The On-Line Measuring System For Catenary-Pantograph Vibration As Well As Signal Processing Of Vibration

Catenary-pantograph vibration state is a key indicator to evaluate the relationship between catenary and pantograph. Vibration acceleration parameters can react the vibration fault of the catenary-pantograph, such as hard-point, impact etc.. When the electric locomotive runs in a high-speed, catenary-pantograph will vibrate result from structural fault of the wire. Impact in the horizontal direction and hard-point in the vertical direction will formed in the catenary-pantograph.The high-voltage end of the detection system is in a high-voltage environment, electromagnetic interference in which generated by the discontinuity of electrical arc and electric forms a grim challenge to the system.In this paper, catenary-pantograph vibration acceleration detection system is designed aimed at changing the present conditions. Two types of acceleration sensor with different principles are chosen and improved according to the environment on the spot. Signal collection and filtering pretreatment are completed in a better way by using high-speed ADC and lead a sample technique, which also lowers design difficulty and enhances Signal-to-Noise. In this paper, DSP technique which has been used in many areas is introduced into the detection of catenary-pantograph to advance the system in real-time and reduce power consumption.In order to isolate analog and collection circuit, photocoupling isolation technique is used. Acceleration signals must be transferred from the high-voltage end to the low- voltage end, transferring by cable is a effective way. In the end, signals are processed by modern data signal processing technique based on computer platform, including short-time Fourier transform, wavelet analysis etc.. Trough signal analysis, it is discovered that the application of piezoelectricity acceleration sensor and capacitance acceleration sensor together with data signal processing method realize real-time on-line detection of catenary-pantograph vibration acceleration, overcoming interference from the high-voltage end effectively.