Studies On Anti-interference Technology Of TWACS In Oilfield Electrical Network

Two Way Automatic Communication System (TWACS) on power lines can realize long distance transmission penetrating through transformers, so it is very suitable for information transmission of oilfield monitoring system. At present, the demodulation of TWACS bases on time difference method in the power system. But as for oilfield electrical network which exists serious noise interference produced by pumping electrical equipments, it cannot be applied. Based on the analysis of the principle of TWACS and transfer characteristics of oilfield electrical network, the signals have made use of complex wavelet transform way to demodulation, which had reduced noise jamming effectively; have made use of digital signal processing way to accurately calculate voltage zero-crossing moment at the same time, which had diminished the transceiver time errors. These improvements made the receiving performance of TWACS circuits has greatly enhance. Through a lot of experiments, it proved that the circuit has been able to widely adapt to the oilfield, and has reached the design objective.