Design Of Variable Temperature Measurement System Of Space Charge

In high voltage direct current cables gradually exposed the problem ofspace charge in polymer, has attracted more and more attention of scholars bothdomestic and abroad, then measure the space charge system is more and morenew test methods and a new theoretical method is put forward. Test the theorysystem of space charge are increasingly mature. In the insulation aging problemmaterial, temperature is the main influencing factor, in high voltage direct currentcable, cable insulation layer and the temperature variation existed ladder, so it isnecessary to introduce the condition of temperature in the space chargemeasurement system of impact factors.This paper PEA method as the theoretical basis for structural transformationof the has mature space charge of test systems. By a transformation in the upperelectrode and the lower electrode as well as measuring system struct ure,reasonable and minimally affect other parts of the case, the introduction of thesystem architecture of the variable temperature. The heating system is heated sothat the sample on the following different temperatures produce a variabletemperature so as to achieve the purpose of the test system of variabletemperature and space charge.Test part the variable temperature test of space charge Select thepolyethylene and polypropylene as a sample, respectively in30℃,40℃and50℃under the condition of the space charge test,at electric field intensity with20kv/mm,30kv/mm and40kv/mm，compared with the same electric fieldintensity under different temperature on the influence of space charge. Test showthat PE sample injection the same polarity charge, when the temperatureincreasing that space charge is also increasing, at40kV/mm. The temperatureinfluence on the space charge distribution is most obvious, but the space chargedistribution of PP is almost not affected by temperature, temperature rise but the space charge injection is not obvious. At the same time studies the effect ofcrystal type on space charge,and the different types of polyprorylenepolymerization test of space charge. Test show that, improve the electric fieldintensity the PP space charge injection is not obvious, but copolymerizationpolypropylene in the electric field intensity of up to30k V/mm, have obviousphenomena of space charge injection, so type for the homopolymerization of PPspace charge ability stronger than the copolymerzation of PP...