Study On Relevant Issues Of Power System Planning And Reconfiguration In The Environment Of Energy Saving And Emission Reduction

Since reform and opening, under the correct leadership of the CPC Central Committee, China, as the world’s fastest growing developing country, has made remarkable brilliant achievements in economic and social development, improving the people’s living standard significantly. However, due to long-standing inefficient use of energy, technical conditions backward, irrational industrial structure and other factors, China has been paying high cost of excessive resource consumptions and serious environmental damages for the achievements. The contradiction between the requirement for economic and social development and the crisis of energy shortage and environmental polutions is becoming increasingly obstructive to China’s sustainable development. Energy conservation and emission reduction is the only way to ensure long-term interests of the Chinese nation, and also the response to the global energy crisis and climate change which is urgently needed.As the main consumer of primary energy and supplier of secondary energy, electricity system plays the most important role in the energy conservation and emission reduction task. Facing the deepening energy conservation and emission reduction projects, the power system is ushering in a new series of changes and new problems and requires some new approaches for research and analysis. In this context, this dissertation takes energy conservation and emission reduction as the fundamental starting point, and focuses on several key issues that are closely related with electric power system planning and operation, including the improvement and expansion of power system carbon emission flow analysis theory, life cycle analysis of carbon emission transfer in Chinese power supply system, optimal distributed generation planning, distribution system reconfiguration with distributed generatiors, and risk assessment and uncertain decision-making of power system investment.Firstly, the carbon emission flow analysis theory for power system is improved and expanded taking into account the power loss and carbon emission responsibility allocation in the dissertation. Combined with life cycle assessment methods, the improved carbon emission flow model is used to account the carbon emissions and analyse the characteristics of carbon emission transfer in China’s power supply system, including cross-regional coal transport and electricity transmission. The analytical results are compared with previous research results. According to the results, differetiated treatments upon different regions and interregional economic ties from carbon emissions are suggested for the policy formulation of China’s electricity supply system energy conservation and emission reduction.An integrated optimization model is built to solve the distributied generation planning problem in the distribution system. The objective functions not only take the economic costs and distribution system power losses into consideration, but also maximizes the benefits of energy conservation and emission reduction using life cycle exergy consumption as a unified indicator. This indicator comprehensively measures the resource consumptions and environmental impacts caused by distributed generation and the effect of substituting traditional energy sources. Chance constraints are used to simulate the uncertainties of distributed power output and load. The Latin hypercube sampling probabilistic load flow analysis is improved by conbining with linear load flow equations. The voltage vector is calculated by linear load flow equations which is proved to be efficient and accurate, avoiding time-consuming iteration process. The branch load flow vector is calculated by the nonlinear equations ensuring the accuracy. Based on the proposed semi-linear Latin hypercube sampling probabilistic load flow analysis method, the probabilistic load flow analysis method considering asynchronous wind power generators is improved. Based on such probabilistic load flow analysis method, an optimal reconfiguration model is established to solve the distribution system reconfiguration problem considering distributed generators and uncertain power loads. The genetic algorithm is improved to solve the optimization model. Finally, the IEEE-33bus distribution system is used to illustrate the proposed models and methods.The uncertainties of energy conservation and emission reduction polies bring more risks for electric power investments. To improve the accuracy of power investment risk assessment, the Nataf transformation is used in the stochastic simulation process to simulate the correlations of uncertain factors. Meanwhile, on the basis of risk assessment, probability characteristics of criterion values and criterion weights are added to the sensitivity analysis for power investment decision making, constructing probabilistic sensitivity analysis method. Practical case studies are carried out to illustrate the effectiveness and applicability of the proposed methods.