Shrink Predictive Control Based Multi-objective Speed Planning Of High-speed Train

Automatic train control system has become a research hotspot in the rail transit industry.The key of the research on the automatic train control system is the planning of reference speed trajectory during the train operation.With the increase of energy prices,environmental protection pressure and transportation volume,a reference speed track that can ensure the safety,punctuality,comfort and energy saving of train operation can greatly improve the operation efficiency and departure density of the train.On the basis of reviewing and summarizing the relevant domestic and foreign literature,the paper takes into account the speed trajectory planning of high-speed trains,the model predictive control method is adopted to study the multi-objective speed planning of high-speed trains based on the shrink predictive control.The main research work of this paper is as follows:In the first part,the kinematics model of the train is established firstly based on the basic theoretical analysis of the train's operation process.Secondly,according to the operation characteristics and physical structure of the train,the main factors affecting the energy consumption of the train operation are analyzed and the train energy consumption model is established.Then,according to the requirements of train operation,the evaluation indexes and operating constraints are analyzed.In the second part,in order to ensure the running performance of the train,coordinate the relationship between the safety,punctuality,comfort and energy saving,a multi-objective model predictive control optimization problem is constructed.After that,in order to effectively ensure the accurate parking of trains under various uncertain disturbances,a shrink receding horizon strategy is proposed according to the operating characteristics of rail trains.In order to solve the problem of optimal speed planning in the process of train operation,Radau pseudo spectral method(RPM)is introduced to discretize the continuous kinematic model of train and improve the accuracy of train speed trajectory planning.A multi-objective speed planning algorithm based on the shrink receding horizon is designed and the recursive feasibility of the algorithm is analyzed.Finally,the effectiveness of the algorithm is verified by simulation.In the third part,in order to improve the real-time performance of train speed planning online,the multi-objective performance index of train speed planning is considered,and the multi-objective speed planning problem is constructed.Then,aiming at the problem that the model predictive control method takes a long time to solve in the complex and fast system,a move blocking method which can reduce the dimension of state and control variables in the optimization problem is introduced to reduce the computational complexity of the train speed planning problem.Then,in order to ensure the accurate stopping of the train,a new shrink move blocking strategy is designed based on the shrink receding horizon strategy proposed in the second part of this paper.Finally,an algorithm of train multi-objective speed planning based on shrink move blocking is proposed to improve the real-time performance of train speed planning.