Online Calculation Based Research Of On-board ATO Operation Type Profile Optimization Model

On-board ATO (Automatic Train Operation) is the core parts equipment of automatic train control. It is an advanced train control equipment and demonstrates the intelligence of rail transport. Automatic speed control is one core functions of ATO, usually, it is realized through the combination of the operation type profile calculation module and the module of automatic speed control. After taking comprehensive consideration on time, accurate parking, energy saving, comfort, track condition, train performance etc, operation type profile calculation module will calculate the best train operation track based on the programmed operation time and operation paths. Automatic speed control module control train operation according to the operation truck. The operation type profile calculation module has two different models:on-line and off-line. The online calculation module can improve the adaptive capacity of ATO, which is able to obtain real-time information and adjust the operation in time during the operating process.The online calculation of operation type profile is a high real time capability of multi-objective optimization problem. After analyzes and summarizes the existing multi-objective optimization algorithm and on the basis of the dynamic programming principle of optimality, the method of the thesis is to divide the profile into a number of interrelated phases according to the operation time. At each stage, using multi-objective hierarchical decision to calculate the optimal solution and achieve the optimizing of ATO operational mode profile.The main works of this thesis can be surmised as the followings:1. According to the characteristic of train operation and control target, the thesis establishes the mathematical model system of train operational control. The mathematical model system includes the optimized model of train kinematics, the calculation model of control parameters, the calculation model of control target, the evaluation model of control target and the state transition model of train operation, etc.2. To overcome the shortcomings of single subjective and objective weight existing in solving the optimization problem, this thesis proposed the model of ATO controlling target weight calculation and weight combination calculation based on subjective weights, local objective weights and objective weights.By dividing ATO control objective weights into local objective weights and global objective weights can realize the description of different stages of objective factors impacts on the stage performance and the overall performance. Through changing the combination plan of subjective weights of objective weights, local and global weights of objective weights, the decision will directly influence the outcome of multiple objective decision making, and finally achieve the expected purpose of optimization3. The thesis proposes the idea of ATO multi-objective hierarchical decision method and divided Multi-objective decision-making into two layers according to features of the Punctual, precise Parking, energy-saving and comfort-objective optimization. The function of first layer of multi-objective decision is only optimizing the energy efficiency and comfort goals and make energy efficiency and comfort s be the optimal; The second layer is used to Optimize punctuality, precision Parking, energy-saving and comfort index and makes punctuality and precision Parking s satisfy the constraints through the expense of energy efficiency and comfort index.Multi-objective hierarchical decision between the two layers of multi-objective decision-making proposed in the thesis is independent from each other. It optimizes energy efficiency and comfort index before optimizes all the index and judge whether the optimization results meet punctuality and precision parking constraints and realize the purpose of maximizing enhance energy saving and comfort index under the premise that punctuality and precision parking index is not affected.4. The on-line calculation of ATO best operational type profile is a multiple optimization problem, which has the characteristic of high real-time, multiple target, nonlinearity of control system and various and complex environment obviously effect on control targets.Based on the mathematical model system of train operation, using the idea of multi-objectives comprehensive optimization based on multi-level decision, this thesis proposes the on-line calculation model of ATO best operational type profile. Through the experimental simulation, the on-line calculation model of ATO best operational type profile can satisfy the real-time and optimization requirements, which has certain positive significance in the field of technological progress.