Anti Design Of Traction Current Harmonics Of Track Circuit Based On DSP

With the development of the economy,China's railways have been rapidly improved and developed.The running speed of trains has also been improved.There are more and more electronic devices used in railway signal equipment in China.Electronic signal equipment is susceptible to interference in a strong electrical environment and the impact on the safe operation of trains is becoming more and more serious.The impact is also getting worse.As far as the signal equipment of the ZPW2000 track circuit is concerned,the harmonics of the traction current are easy to forn adjacent frequency and co-channel interference,which is the main cause of the ZPW2000 track circuit failure.It is also a hotspot and difficulty in the research of signal equipment anti-interference.In order to ensure the safety of railway transportation,measures must be taken to prevent harmonic interference and the failure of the track circuit should be avoided as much as possible to guarantee the safe operation and efficiency of the train.The research work of this paper has the following aspects mainly:Firstly,the proportion of each harmonic is determined by analyzing the interference source and consulting the data.Thereby the technical specifications of the filter,such as the working bandwidth,Q value and attenuation can be determined.Secondly,according to indicators,an active amplifier which is based on an operational amplifier and a digital filter which is based on DSP are designed and fabricated.Then according to the experimental test data,we need to list the tables and analyze the results to draw conclusions and give the performance of the active filter and the digital filter.Finally,in the DSP filter design process,in order to achieve the filtering of different harmonic frequencies,the adaptive filter is selected as the simulation filter and the adaptive filtering processing of the signal is realized by using the LMS algorithm.Based on this algorithm and DSP experiment board,the DSP filter is developed,the main program of debugging is written to realize the function of adaptive filter and the anti-interference index of the filter is verified by the result.Compared to passive filters and amplifier-based active filter,DSP filters use integrated chips to complete signal processing and have the ability to adapt to multiple frequencies,high performance indicators and more stability.