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Two kinds of temperature transducers and several data process algorithms are researched in this paper in order to realize online temperature monitoring in insulation material for HV devices. And their sensibility is compared; assembler programming is also realized. The results of simulation test proved that the selected temperature transducer and data processing method has higher sensibility better stability and higher accuracy. So this device has the value of engineering application.

The measurement includes the UHF detection, conventional partial discharges (PD) measurement and the power phase analysis. The corona discharge characteristic of model GIS is researched. Then discharge level of UHF signal is estimated based on comparing of UHF detection and the conventional PD measurement.

The relationship between the morphology and the properties of aromatic polyamide 1313 (Nomex) fiber is studied systematically. Methods for increasing the crystallinity and orientation of Nomex fiber are discussed on the basis of a crystal structure model. The triclinic lattice form and the desired properties can be obtained by keeping the temperature of the heat treatment higher than that used for maximum crystallization rate and by using a higher drawing ratio. Experiments have confirmed these conclusions. The batch products have obtained the desired properties. >

In order to improve the stabilization of ferrocene, two kinds of ferrocene derivatives have been synthesized. The effects of ferrocene and its derivatives on dielectric properties of PE and XLPE (cross-linked polyethylene) are investigated in detail. The test results show that the initiation voltage of treeing and the breakdown strength of PE are enhanced by 61% and 10%, respectively, when the content of ferrocene derivative B is 1%. Using the ferrocene derivative B not only increases the treeing initiation voltage and inhibits the growth of treeing, but also increases the breakdown strength in PE and XLPE. The dielectric loss of PE and XLPE blended with ferrocene derivative B is permissible for HV plastic cable. The thermal stability of ferrocene derivative blended in PE is much better than that of ferrocene. Through measurements of the TSC (thermally stimulated current) of the samples and the relation between electric conduction and electrical stress, the mechanism of treeing inhibition by additives is investigated. >

Based on the fact that when fluoride materials are ablated by an arc they will absorb a part of the arc energy and dissociate as a result, to increase the pressure rise of SF/sub 6/ gas mixtures, two kinds of fluoride materials (PTFE, F46) were used in a SF/sub 6/ self-energy chamber, and interrupting tests were carried out. From the point of view of arc energy utilization, the influence of the fluoride materials on arc energy utilization was discussed in the range of the critical current, and utilization coefficients of arc energy were calculated with the hot gas temperature.

The organic PTCR (Positive Temperature Coefficient Resistance) material that consists of the polymer, the conductive particle and additives has been studied in this paper. The crystallinity of the polymer and the dispersivity of the conductive particle can obviously affect conducting property of the material. This property belongs to conductive characteristic of the composite dielectric, and is a kind of crystal-boundary-controlled conduction. The paper has investigated conducting property of the material, in order to gain more applications in energy saving and fire resistance.

The cross-linked polyolefine sheath material for halogen-free (HF) and low smoke (LS) flame retardant (FR) cable has been developed according to the safety and reliability requirements for important industrial facilities. On the basis of the mechanism of FR, the authors attempt to improve the effect of FR and mechanical properties. With respect to choosing the polymer system, the particle size and synergism of the FR filler and the process technology are discussed. The main properties, such as limited oxygen index (LOI 37), the tensile strength (>10 Mpa), elongation (/spl ap/160%), thermal aging, oil resistance and the processing properties can be obtained for the cross-linked polyolefine sheath material.