关键词: 小轨道, 同频干扰, 周期性正弦波动, 红光带故障

Abstract: The conventional railway adopts ZPW-2000A track circuits with small rail included in the interlocking system. When there are interference signals with the same frequency in the circuit, the periodic sine wave of the small rail voltage occurs and long-term over-limit alarm of small rail feeding out voltage is caused in the microcomputer monitoring system. The abnormal voltage will directly lead to red light strip in section, which will affect the safety of train operation. Combining with the processing practice, this paper analyzes the causes of the same frequency interference, and puts forward the basic ideas and steps to find the same frequency interference, which is convenient for the field personnel to find and solve the problem of periodic sine wave of small rail feeding out voltage caused by the same frequency interference signal.

Key words: small rail, same frequency interference, periodic sine wave, red light strip fault