Power Plant Online Analytical Instrumentation, Electromagnetic Compatibility

The online analytical instruments are very important parts in the process of power plant production.. But on the one hand, with the automation of power plant increasing, many kinds of electronic equipments will be used. This will make the electromagnetic environment more complex. On the other hand, the online analytical instruments breakthrough the concept of conventional instruments and they develop in the intelligentized, network and virtual direction. These make the hardware and software designs of the instruments become more and more complex and also make the instruments more sensitive to the electromagnetic interference.The stability and accuracy are the most aspect of the instrument performance. In this regard, many foreign companies are advanced, but lots of native instruments have flaws because the native companies sometimes don't solve the electromagnetic interference problem well although the functions of their instruments are nearly the same as the foreign.Combining with the research of online motoring system of power plant, the writer studies the EMC deeply and uses many technology ways to improve the anti-electromagnetic interference performance of the instruments. The main work includes the following sides.First combining with the real project, the writer studies the sources, features and transmission ways of the electromagnetic interference. Second the writer studies the effect of the electrical fast transient / burst (EFT) to the online instruments. Third the writer also studies the anti-electromagnetic interference technology such as screen, grounding and filtering and uses these technologies in the instrument design. Fourth the writer does the EFT test and gives the solution to the problem in the test.By these researches, the thesis forms a series of theory and real technology to improve the instrument design of anti-electromagnetic interference. These theory and technology provide basis for solving problems of anti-electromagnetic interference in power plant instruments.