A novel method for detecting the pantograph–catenary arc based on the arc sound characteristics

Abstract

In recent years, the speed and the current transmission density of high-speed railways are increased. As a result, the rate of the occurrence of pantograph–catenary arc also increases, which directly influences the service performance of the pantograph–catenary system. The detection and identification of the pantograph–catenary arc is of great significance for evaluating the off-line level to ensure the safe operation of the pantograph–catenary system. The currently used conventional optical arc detection method would be distorted by strong sunlight or other environmental lights in the actual operation, which would affect the accuracy of detection. On the contrary, the arc sound signal is not affected by the diurnal variation and can be easily obtained; it can also be distinguished well from other interfering sounds. In this paper, a new method that uses the arc sound is proposed to realize the effective detection of the pantograph–catenary arc. The frequency spectrum and the intensity characteristics of the pantograph–catenary arc sound are analyzed. The results show that the frequency band of the arc sound signal is wide and mainly gets distributed at 5–17 kHz. The curve of the sound waveform is drawn by calculating the short-time average energy, which is used to obtain the arc’s starting time, duration, and intensity, for calculating the off-line rate.

Study on characteristics of acoustic signals generated by different DC discharge modes

“…Since the acoustic signal is generated from air vibration, the energy of the plasma acoustic signal varies with time and differs greatly in different discharge modes. The short-time average energy E n is a common time-domain feature used to describe the change in the plasma acoustic signal, which at time n is defined as [35] E xmwn m , 1 For acoustic signals, more relevant information is usually obtained in the frequency domain. Therefore, it is necessary to discuss the spectral characteristics of plasma acoustic signals.…”

Classification of DC discharge modes based on acoustic signal

“…The extraction of suitable features is an important issue in the classification of discharge modes. Generally, to fully characterize the acoustic signal, the time-frequency diagram calculated by STFT [25,26] is used to analyze how the frequency content of a nonstationary signal changes over time. Figure 2 shows the basic steps of signal processing.…”

Research on driving force and dynamic characteristics of pantograph–catenary arc

“…figure 1, during operation, the pantograph and catenary remain in electrical contact to collect electrical energy for the train. However, due to mechanical oscillation, the pantograph strip may detach from the catenary line and PC arc appear [4], which threats to power supply of electrified railways [5][6][7]. For example, arc plasma can damage the pantograph strip and catenary line, and may get close to supporting insulators under the influence of airflow, resulting in short-circuit discharge [8,9].…”