Research On The Current Sampling And Processing System Based On DSP Chip And Optical Fibre Communication

qIn this paper, a suit of optical current transducer system based on the kernel DSP is put forward, which takes full advantage of the digitalized optical fibre transducer technique , combines with the traditional measurement technique .We have done important improvement and research in several aspects. Firstly, a suit of combined power supply scheme adopting small CT power , solar battery and Li-ion cell is designed in order to satisfy the power supply demand of sampling circuit on the high voltage side . The tailor-made small CT circuit can work in the wide range of bar current . The solar battery and Li-ion cell work well as the whole reserved power supply, which guarantees that the electronic circuit can work steadily on the high voltage side. Secondly, the high speed optical transceiver system is adopted , cooperating with the Rogowski coil and exact accuracy and low power dissipation AD7895 sampling system on the high voltage side . It realizes the high speed transmission of sampling data from high voltage side to the digital processing system on the low voltage side and isolation between the two sides as well. Finally, a DSP displaying system based on the kernel SED1335 controller is introduced , which can display the waveform , virtual value , frequency and cycle period of the sampling signal, and supply a friendly human-machine interface to users . It is proved by experiments that the whole system can work steadily , and every departmental module works well. The design goal of the system is realized ,which can satisfy the measurement demand of the bar current in alternating current system .The current transducer based on DSP and optical communication technique will have wide application prospects in the future.