ELECTRIC POWER RESEARCH INSTITUTE. CHINA SOUTHERN POWER GRID

Granulation method and device for crosslinked polyethylene cable insulating material having voltage grade of at least 500 kV are provided. The method includes: controlling melt extrusion system to melt insulating material; directing the melt into melt gear pump through first branch flow channel; measuring pressures at inlet and outlet of the melt gear pump, and calculates first pressure difference Δp 1 ; rotational speed of melt gear pump is adjusted such that Δp 1 approximates to 0; measuring pressures at inlet and outlet of capillary mold, and calculate second pressure difference Δp 2 ; volume flow rate Q of the melt flowing into capillary mold is obtained based on number of steps of rotation of melt gear pump; shear rate, shear stress and shear viscosity η of the melt are obtained based on Q and Δp 2 ; and adjusting process parameters, adjusting η to obtain adjusted η′, and causing η′ to be within processing-suitable viscosity range.

A direct-current energy-consuming apparatus, a method and a device for controlling a direct-current energy-consuming apparatus, and a storage medium are provided. The direct-current energy-consuming apparatus includes an energy-consuming resistor, a power module, an inductor and a control module. The inductor is arranged in a branch formed by the energy-consuming resistor and the power module connected in series. The control module is configured to switch off the power module when it is detected that a voltage between two ends of the direct-current energy-consuming apparatus is greater than a first voltage threshold, and switch on the power module, when it is detected that a voltage between two ends of the direct-current energy-consuming apparatus is less than a second voltage threshold, where the two voltage thresholds are determined based on a rated voltage of a corresponding direct-current power transmission system.

A method for evaluating a degassing effect of a cross-linked polyethylene cable, includes: acquiring a cable sample to be detected; heating the cable sample to be detected; under a darkroom condition, acquiring at least one light spot image of said transparent cable sample under irradiation of a monochromatic laser light source; extracting light intensity data of the at least one light spot image in a preset light spot image range; normalizing the light intensity data, and obtaining the maximum value and an average value of normalized light intensity coefficients of said transparent cable sample in a preset thickness range of the insulating layer; calculating a degassing uniformity coefficient according to the maximum value and the average value; and obtaining an evaluation result of the degassing effect of the cross-linked polyethylene cable according to the maximum value, the average value, and the degassing uniformity coefficient.

A temperature measurement method for submarine cable factory joints and a device therefor are provided. The method includes: obtaining (S201) measured temperature values of respective reference key areas of a reference submarine cable factory joint, a main body structure of the reference submarine cable factory joint being the same as that of a target submarine cable factory joint, environment where the reference submarine cable factory joint is located is the same as environment where the target submarine cable factory joint is located, and the reference submarine cable factory joint and the target submarine cable factory joint are spaced apart from each other by a preset distance and then placed side by side; and determining (S202) the measured temperature values of respective reference key areas as measured temperature values of corresponding measurement key areas of the target submarine cable factory joint.

A method includes: step 1: determining initial elements of the formulation, including types of a base resin, an antioxidant, and a crosslinking agent; step 2: testing a sample prepared by hot press molding the pure base resin, and obtaining an optimized base resin sequentially through qualitative evaluation indicator I and quantitative evaluation indicator I; step 3: preparing multiple groups of crosslinking agent/antioxidant/base resin blends, and obtaining an optimized crosslinking agent formulation sequentially through qualitative evaluation indicator II and quantitative evaluation indicator II; step 4: preparing multiple groups of crosslinking agent/antioxidant/base resin blends, and obtaining an optimized antioxidant formulation sequentially through qualitative evaluation indicator III and quantitative evaluation indicator III; and step 5: verifying through electrical properties, if parameter measurement results all meet requirements, the formulation of the material is considered as an optimized formulation, and if not, returning to test a next candidate to be tested.

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.

Granulation method and device for crosslinked polyethylene cable insulating material having voltage grade of at least 500 kV are provided. The method includes: controlling melt extrusion system to melt insulating material; directing the melt into melt gear pump through first branch flow channel; measuring pressures at inlet and outlet of the melt gear pump, and calculates first pressure difference Δp 1 ; rotational speed of melt gear pump is adjusted such that Δp 1 approximates to 0; measuring pressures at inlet and outlet of capillary mold, and calculate second pressure difference Δp 2 ; volume flow rate Q of the melt flowing into capillary mold is obtained based on number of steps of rotation of melt gear pump; shear rate, shear stress and shear viscosity η of the melt are obtained based on Q and Δp 2 ; and adjusting process parameters, adjusting η to obtain adjusted η′, and causing η′ to be within processing-suitable viscosity range.

A silicone rubber insulator shed material, and a silicone rubber insulator and a preparation method therefor and an application thereof. The components of the silicone rubber insulator shed material comprise silicone rubber, iron oxide, nano-montmorillonite, fumed silica, aluminum hydroxide, a silane coupling agent, a vulcanizing agent, and hydroxy silicone oil, wherein the iron oxide and the nano-montmorillonite can slow down the thermal oxidation decomposition of the silicone rubber, thus improving the hydrophobicity, hydrophobic mobility and hydrophobic recovery of the silicone rubber composite insulator, thereby solving the technical problem in the prior art that the aging decomposition resistance of silicone rubber needs to be improved.

An electromagnetic transient modeling method and system for a high-efficiency synchronous machine, and, a device. The method comprises: predicting, of a synchronous machine, a first rotor angular velocity, a first rotor angle, and a first current q component of and a first current d component of an armature current, establishing a first Norton circuit for simulating the synchronous machine, and solving at the same time a second Norton circuit after equivalent transformation and a network conductance matrix so as to obtain a three-phase voltage of a synchronous machine port; according to the three-phase voltage, obtaining a second current q component, a second current d component, a second rotor angular velocity and a second rotor angle; and by means of error-controlled iterative solving, determining an electromagnetic transient simulation calculation result of the synchronous machine.

A saturation effect-based synchronous machine electromagnetic transient modeling method, system and device. In the method, by predicting a first rotor angular velocity, a first rotor angle, a first current q component, a first current d component, a first flux linkage turning point d component, a first flux linkage turning point q component and flux linkage turning data of a synchronous machine, analysis processing is performed to obtain a corresponding second current q component, second current d component, second rotor angular velocity, second rotor angle, stator flux linkage d component and stator flux linkage q component.