Research On Energy-saving Operation Control Strategy Of Low-Floor Vehicle

With the rapid development of urbanization, low-floor vehicle become heavily favored in many big cities because of its low cost, humanization design, well urban landscape and so on, and it will be the development trend of urban traffic. So the research on energy-saving operation control strategy of low-floor vehicle has a great significance to build a resource-conserving and environment-friendly society. Energy consumption for traction and reuse of regenerating energy has important effects on the total energy consumption. In this paper, both the energy-saving strategies for the single-train and coordinated operation of multi trains are studied with the reuse of regenerating energy counted.The train group formation of low-floor Vehicle is introduced first, which demonstrates the necessity of the research by showing difference of characterization with other models and prepares for the deduction of energy-saving control strategy. Mathematical model for single-train is established, and the optimal control principle is worked out by using the Pontryagin principle and Hamiltonian function. The energy-saving control algorithm is designed, and the relationship between energy consumption and the highest speed is obtained by using this method on the Maple platform in ideal conditions, which prove the existence of minimum energy consumption. The software on the basis of Linux is designed, which can works out the energy-saving operation curve, and the result is analyzed.On the basis of single-train’s model, the mathematical model for multi-trains’ coordinated operation is established. The energy-saving control strategy is obtained by analysis under different circumstances, namely energy-saving control strategy with four modes of train movement (consisted of maximum traction, cruising, coasting and the maximum braking) and energy-saving control strategy with five modes of train movement (consisted of maximum traction, cruising/coasting, maximum traction, coasting and the maximum braking). With two trains running in the same power supply range as example, the heuristic algorithm design is used in the design of energy-saving control software, which can calculate the energy consumption of every energy-saving control strategy under different departure intervals. It is concluded through comparative analysis that the optimal energy-saving control strategy can be obtained with the departure time given, and the departure time and energy-saving strategy corresponding to the minimum energy consumption can be worked out too.Finally, it is converted from the train’s translational system to the rotary system of the traction motor, which is equivalent to the lab motor by the energy equivalent principle. Then the experiment is performed on the Reciprocal power-fed AC drive test system. The program in the upper computer is based on the Lab VIEW software, which sends communication instruction through serial port. The strategy of single-train energy-saving control strategy is tested in the experiment first. Then the test system for two trains’ coordinated operation is designed to imitate that two trains are running under the same power supply range. The energy-saving control strategy for multi trains is tested on this testing system, the results of which are in accordance with the simulation results. So the target of energy-saving operation for multi trains is realized by using energy-saving control strategy with four modes of train movement and energy-saving control strategy with five modes of train movement.