车辆电模拟转鼓试验台动态特性研究

摘要

An electric dynamometer is widely used to reproduce road loads for vehicle tests, and many conventional vehicle tests on roads can thus be carried out on a test-bench using a chassis dynamometer. However, this requires that the vehicle's road loads under all working conditions are accurately reproduced. For this purpose a chassis dynamometer was designed to investigate all related performances. As it was very difficult to establish the theoretical model of a dynamometer for input-voltage and output-torque signals on wheels, the system identification method was used to fit the dynamic model of the dynamometer. Based on the dynamic model an optimal PID controller was designed. The experiments showed that both the dynamic characteristics and the steady-state error of a chassis dynamometer were significantly improved by the PID controller, and the dynamic response time without overshoot for step input was 0.27 second instead of 1.1 seconds by open loop controlling.%对电模拟转鼓试验台的设计及控制过程进行了研究，其中的系统动态载荷控制是试验台软件部分的关键问题之一。设计制造出经济实用的电模拟转鼓试验台，建立了试验台传动系统的数学模型，辨识出试验台控制系统的传递函数。通过大量的仿真计算和试验，找出最大限度提高转鼓动态响应速度的控制方法和控制参数，从而提高了电模拟转鼓试验台的模拟控制精度。