Scientific paper ID 875 : 2013/3

At the present stage of development of Russian Railways the management rather accurately set the purpose which result is application on an electric stock of asyn-chronous electric traction motors instead of collector electric traction motors. Draft force regulation of the asynchronous traction motors is carried out by change of frequency of con-sumed current. As a result harmonics of traction current can get to the track circuit in rather wide range of frequencies.

Now compatibility of perspective electric stock and track circuits is reached by pres-entation of rigid ments to the asynchronous drive. But this approach not always yields effective result. For increase of reliability of the track circuits and the asynchronous electric traction stock the problem of design of essentially new track circuit with improved interference immunity was set.

Such track circuit was created. Creation of new audio frequency track circuit with au-tomatic control of signal level (AFTC-AC) became possible thanks to modern microprocessor base. Interference immunity of AFTC-AC is exceeded interference immunity of existing track circuits by 50 times, and its efficiency is provided even in case level of the concentrated inter-ference in a working frequency band by 10 - 20 times exceeds the minimum settlement level of a useful signal.

In addition, a number of the new operational characteristics, allowing to speak about economic efficiency of AFTC-AC was reached.