论文部分内容阅读
为解决输电线路绝缘子自然污秽中 CaSO4等微溶盐导致相同测量盐密下人工污秽与自然污秽试验绝缘子污耐压存在差异的问题，考虑绝缘子表面污层饱和附水量，从电导率等价角度出发，研究了人工污秽(NaCl)等值盐密与自然污秽(NaCl 和 CaSO4混合盐)等值盐密的等价性，建立了混合盐表观盐密的计算公式；结合 CaSO4饱和溶解度建立了考虑盐密、灰密、不同 CaSO4质量分数的绝缘子污耐压修正公式，并与7片XWP2—160绝缘子串污耐压试验数据进行了对比。研究结果表明：在一定的盐质量浓度下，溶液的电导率随着混合盐中 CaSO4质量分数的增大而逐渐降低，污耐压修正公式修正数据与试验数据误差在7.2%以内。研究结果可为线路绝缘子污耐压修正、外绝缘设计和运行维护提供参考。“,”ABSTRACT:Due to the presence of slightly soluble salts in natural contaminants, such as CaSO4, the pollution withstand voltage are different between artificial contaminants and natural contaminants under the same measurement equivalent salt deposit density (ESDD). In order to solve this problem, considering the influence of saturated absorption of water quantity, the equivalence between the ESDD of artificial contaminants (NaCl) and the ESDD of natural contaminants (NaCl and CaSO4) on the polluted insulators was studied from the perspective of the equivalent conductivity, and the formula for calculating the soluble contaminant density of mixed salt was also proposed. To combine with the solubility of CaSO4, the correction formula of insulator AC pollution withstand voltage was proposed, which considered the ESDD, NSDD and mass fraction of CaSO4in contaminants. The results from the correction formula were compared with the experiment data from artificial pollution test of a 7-unit double-shed XWP2-160 cap and pin porcelain insulator string. The results show that at a certain salt concentration, the conductivity of solution gradually decreases with the increase of CaSO4 mass fraction in the mixed salt. The maximum error between the calculation value using the correction formula and the experiment data is less than 7.2%. The results can be important reference for the correction of insulator AC pollution withstand voltage, external insulation design, operation and maintenance of transmission lines.