| Distributed Combined Cooling Heating and Power System (CCHP) develops as a novel energy supply way around the world in recent years, which achieves energy cascading utilization, boosts the total energy efficiency and is regard as an environment-friendly, economical and reliable option for the future. The systems with reciprocating internal combustion engines and thermally-activated cooling technologies are the issue of commercial applications and scientific researches. However, because of its unique characteristics, this type of system still draws many concerns while it is viewed as a sophisticated technology in developed countries. The new research issue lies on system optimization of design, evaluation, control and operation. Consequently, this thesis deals with multi-objectives as design optimization, evaluation optimization and control optimization of CCHP based on thermodynamics, thermo-economics and integrated process technology. The study also combined with practical applications in several commercial and experimental systems, which realize system optimization with those theoretical results. In sum, this study provides a method for better designing and utilizing distributed combined cooling heating and power system, which would be beneficial for its development and the goals of energy-saving and energy security in a long term. The major work is listed as follows:(1) Analyze and evaluate different CCHP systems based on thermodynamics and thermo-economics (including the criteria of the first and second laws, and economic exergy theory). It is concluded from the first law analysis that part load performance of equipments, characteristics of user's demands, price ratio between various energy and some other factors have the crucial influence on CCHP performance. Compared with conventional energy systems, CCHP in both summer and winter conditions can achieve 20% energy saving. In exergy analysis, it is revealed thermally-activated cooling technology is important for CCHP. The exergy efficiency of adsorption chiller is higher than that of electrical chiller around 10%, and the economic exergy efficiency of CCHP with adsorption chiller reaches 36% and 25% in winter and summer respectively. Besides, various operation modes of CCHP are compared in particular circumstance, then, optimized operation mode is obtained. After analysis with different theory and criteria, an improved entropy information-analytical hierarchy process is applied to conclude all the criteria in a comprehensive evaluation, which is meaningful for CCHP system analysis.(2) Improve integrated process technology in chemical industry, use the improved Pinch Analysis (PA) to retrofit and design CCHP systems. According to two practical cases study, the new PA can not only retrofit existed heat exchanger network, optimize placement of heat engine and heat pump, but also determine core equipments, design new system based on"onion model"of chemical engineering. The new PA solves the problems of discontinue streams, pseudo pinch point, heat pump and heat engine placement, and the Threshold problem in CCHP system. In a case, with proper placement of thermally-activated cooling equipment, the CCHP system promotes the efficiency by 13%.(3) Design a commercial CCHP system with combustion engine and absorption chiller for a hotel & office building complex. The main components include 155kW gas engine, 700kW exhaust gas driven absorption chiller with supplement burner and 930kW gas boiler. The engine jacket cooling water loop and exhaust pipe are redesigned for waste heat recovery. The operation proves the system fits for the user's demands and it can achieve large amount energy and expenditure saving for the user.(4) Design a set of Centre-Distributed Control System (CDCS) for a CCHP application. The upper layer of CDCS applies configuration software-KingView, which executes energy management; the lower layer is comprised of industrial PLC with the function of real-time control. During one year's operation test, the CCHP system under CDCS's controlling meets instant 3 to 4 kind of demands and PER is 85% in winter and more than 1 in summer. Compared with conventional systems, the CCHP saves 10~20% fuel energy and around 20% energy expenditure for the user.(5) Experimental data analysis and CHP module simulation of a large CCHP application located in German Parliament House and several large buildings around in Berlin. The large CCHP is comprised of diesel engines, absorption chillers, boilers and electrical chillers. While waste heat form prime mover is fully recovered, the total energy efficiency is more than 80%. Through mass experimental data analysis, the important system parameters are calculated by MATLAB program. The simulation model of CHP with Simulink can further simulate the operation process of the CCHP, which is the keystone of building real-time process simulation software for CCHP systems. The simulation results also can be viewed as useful references for optimization design and evaluation.
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