车辆线缆瞬态电磁脉冲耦合仿真与抑制技术

瞬态电磁脉冲可通过车辆互联线缆耦合至电子系统内部，造成电子设备受扰甚至损毁，研究瞬态防护器件对电磁脉冲的抑制特性可为车辆电磁防护设计与实施提供有力支撑。本文以发动机电控系统为研究对象，考虑关键金属结构、线缆与电子设备，建立发动机电磁仿真模型，计算获取了瞬态电磁脉冲作用下线缆端口耦合干扰特性；基于电磁脉冲注入方法设计并搭建了瞬态防护器件测试平台，获取了瞬态电压抑制器与压敏电阻两类典型瞬态防护器件的响应时间、钳位电压、尖峰泄露等响应特性；在仿真与测试结果的基础上，选取一型瞬态电压抑制器应用于凸轮轴位置传感器信号线的电磁防护。研究结果表明，该型瞬态电压抑制器对线缆瞬态电磁脉冲耦合干扰抑制能力接近20 dB，置于滤波器前端可有效抑制线缆耦合干扰，保护终端设备。

Vehicle cable electromagnetic pulse coupling simulation and suppression

Transient electromagnetic pulses can be coupled to vehicle electronic system through cables, causing electronic equipment disturbance, even damage. Research on the suppression characteristics of transient protection devices on electromagnetic pulse can provide strong support for vehicle electromagnetic hardening. In this paper, we build the electromagnetic simulation model of vehicle engine by considering the key metal structure, cables and electronic equipment. Cables coupling characteristics were calculated under transient electromagnetic pulse; A test platform for transient protection devices was built, and the response characteristics of transient voltage suppress (TVS) and metal oxide varistor (MOV) were obtained, such as response time, clamping voltage, and peak voltage leakage. Based on the simulation and test results, a type of TVS was selected. This TVS is used to the signal line electromagnetic protection of camshaft position sensor. The result shows that this type of TVS has an ability of cable interference suppression close to 20 dB, and placing it in the front of filter can effectively suppress cable coupling interference and protect terminal equipment.