TN系统杂散电流的产生机理及其危害研究

配电系统的工作电流从不期望的回路返回电源时会产生杂散电流。以常用的单电源TN—S配电系统为分析对象，从电源、线路、负载三个方面分析了电路参数不平衡产生杂散电流的机理。分析结果表明，电路中任意参数的不平衡将造成中性点电位漂移，是导致TN配电系统中产生杂散电流的根本原因，并带来电磁干扰、电化学腐蚀等一系列问题；合理地设置TN配电系统的工作接地与重复接地能够有效防止杂散电流对信息设备的干扰。而改用IT系统配电方式则可以从根本上减小甚至消除杂散电流。本文提出基于MATLAB的杂散电流电路模型，对系统杂散电流进行仿真分析，验证了理论推导。

Research on Produce Mechanism and Harm of Stray Current in TN System.

When the operating current in the power distribution system flows through unintended paths back to power, it will produce stray current. Taking the single-supply TN-S system as the target, the paper analyzes the mechanism of appearence of stray current by imbalance factors of power, line and load. The results show that any imbalance parameters of circuit will cause the neutral point potential drift that is the root cause for appearence of stray current in TN system, electromagnetic interference（EMI） , corrosion, and a series of problems. TN system grounding and repeat ground reasonably can effectively reduce the generation of stray current, while TN system instead can cut down stray current, the paper establishes the stray current circuit model through MATLAB and verifies the induced theoretical.