基于MM440的电动架车机双频调速同步控制

针对电动架车机作业过程中，为保证架车过程的安全，必须将各台架车机之间实际高程差控制在允许范围内的问题，基于铁道标准要求，利用西门子S7—200PLC和MM440变频器等设计了一种双频调速同步控制方式，编制PLC程序控制电动机接入电源的频率，实现电动机工作速度的切换。通过对实际同步调整过程的监控，并获得高程和速度曲线，验证双频同步控制方式的可靠性。双频控制方式消除了以往架车机停机调整方式中存在的累计惯性误差，提高了架车过程的安全性。

Interior Noise Prediction for Battery Electric Vehicle Based on SEA Model

According to interior noise characteristic of Battery Electric Vehicles （ BEV）, a prediction model for BEV interior noise was established based on statistical energy analysis （SEA） method. The model was divided into multiple different structure characteristics subsystems. The parameters including modal density and coupled factor of the model were calculated. The input powers of the model were acquired by test methods. Interior noise of BEV was predicted and analyzed based on the SEA model. The validity of the model was verified by comparing the test results with the simulating data. Applying to the design method based on sound package, interior noise was optimized and the control target for reducing interior noise was achieved.