Electric Control System Of Subway Vehicles Based On LCU Reform Design

With the vigorous development of the urban rail transit industry in recent years,there is demand for subway vehicles with larger number and higher quality.The existing electric control system of the metro vehicle uses a contact scheme represented by a relay to control and achieve the activation of the driver’s cabin,traction application,brake control,and so on.Each subway vehicle has several hundred relays.This solution has many shortcomings such as high cost,high failure rate,no redundancy in logic cascade,poor flexibility of the circuit and wiring,low overall reliability of the program.There are more and more late-arriving accidents due to relay failure in recent years,which seriously affects the operation efficiency of the MTRC and citizen satisfaction.With the rapid development of electric and electronic technology,microprocessors and switching components become more mature.The non-contact electronic control loop,represented by LCU logic control unit has many advantages such as low cost,low failure rate,ability to directly drive the load,redundancy and self-diagnostic capabilities,flexible control,easy maintenance,high reliability,and so on.Besides,Although there are few applications related to LCU in the field of metro at present,the use of LCU to replace the traditional contact-controlled loop with relay as the core has become the development trend of the next-generation metro vehicle control field.Aimed at Guangzhou Metro Line 13 subway vehicles(provided by CRRC Dalian Locomotive Co.,Ltd.for the Guangzhou Metro Group),This thesis focuses on the LCU logic control unit to replace its previous replacement relay control scheme.First of all,the original relay control circuit of Guangzhou Metro Line 13 is analyzed,including the circuit of battery power supply circuit,driver’s room activation circuit,and so on.After that,the range of relay replacement is determined by the analysis of various control circuits based on the actual situation of Guangzhou Metro Line 13 vehicles,the overall LCU retrofit program is further designed to determine working conditions,technical parameters,design of electrical schematics,and redundant design.Based on this,the composition and selection of the LCU retrofit hardware were completed,including the selection of the power board,the main control board,the DI/O board,and the communication board.Then,LCU reformation software were further designed.Finally,the prototype was measured and verified,and through the prototype loading,the actual operation of vehicles running together assessment,LCU transformation program and relay program reliability prediction and full-life cost forecast were compared to prove that LCU transformation meets the requirements,and has many advantages such as the technology,the economy and has the value of increasing promoting the use of this project in future.