operation time consumption, the system designed with the traditional separation energy supply system (including natural gas heating system and air conditioner system) were compared. The results showed that the designed system has on the economy and energy efficiency of significant advantage. Based on two different energy supply results in the operating cost model, this paper further analyzes the investment feasibility of the design system, the analysis results show that the designed system has the feasibility of investment, and has a shorter payback period.

【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU83;TM61

【参考文献】