Electrical Cable Insulation Material
Compatibility of electrical Cable insulation material
Manufacturability of electrical Cable insulation material
About DL-500 electrical Cable insulation material
1. Achieve the transition from heavy oil filling to low density filling
Traditional oil-filled capacitors, because of the large amount of flammable insulating oil (transformer oil or alkyl benzene oil) filled with several hundred kilograms to several thousand kilograms between the large tank case and the unit capacitor, the product is easy to leak oil, fault conditions Under flammable and explosive, polluting the environment, heavy weight, and to refuel, change oil, maintenance work is relatively cumbersome. The density of insulating oil is about 0.93g/ml, while the density of this product is only about 0.5g/ml, which greatly reduces the density of electrical equipment.
2. Environment-friendly recyclable
The DL-500, developed with micro-foam technology, appears as a soft powder structure, so it only needs to be cleaned with a general cleaning cloth without using a specific solvent for cleaning. This unique feature makes it possible to reduce the air pollution caused by the evaporation of solvents during use, thereby protecting the environment. In addition, such products do not need to be replaced as often as insulating oils, which increases work efficiency and reduces labor costs. Even the replaced product can be recycled using simple processing.
3. Excellent thixotropic performance, cold filling, simple process
The DL-500, developed with micro-foam technology, is a thermoplastic double-layered microsphere material that is carefully manufactured based on fluids with thixotropy and long-term thermal stability, facilitating full filling. It has excellent thixotropic properties at room temperature and can solve external forces such as bending, vibration, and impact during production, transportation, and flow, cushioning stress, and can be filled and maintained more efficiently and simply. The product maintains a soft state at low temperatures, so not only can be filled directly at room temperature using a filling device, but also can be adjusted to meet process requirements, depending on the requirements of the filling conditions. The low-density thixotropic recyclable filler paste developed by micro-foam technology is an insulating colloid that forms a network structure through physical cross-linking. The colloid does not flow at rest and is highly hydrophobic, and can be a transformer. , Cables and other electrical equipment provide good sealing and waterproof performance, and at the same time have excellent high and low temperature performance, and under the action of shear force, the network structure is destroyed, the viscosity is greatly reduced, becomes a flowable fluid, and once the shearing force is removed, Immediately restore the original network structure.
4. Excellent electrical insulation properties
Because the selected raw materials all have good electrical insulation, the product has excellent electrical insulation properties, the volume resistivity at room temperature can reach 1015, and the breakdown voltage can reach as high as 59KV. It can be widely used for the preparation of insulation filled composites for high voltage, ultra-high voltage transformers, cables and other electrical equipment.
In short, the DL-500 developed with micro-foam technology has superior electrical properties, meets the concept of safety, environmental protection and less oil, plus its unique advantages of energy-saving, simple process, easy use, clean and pollution-free, and thus in the current transformer In the filling of cables, cables and other electrical equipment, it gradually replaces traditional fillers and is increasingly used.
University of Southampton Develops New Optical Fiber: Breaking the Temperature Dilemma Caused by Time of light
A research team at the Optoelectronics Research Center at the University of Southampton has produced a fiber, according to them, in which the propagation time of light does not change with temperature (Optica, doi: 10.13664 / OPTICA.4.000659). The team used an ingenious design to increase the group velocity of the light in the fiber by precisely eliminating the elongation of the fiber at high temperatures and the change in the fiber's thermally induced refractive index. The results verified that this is an optical fiber with a thermal delay coefficient (TCD) equal to zero, which has potential advantages in applications where the time signal in the fiber is required to be very accurate, such as metering and other applications.
Using hollow photonic bandgap designs to balance the temperature-dependent refractive index changes with temperature-induced changes in refractive index (hence, in the group velocity of light), researchers at the University of Southampton have produced an optical fiber in which the propagation time of light is not affected by the optical fiber. The effect of temperature. Image courtesy of Gregory Jasion, University of Southampton
Change from glass material to air medium
For each 1°C temperature change, the propagation time of the optical signal through a one-km standard solid core fiber varies by approximately 40ps. In some areas, such as sensing applications, this temperature sensitivity in optical fiber is a practical feature rather than a defect. However, it cannot avoid the possibility of other applications that rely on precise time signals, such as the connection of optical clock networks across the continents, the manufacture of synchronous robots for the Internet of Things industry, and the use of fiber delay circuits to stabilize precision lasers that are resistant to low-frequency noise.
Fiber optic researchers have studied many methods to reduce the temperature sensitivity of fiber propagation time. One method is to coat the fiber with a special coating to help offset the change in its refractive index with temperature. According to new research, the best result is that the standard telecom fiber's thermal sensitivity can be reduced to 3.7 ps/km. /K.
The same Southampton research team responsible for the new "Optica" study pointed out another approach, replacing the solid silica glass fiber with a hollow photonic bandgap fiber design in which most of the light power passes through the air medium rather than the glass material. Since sensitivity of about 95% of the fiber propagation time to the thermo-optic effect of silicon dioxide varies with temperature, it is reported that this change can reduce the propagation time sensitivity to 2 ps/km/K.
Thermal effect compensation
In order to reduce the sensitivity from 2 ps/km/K to zero above, the Southampton R&D team learned in detail about the parameters that determine the propagation time of light in the fiber. One of the parameters is of course the physical length of the fibre, which increases with temperature. Another parameter is the group velocity index, ng. Moreover, the team's research results show that the correct combination of fiber characteristics can be used to reduce the temperature, thus offsetting the increase in propagation time due to the thermally induced elongation of the fiber. (This is because the reduction of ng causes the light to travel faster in the fiber, the others are the same.)
After analyzing and numerically simulating the details of various coated and uncoated fiber designs, Southampton scientists, led by OSA member Eric Numkam Fokoua, produced a 2.8-m long seven-core hollow photonic bandgap fiber sample. It is 96.5% and can work in the telecommunications spectral region of about 1.55 μm. They then tested the fiber at four temperature settings from 29°C to 82°C. As predicted in the simulation analysis, the TCD measurement value of the fiber is zero, which means that the propagation time is completely insensitive to temperature changes—this is the first time we have known this to achieve this result.
Researchers suggest that these very low or even near zero transfer time thermal sensitivities should significantly improve the transmission of optical signals with precise frequency and timing in optical fibers. They believe that this result represents "a final fiber solution for time-sensitive applications."