Study On Control System Of The Weighing Adjusted Spring Test-bed And The Spring Adjustment Algorithm Design

Railway is one of the main transportation modes in China. As axel loads and speeds of railway vehicles increasing rapidly, their dynamics performance has been put forward higher requirements. The wheels and axles’load distribution play the majoy fator to the dynamics properties and safety of locomotive and car. Too much weight deviation of the locomotive’s wheels or axles will make the wheels idling or slipping, and at the same time, high frequency torsional vibration will occur at the axles, which will make the locomotive traction and braking performance deteriorating significantly. Therefore, axle load deviation and wheel weight bias must be strictly controlled in vehicles’s design and production process. The standard GB/T3317-2006provisions that the axle load deviation of China’s railway running locomotive should not exceed the average axle load of±2%, and the deciation of the wheel weight should not exceed the average wheel weight of the same axis of±4%.In order to meet the increasing demands of the locomotive and car’s quality, railway industry is seeking to improve the technology of locomotive and car’s weighing and spring adjustment. Based on the development of a vehicle weighing and spring adjustment test-bed, this paper presents the design of the test-bed electric servo control system and an arithmetic for spring adjustment.In this paper, we researched the development of the technology of vehicles weighing and spring adjustment, then eventually chose a mechanical system after compared its advantages and disadvantages with hydraulic systems.In the mechanical system, the lifting and weighing structure is a mechanical structure, the control system is an electic servo control system,which uses servo controllers and the PLCs drive and control rotation of the motors to make the weighing platform moving and lifting. The test-bed control system’s hardwares consist of motion control modules, counting modules, communication modules, the control desk, IPC and electrical cabinets etc. The paper alse introduces the control system, including servo-driven, position detection and control, PLC control and electrical control etc.Based on Delphi programming environment, the Control/Management system of the test-bed is accomplished with a nice human-computer operation interface. The system has the following functions:user management, configuration, machine adjustment, maintenance, test, data query and print, online help etc. The Control/Management system communicates with the machines through the OPCServer. By real-time accessing to datas in the OPCServer and processing to achieve real-time display of weight parameters, as well as real-time alerts. Through the combination of the UML model which based on the Bold for Delphi and Access database technology, the test results can be saved and managed well.Another important work of the paper is the design of the spring adjustment. By analyzing the mechanical model of locomotive,an arithmetic for spring adjustment was got, then we reslized the algorithm by Matlab and did simulations. The spring adjustment arithmetic was embedded into the Control/Management system by hybrid programming between Matlab and Delphi, so we can use it to calculate and analyze the datas during test.