In order to developing fault testing system in vehicle , the city railcar ' s electromotor parameters should be tested , collected and disposed in real time , so traction / brake power and electromotor moment can be calculated by " electrical current , voltage and rotate speed , and so traction / brake trait curve can be protracted . according to this , traction electrsmotor ' s working status can be got using fuzzy synthesis judge method , which provides bases for realizing electric traction system ' s fault diagnosis in city railcar 为了实现城市轨道车辆的随车故障诊断，必须对轨道车辆电机运行时的各项参数进行实时检测，并对检测到的参数数据进行采集和处理，根据牵引电动机的电流、电压和转速等参数值计算出在牵引制动工况下整车的牵引力制动力及电机力矩的大小，并绘制出各手柄位下的牵引制动特性曲线。
This thesis designs automobile braking performance inspecting and control system . this thesis consists of three main parts . something about automobile braking system design has been discussed in the first part according to the main requirement of gb7258 - 2004 《 the requirement for motor vehicle , running safely 》 . the hardware has been designed according to the characteristic of the parameter afer establish the whole plan for inspecting it . and then working principle of each part has been introduced . and at last , we designed software depending on the require to inspection and function . we can educe the braking power of both wheels , braking moment retardarce power and other parameters . we designed sensor signal processing circuit which including power sensor signal processing circuit and speed signal measure circuit according to the require of designing parameter . ad620 is used as power sensor . in order to measure the power of the automobile braking and protect the electromotor . so we must measure both 由汽车制动测试原理以及制动性参量检测的技术指标可知,检测数据准确性、控制可靠性、实时性和抗干扰能力是系统设计的关键。本文在掌握汽车性能检测系统结构和原理的基础上,根据国家有关标准和汽车制动性检测系统的控制逻辑提出了采用单片机为控制器的总体方案,设计了各部分硬件电路,并根据所要实现的功能用c51语言设计了软件。由于检测现场存在各种干扰噪声,为了保证系统运行的稳定性和可靠性以及测量精度的要求,分别从硬件和软件的角度出发,介绍了常用的硬件抗干扰措施以及软件数字滤波的原理和方法。
