Determination of application process parameters of SDn49 and determination of the insulation structure of the bar
In 1965, Swiss ABB company developed impregnating resin of epoxy acid and drunk unsaturated polyester resin, and started the process of making VPI generator. In addition, there are EU [N Corporation, Siemens Corporation, Mitsubishi Corporation, etc. In the 1970s, the manufacture of motors in China began to explore vacuum pressure impregnation processes. In the early 1980s, Shanghai Electric Machinery Factory, Dongfang Electrical Machinery Factory and Harbin Electric Machinery Factory successively sent personnel to the United States Westinghouse Company, and Siemens and BBC learned VPI technology and introduced VPI equipment. However, because impregnated resin and less adhesive tape need to be imported from abroad, and the lack of raw materials is manufactured by itself, VPI technology has not been widely applied to the manufacture of large-scale generators. The domestic vacuum pressure impregnation technology was first applied to small-sized motor manufacturing industries, and was subsequently promoted to medium-sized motors. At present, only Jinan Power Plant uses VPI technology to manufacture 135MW turbine generators, but the raw materials used are imported from abroad. At present, the biggest impediment to the adoption of vacuum pressure impregnation (ie, VH) technology in the domestic large-scale turbine generator manufacturing industry is the localization of less tape and the localization of resins. The localization work of VPI impregnated resin has been started in the 1980s, and formula design was completed in the 1990s. However, the localization of impregnated resin only stays at the laboratory stage. The application of impregnated resin still needs to be evaluated with the aluminum rods that form the main insulation structure with the less-pectinated mica tape. This completes the complete evaluation of the domestically produced VPI-impregnated resin. .
Determination of Insulation Structure The evaluation of the complete process performance of VPI impregnated resin requires the selection of a suitable main insulation structure. At present, the main insulation of stator rods of turbogenerators in foreign countries is developing toward the thin shape. The main insulation of Siemens Westinghouse is based on the insulation thickness of the asphalt insulation era, and this thickness is used as the insulation thickness of LEVELlo. With the improvement of the main insulation structure and materials, the insulation thickness of Siemens Westinghouse is now LEVEL50. In view of the current basic conditions and actual production capacity of Shanghai Steam Conditioning Co., Ltd., we use the insulation thickness of the LEVEL printed by Siemens Westinghouse, ie, the insulation thickness at the rated voltage of 0.75 kV is 3.5. This kind of insulation thickness is competitive and has strong feasibility and practicality.
The tg8-U curve of the bar produced by the VPI process is relatively gentle. That is, as the voltage increases, Lin increases slowly. Below 10°C, there is little difference in the voltage at the different voltages, and the dielectric loss value reaches the highest at 130°C, and the toggle value at 15°C decreases. The advantage of the VPI process is that it reduces the voids inside the insulation system. In contrast, the dielectric loss of sDn49 impregnated resin, although slower with increasing voltage, is higher than the imported 5384l PU resin. Comparing with the multi-adhesive molding process, the measured cry at high temperatures shows the superiority of the vPI process. As can be seen from FIG. 4 , the normal temperature dielectric loss value and the thermal dielectric loss value of the vacuum pressure impregnation process are lower than the dielectric loss value of the multi-adhesive molding process. In addition, the dielectric loss value of the vacuum pressure impregnation process tends to be gentle, and the dielectric loss of the multiple-mold molding process is large. This is mainly due to the fact that the vacuum pressure impregnation process has good process stability (under good conditions) and the air gap in the insulation system is almost zero.
Polyoxyethylene-Polyoxypropylene Block Copolymer,Pluronic L 31 Cas No.: 9003-11-6,Polyethylene-Polypropylene Glycol L 61,Pluronic L Series
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