Abstract: A long-distance high-voltage cable fault degree detection method. A cable fault positioning curve is obtained by using a frequency-domain reflection method, and a cable fault positioning compensation curve is determined by means of theoretical calculation in combination with the parameters of a frequency-domain incident signal, cable structure parameters, and characteristic parameters of each layer of materials of the field test; furthermore, a cable fault diagnosis curve is determined on the basis of the cable fault positioning curve and the cable fault positioning compensation curve, the severity of the fault is determined by means of the amplitude of a peak point of the cable fault diagnosis curve, and the accuracy of long-distance high-voltage cable fault degree diagnosis is effectively improved.

Abstract: The present disclosure relates to the field of high-voltage AC cable insulation technologies, and provides a method for predicting insulation aging life of a high-voltage submarine cable and a device. The method includes: obtaining environmental data and cable breakdown time of a cable sample; the environmental data including an electric field, temperature, and mechanical stress applied to the cable sample by an environment; calculating characteristic breakdown time corresponding to the cable sample by Weibull distribution based on the cable breakdown time of the cable sample; determining an insulation aging life prediction model of the high-voltage submarine cable based on the environmental data and the characteristic breakdown time of the cable sample; obtaining environmental data of a cable to be predicted in an actual application environment, and calculating insulation aging life of the cable to be predicted by using the prediction model.

Abstract: A method for detecting a storage life of a pre-crosslinked material is provided. Tableting is performed on an unaged pre-crosslinked material to obtain crosslinked polyethylene. A crosslinking degree and a mechanical property of the crosslinked polyethylene are measured to obtain reference data. The pre-crosslinked material is heated to obtain a fast-aged pre-crosslinked material. The crosslinking degree and mechanical property of crosslinked polyethylene obtained from the fast-aged pre-crosslinked material are measured to obtain measurement results, which are compared with the reference data. If comparison results all fall within corresponding ranges, the time period of heating is increased by a step to repeat the above steps until the comparison results do not all fall within the corresponding ranges. A result obtained by subtracting the step from the time period of heating is converted into a time period of storage at the room temperature.