【正文】 system protection basic condition is joins the entire system each main equipment protective device with the puter work, that is realization microputer protective device worked. This under the current engineering factor is pletely possible. Regarding the general non system protection, the realization protective device puter working also has the very big advantage. The relay protection equipment can obtain system failure information more, then to the breakdown nature, the breakdown position judgment and the breakdown distance examination is more accurate. Passed through the very long time to the autoadapted protection principle research, also has yielded the certain result, but must realize truly protects to the system movement way and the malfunction autoadapted, must obtain the more systems movement and the breakdown information, only then realization protection puter worked, can achieve this point. Regarding certain protective device realization puter workings, also can enhance the protection the reliability. The Tianjin University in 1993 proposed in view of the future Three Ges hydroelectric power station 500kv ultrahigh voltage multi return routes generatrix one kind of distributional generatrix protection principle, developed successfully this kind of equipment initially. Its principle is disperses the traditional central generatrix protection certain (with to protect generatrix to return way to be same) the generatrix protection unit, the dispersible attire is located in on various return routes protection screen, each protection unit joins with the puter work, each protection unit only inputs this return route the amperage, after transforms it the digital quantity, transmits through the puter work for other all return routes protection unit, each protection unit acts according to this return route the amperage and other all return routes amperage which obtains from the puter work, carries on the generatrix differential motion protection the putation, if the puted result proof is the generatrix interior breakdown then only jumps the book size return route circuit breaker, Breakdown generatrix isolation. When generatrix area breakdown, each protection unit all calculates for exterior breakdown does not act. This kind the distributional gener 9 atrix protection principle which realizes with the puter work, has the high reliability compared to the traditional central generatrix protection principle. Because if a protection unit receives the disturbance or the miscalculation when moves by mistake, only can wrongly jump the book size return route, cannot create causes the generatrix entire the malignant accident which excises, this regarding looks like the Three Ges power plant to have the ultrahigh voltage generatrix the system key position to be extremely important. By above may know, microputer protective device may enhance the protection performance and the reliability greatly, this is the microputer protection development inevitable trend. protections, control, survey, data munication integrations In realization relay protection puterizing with under the condition, the protective device is in fact a high performance, the multipurpose puter, is in an entire electrical power system puter work intelligent terminal. It may gain the electrical power system movement and breakdown any information and the data from the , also may protect the part which obtains it any information and the data transfer for the work control center or no matter what a terminal. Therefore, each microputer protective device not only may complete the relay protection function, moreover in does not have in the breakdown normal operation situation also to be possible to plete the survey, the control, the data munication function, that is realization protection, control, survey, data munication integration. At present, in order to survey, the protection and the control need, outdoor transformer substation all equipment, like the transformer, the line and so on the secondary voltage, the electric current all must use the control cable to direct to . Lays the massive control cable not only must massively invest, moreover makes the secondary circuit to be extremely plex. But if the above protection, the control, the survey, the data munication integration puter installation, will install in outdoor transformer substation by the protection device nearby, by the protection device voltage, the amperage is changed into after this installment internal circulation the digital quantity, will deliver through the puter work, then might avoid the massive control cable. If takes the work with the optical fiber the transmission medium, but also may avoid the electronmagetic interference. Now the photoelectric current mutual inductor (ota) and the photovoltage mutual inductor (otv) in the research trial stage, future inevitably obtained the application in the electrical power system. In uses ota and in the otv situation, the protective device should place is apart from ota and the otv recent place, that is should place by the protection device nearby. Ota and the otv light signal inputs after this integration installment in and transforms the electrical signal, on the one hand serves as the protection the putation judgme