Transmission Network Expansion Planning Based On Bi-level Programming

From the traditional transmission network expansion planning (TNEP) to the market-based TNEP, the bi-level programming is utilized to build several bi-level programming models for TNEP in this paper. The models are deepened from simple to complicated and from certain programming to uncertain programming. The innovations of this dissertation are as follows:1) A traditional TNEP model considering economy and reliability based on certain bi-level programming is presented, the upper level program objective of the model is transmission investment cost minimization,the lower level program objective is load curtailments minimization when transmission system works in normal way and N-1 operation, which searchs economical and highly reliable optimal transmission planning scheme. Furthermore, minimum system overload under N-2 operation is considered in lower level program based on the above model to search economical and more reliable optimal transmission planning scheme.2) A dynamic TNEP model considering transmission profit based on certain bi-level programming is presented to search optimal transmission planning scheme with high transmission profit in double bidding based pool market style. The upper level program of the model is to make investment strategy from long-term planning, its objective is transmission profit maximization in planning stages. The lower level program is to make transmission price from short-term market operation, which establishes marginal cost price model based on social cost minimization.3) A TNEP model considering cost based on expected value bi-level programming is presented, the model uses expected value objective and expected value constraints to describe the risk from generators candidate and future load changes uncertainty, which searchs optimal transmission planning scheme with low investment cost and low operation cost and high flexibility. The model has two parts that are transmission network investment decision and power production optimal decision, the upper level program objective is the investment production and operation cost minimization,, the lower level program objective is the expected value of power production operation cost minimization, the lower level program constraints are system normal operation constraints and N-1 operation constraints and expected value constraint of system load curtailment under N-1 operation.4) A generation and transmission coordination planning model considering market benefits based on multi-objective chance constrained bi-level programming is presented, which harmonizes the conflict between generation planning and transmission planning and considers the equilibrium of profit between power generation company and power transmission company based on social welfare maximization. The upper level program objective of the model is maximization among generation chance index optimistic value and transmission chance index optimistic value and society chance index optimistic value, the lower level program objective is society chance index optimistic value maximization, which searchs optimal location of power plants and transmission planning scheme considering different market benefits in uncertain environment.5) A TNEP model considering return rate maximization based on dependent chance bi-level programming is presented to search optimal transmission planning scheme with high return rate and big realized probability. The upper level program objective of the model is realized probability maximization which transmission investment return rate is bigger than one realized level,the lower level program has two problems, the one is that the maximum social profit model when system works in normal way, the second is that realized probability maximization model which system load curtailment is less than a given value under N-1 operation.The 18-bus system and the 77-bus system are used to verify the proposed model in the paper, Monte-Carlo method is adopted to simulate the uncertain parameters, a hybrid algorithm integrated improved niche genetic algorithm and prime-dual interior point method is used to solve the proposed models, comparison and analysis of the results under several models are verified that the proposed models and methods are right and effective. Anyway, TNEP models based on the bi-level programming and methods give a new idea for TNEP problem in electricity market environment.