Proportional valve control system of train car system test rig design and researchTrains are proportional valve can make the vehicles braking rate not along with the change of load change, keep a constant, to reduce the train braking on the longitudinal impulse, avoid empty with the braking force is too large to wheels, brake shoe, holding in death of the wheels sliding on the rail abrasion wheel, and heavy car due to insufficient braking force cant park within the prescribed braking distance. Because trains are proportional valve importance related to the personal safety, the quality put forward higher requirements, therefore to train load proportional valve test is also put forward more requirements. According to the properties of the sense of train load proportional valve, proportional valve testing test-bed design studied. Finally after the actual test shows that the test high test precision, stable performance, loading and unloading test parts quickly and accurately, short test time, test results, high degree of visualization, historical data query is convenient, can be developed for train sense of proportional valve and provide reliable testing basis and on-line detection methods.Railway is the artery of national economy, it shoulders the heavy task of passenger and cargo transportation. With the rapid development of economic and social progress, the railway passenger traffic volume continues to grow, the transport capacity of railway system is higher and higher requirements are put forward. In this case, in addition to need to put more rail lines, increase the speed of train is a more effective way to solve the capacity shortage. On August 1, 2008, the beijing-tianjin inter-city railway opened to traffic operation formally, marks the advent of the era of high speed train in China, more and more high-speed rail line will be opened in the future.Systems hardware design including pneumatic, electric control system, hardware test-bed control system optimization, etc. First of all, based on the sense of train load proportional valve performance test requirements, puts forward the initial scheme of circuit design, clear the design idea and method; Then, through the analysis of the ratio of the initial plan for the further optimization to improve; Finally, equipped with a pressure transducer, data acquisition card, etc. Main control parts of electric control system, finally completed the train load proportional valve control systems hardware design.According to train main test indicators, load proportional valve test rig must be able to provide for train sense of proportional valve, therefore, in this paper, on the basis of initial design, through the further optimization and improvement of the performance to price ratio, the formation of the final construction scheme optimum pneumatic circuit.Sense of train load is proportional valve need fast charging, exhaust, solenoid valve work frequency is higher, so generally use the MAC valve company production balance type multi-purpose valve control valve (EP), EP valve pneumatic circuit. Within the dotted line 2 2 2 2 EP solenoid valve and valve (6) constitute a wind, relief valve, controlled by the master control system of computer, also can through the control panel buttons (1) backup systems, pneumatic systems). Manual control charging ball valve , the exhaust valve constitute the standby system 2 (manual). To be measured when the valve train are proportional valve charging and exhaust air, measured by a pressure transducer signal pressure and output electric signals, and transmit to computer into pressure value, at the same time terminal pressure gauge display air pressure value directly, convenient for observation. Air supply pressure gauge shows gas source pressure, pressure gauge for regulating the load control counter pressure and signal control counter pressure. Precision pressure regulating valve external in the combination at the inlet of the valve , reduce the combination valve inlet pressure fluctuations, stability into the gas chamber pressure, which significantly improve the stability of precision. Precision pressure regulating valve of the pressure regulating pressure is higher, the pressure difference, the greater the signal the faster and more steady wind pressure rise. But the precision of pressure regulating valve regulating pressure is too high, is not conducive to signal pressure drop, after many test, precision pressure of pressure regulating valve will be dispatched to 700 kpa, makes the high pressure difference is higher, to signal the wind pressure of the steady and rapid rise, at the same time to facilitate the signal pressure of low pressure drop. Gas load volume 1 l capacity can slow the pressure and output fluctuation.Three channel control mode (computer control of automatic test systems, panel button manually test system, switch valve manually test system), and better satisfy the requirement of the test bench work. M