Analytical Study on the Problem of Abnormal Application of Air Brake on CRH6 Intercity EMU
The issue of rapid wear of brake pads of CRH6 intercity EMUs during operation has emerged,with the wear cycle of about 80,000 kilometers.According to the deceleration design curve and the electric braking envelope,the electric braking capability of the train can cover at least 2 levels of commonly used braking in the full speed range.However,a large amount of online operation data show that EMUs are supplemented with air brakes in the low-level position(level 2)braking,which is different from the theoretical design.To address these issues,a ground test bench for the traction and braking systems is built.In order to simulate the conditions of the existing car,the length of the electric brake request and electric brake feedback cables is the same as that of the existing car.It simulates the electric-pneumatic matching working conditions under different braking level positions and different speed grades,and utilizes the upper machine and multimeter to collect the electric braking request value and feedback value of the traction control unit(TCU)and brake control unit(BCU)respectively.Through analyzing,studying and comparing the test data,it is found that the A/D circuit and D/A circuit inside the TCU and BCU have losses in the conversion process.In addition,there is also attenuation in the load signal transmitted between the motor car and the trailer within the same braking unit.Therefore,starting from the brake control principle,this article puts forward an improved optimization scheme for the train that adopts the hard line as the transmission medium of electric braking and air braking,and sets the electric braking compensation coefficient inside the TCU.The optimization scheme has been verified by the present train,and the application effect is good.
intercity EMUbrake control unittraction control unitcompensation coefficientelectric brake requestelectric brake feedback
万方数据
维普
