Optimal Transmission Switching In Unit Commitment With Spinning Reserve Optimization

With the increase of high renewable energy penetration level,a large amount of reserve is required and the reserve resource would become more and more costly.Therefore,it is urgent to exploit the flexibility as much as possible from the power system to suppress the uncertainty introduced by the renewable energy generation.This research studies the reserve optimization problem considering the Optimal Transmission Switching(OTS).OTS incorporates the control of transmission assets into the schedule problem to co-optimize the network topology and the units output power simultaneously.Previous research has shown that transmission sw:itching is a meaningful measure to explore the flexibility and reduce the operation cost.However,only a few research focus on using OTS to improve reserve deployment and increase the utilization of wind power under uncertainty.In this study,two different stochastic models are proposed to optimize the Spinning Reserve(SR)requirement based on Unit Commitment(UC)model with OTS.a)The OTS actions are incorporated in the UC with a probabilistic SR criterion,and the optimal SR amount is determined by minimizing the total cost where the cost related to the expected load not served(ELNS)is penalized in the objective function.b)A UC problem considering wind uncertainty is combined with OTS to facilitate the available wind power integration.The amount of SR is calculated according to the largest deviation between the post and pre-contingency generation levels.This dissertation also analyzes the computational complexity of proposed models and presents new heuristic measures to improve the computation efficiency.One heuristic measure recommends a transmission line categorization module for choosing the best switchable lines according to the impact on the total costs associated with switching off a particular line,and another heuristic is used to find the optimal value of the maximum number of switchable lines in each optimization period.The case studies illustrate the validity and effectiveness of the proposed methods,and the simulation results reveal a significant improvement in terms of total cost and the SR deployment using OTS.