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Typhoon disasters occur in different regions of the world every year, causing damage to the relevant facilities of the power grid, such as tower collapse, disconnection, damage to the primary equipment of the substation, and even large power outages caused by cascading failures. While security and stable operation pose threats, it will cause serious impacts and losses to society, the economy and people’s lives too. This paper reviews the research status of power system risk identification under typhoon disaster from two aspects. One is the related research of pure typhoon meteorology; while the other is the impact of typhoon meteorology on power system. At present, the research on this issue is more focused on early warning related research under typhoon disasters. In addition, although there are a lot of studies on power system risk identification at present, there is little research on power system risk identification combined with typhoon disaster scenario. Finally, the research on this issue is summarized and the future prospect is proposed.

This paper mainly studies the heat transfer characteristics of stainless steel wrapped YBCO strip in the resistance superconducting current limiter under liquid nitrogen, and provides theoretical basis for the design and manufacture of superconducting current limiter through the study and comparative analysis of its electrical and thermal properties under out-of-state state.Based on the experiment, the characteristic curve of superconducting strip itself is established. On this basis, the temperature distribution of epoxy curing coil and non-epoxy curing coil in liquid nitrogen with different heat transfer coefficients and impact current is studied. For the superconducting strip without epoxy curing, the loss of superconductivity instantly generates a large amount of heat to conduct outwards. If the coil is directly in contact with liquid nitrogen, it will produce boiling phenomenon and quickly produce a large amount of gas. For different currents, the superconducting strip will eventually reach thermal equilibrium at different temperatures. The higher the current, the higher the thermal equilibrium temperature. Through simulation analysis, the current is controlled at 5 times Ic, the superconducting strip surface is in the state of nuclear boiling, and the temperature transfer is faster. The energy efficiency of the high-temperature superconducting coil cured by epoxy can limit the heat output, the heat conduction rate decreases, the coil cooling rate is slow, and the temperature difference between the surface of epoxy-liquid nitrogen decreases, and the boiling phenomenon is restrained to some extent. In this process, the heat transfer is less, which can be approximated as an adiabatic process, but the coil's tolerance time is only about 0.15s, beyond this time, the coil temperature is too high and easy to burn. In epoxy curing coil, different epoxy layer thickness has a great impact on subsequent quench recovery time. The epoxy layer thickness increases from 0.01mm to 0.2mm, and the time rapidly increases from 0.5s to 3s. If epoxy is used for curing, if the system does not consider the recovery time, epoxy can be used as thermal buffering material, but if the heat is generated too fast to be released, and the temperature exceeds the bearing limit of epoxy and strip, the strip will be damaged.As the performance of the current superconducting strip is fragile, it is a bottleneck problem in the current limiter. In order to protect the superconducting strip, in the design and manufacture of the current limiter, the scheme without epoxy curing coil is preferred.

Resistive superconducting fault current limiter is an important application direction of superconducting materials, and is also one of the hotspots in current research. The resistance type superconducting fault current limiter has the characteristics that the resistance is close to zero in steady state operation, and the resistance suddenly jumps when the line is short circuited. Its current limiting state - steady state resistance ratio is much larger than that of conventional current limiter, and is an ideal current limiter. At present, there are two kinds of tapesused in HTS, which are the generation of Bi tape and the two generation tapes represented by YBCO. At the same time, the YBCO tape can be divided into two categories: stainless steel package and copper package. To this end, we have selected three typical kinds of tapes, which are Bi2223 (one kind of Bi tape), the YBCO tape in stainless steel package and the YBCO tape of the copper package. The simulation analysis and calculation of the application of these three kinds of tape in the resistance type superconducting current limiter are carried out, and the following can be obtained through the comparison between the economy and the feasibility. Conclusion only stainless steel YBCO tape is suitable for resistive superconducting fault current limiter. Through simulation calculation, the length requirement of tape in three cases is obtained. It can be seen clearly that the length of Bi2223 tape is obviously greater than that of YBCO tape. In YBCO tape, the length of copper package tape is obviously greater than that of stainless steel tape. At the same time, the electromagnetic heat accumulation of the tape in the liquid nitrogen environment is simulated. Given a shock current, it can be seen that the temperature rise and resistance increase of the YBCO tape in the stainless steel package is obviously greater than that of the other two.Finally, according to the current tape price, the current cost of three kinds of current limiter is analyzed. It can be seen that, in addition to the economy of the stainless steel packaging YBCO tape, the other two kinds of tapesare used for the high cost of the resistance superconducting current limiter, and the volume is too large, and it is not suitable for application.