Optimization Of Generator Serial Start-up Sequence Considering The Flexiable Re-energizing Time Of Transmission Lines

The economic losses and negative social impacts caused by blackouts will increase with the length of the power outage.Optimizing the start-up sequence of the generators in the power outage system can significantly improve the power system recovery efficiency and make a great impact in reducing system power outage losses.Due to the generator start-up sequence optimization is coupled with the restoration path optimization,the existing generator start-up sequence optimization of mainly include: 1)Establishing a generator nonlinear coupling model between the generator start-up sequence and the restoration path,which is solved using intelligent algorithms,but its solution efficiency is low and convergence and optimality of the solution cannot be guaranteed;2)The generator start-up sequence optimization problem is decomposed into the generator start-up sequence optimization and the target generator recovery path optimization,which is solved iteratively,but it weakens the influence of system topology to the generator startup sequence and neglect the impact of delaying the recovery time of one generator on the recovery time of other generators,it is difficult to obtain the optimal restoration plan;3)constructing a mixed integer programming model for generator start-up sequence optimization that can take into account both the line topology and the unit properties.The method can improve the efficiency of the solution,but it requires that the re-energizing time of transmission lines must be set to the same value.It cannot flexibly deal with the situation where the re-energizing time of transmission lines is slightly different,and the optimization model can only provide a parallel generator start-up sequence which cannot meet the actual demand of early stages of recovery.Therefore,this paper constructs optimal model of generator serial startup sequence with flexible consideration of re-energizing time of transmission lines a mixed integer programming model.This article mainly completed the following tasks:Firstly,the nonlinear coupling model of generator start-up sequence and recovery path was studied.Aiming at the maximum total power generation during the system recovery process,taking into account the crank power constraints,cold and hot start time constraints,voltage and power flow constraints,and intelligent algorithms were used to solve them,and they are used in the IEEE-39 test system The simulation is performed that the solution efficiency is low and the optimality of generator start-up sequence cannot be guaranteed.Secondly,the iterative model of generator start-up sequence optimization and target generator recovery path optimization was studied.The crankng power linearization method of the generator was analyzed,the target generator recovery path decision model was optimized,CPLEX was used to solve it,and the simulation was performed in an IEEE-39 test system.The solution efficiency is high but the optimal generator start-up sequence cannot be obtained.Thirdly,a mixed integer linear programming model of generator serial start-up sequence with flexible consideration of re-energizing time of transmission lines that takes into account both the system topology and the properties of the generator is proposed.The characteristics of the operational status of the recovery path and node during the system recovery process were analyzed.A linear integer representation of the operational status of the recovery path and node was used to establish a mixed integer linear programming model of serial recovery of transmission lines.The hot and cold start-up time limit and frequency stability requirements wsa established.The IEEE-39 test system is taken as an example to verify the feasibility of the generator start-up sequence optimization model proposed in this paper,and compared with the existing generator start-up sequence optimization model to verify the effectiveness of the proposed optimization model.