Research On Energy-Saving Optimization Technology And Modeling Of Energy-Fed Power Supply System

With the rapid development of my country's society,the city's demand for rail transit is also increasing.In the urban rail transit power supply system,the recovery and utilization of train regenerative braking energy has always been a research hotspot.During the operation of the energy feeding power supply system,the external characteristic parameters of the medium voltage energy feeding device will have a greater impact on the energy flow of the entire system,especially the utilization of regenerative braking energy.In this paper,the system's offline optimization and online optimization schemes are proposed.By optimizing and adjusting the external characteristic parameters,the purpose of energy saving optimization of the entire traction power supply system is achieved,and the influencing factors of the energy saving effect are analyzed from the two aspects of departure interval and AC low-voltage load.The main work of this article is as follows:First,the structure of the energy-feeding power supply system is analyzed,and the whole system is divided into an AC part and a DC part,and each part of the system is modeled separately.During the modeling,the working characteristics of the diode rectifier unit and the medium voltage energy feeder were fully considered,and a more accurate model of the traction substation was obtained.The overall framework of the system simulation platform is proposed,and methods for train operation simulation calculation and power supply system power flow calculation are proposed.The model and simulation algorithm of the system are verified through the simulation examples of specific lines.Secondly,the offline energy-saving optimization of the energy-feeding power supply system is studied.From the perspective of energy flow in the system,the influence of the inverter droop slope,turn-on voltage and equipment capacity on the energy flow of the system was analyzed.The fitness function was established from the perspective of system energy consumption,train brake shoe wear and equipment investment cost.Using simulation platform and genetic algorithm,the system was optimized under a variety of departure intervals and AC low-voltage load conditions.Through comparison,the causes of the departure interval and the influence of low-pressure load are analyzed,and the law of the external characteristics of the device is obtained.Finally,the online energy-saving optimization scheme of the energy-feeding power supply system is studied.By continuously collecting load data to adjust the external characteristics of the medium voltage energy feeder,the intelligent cloud processing system is used to realize the transmission of load data and the issuance of the external characteristic commands of the medium voltage energy feeder.The optimization algorithm and fitness function are adjusted,and a method to accelerate the convergence speed of the algorithm is proposed.Through simulation,the results of online optimization are simulated and compared with the results of offline optimization.44 pictures,20 tables,53 references.