| With the increasing pollution of the world and the increasing shortage of fossil fuels, the development and utilization of renewable energy has become the focus of research in the world. Distributed generation technology is a kind of technology which can generate electricity according to local energies and resources. As the core part of the distributed generation technology, the cogeneration equipment takes the responsibility for the conversion of the new energy into the power output. Energy supply system is one kind of system which uses the cogeneration equipment as the core part, can realize energy cascade utilization, and contains multiple distributed generation and energy forms. It has multiple advantages such as high utilization of energy, flexible control, better economy, low polluted emissions, and high power supply reliability and so on, which make the energy supply system become the research focus of many countries. In this dissertation, we take the combined cooling, heating and power system and integrated energy as two typical systems of the enrgy supply system, which both use gas turbine as the cogeneration part. Studies of optimal configuration of the two systems were carried out, and the main structure of the dissertation is shown as followed.Firstly, the development and research status of the energy supply system was present. Mathmatical model of the congeneration equipment (gas turbine and PV battery) and auxiliary equipment (absorption chiller, electrical chiller, gas boiler and thermal strorage tank) are established. The thermal and power efficiency of the gas turbine both change with the part-load ratio, which makes the model of the gas turbine nonlinear. Probability model is applied to PV battery to deal with the stochastic simulation.Secondly, study of the optimal configuration of the combined cooling, heating and power system is carried out. An optimization model of the CCHP system including gas turbine, PV battery, thermal storage tank, gas boiler, absorption chiller and electrical chiller is established, which takes the economy as the objective. The uncertainty of the cooling, heating and power load and the PV power is simulated by the Mente-Carlo simulation technology and the model is solved by the Particle Swarm Optimization (PSO).Three different configuration schemes are proposed to analyse the different influences on the system capacity. Different impacts of the uncertainty of the cooling, heating, power and CHP load on the system configuration are analyced and compared. Frequency distribution of total costs and each facility are given, and the feasibility of the given model and algorithm can be proved threogh the matching degree of the frequency distribution and the normal distribution curve.Lastly, study of the optimal configuration of the integrated enrgy system is carried out. Model of integration energy system comprising electricity network and a correspondingly designed water system is established with DG coupling of thermal and electrical energy. A study of optimal configuration of the system while supplying the multiple energy demand is carried out, with the objective of minimizing the total costs of investment and operation. PSO algorithm is employed to simulate the proposed model. Optimal configuration results of the single distribution network and the integrated energy system are compared, which indicate the impact of the integration of the thermal network on the configuration results. The utilization ratio of the optimized DG is shown to analyze whether the optimal sizing of the DG is reasonable or not. The separate production system is adopted to be compared and analyzed in regards to the voltage level and the net loss with the single distribution network and the integrated energy system.The work done in this dissertation can provide suggestions to the optimal configuration, improve economy, energy efficiency and environment benefits of supply energy system, increase the integration capability of renewable energy into the system. |
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