Considering the complex environment in 750 kV AC substation,porcelain insulators have particular electric field and voltage distribution in comparison with those used in AC transmission line,meanwhile,the investigatio...Considering the complex environment in 750 kV AC substation,porcelain insulators have particular electric field and voltage distribution in comparison with those used in AC transmission line,meanwhile,the investigation of a typical 750 kV AC substation located in Lanzhou with ultraviolet imager(UVI) demonstrated that the corona discharge of some insulators is serious due to the improper structure design and installation,so research on porcelain insulators used in substation is needed.The three-dimensional finite element method(FEM) 750 kV AC substation calculation model was established to calculate electric field and voltage distribution of insulators,and the voltage distribution curves along insulators which are classified by type and suspension location were obtained using a novel FEM method which can effectively reduce the calculation amount without losing accuracy,meanwhile,the effect of the grading ring for improving voltage distribution of insulators was studied by adjusting the structure parameters of grading ring. Consequently,an optimization structure of rings was proposed by improving the voltage distribution of insulator string and reducing the electric strength of grading ring for the purpose of restricting corona noise,and the onsite observations by UVI showed that the newly manufactured and installed grading ring could obviously avoid the occurrences of corona discharge which validates the optimization design.This paper proposed an effective method combining UVI observation and FEM calculation to study voltage-sharing characteristics of porcelain insulators,and the results can provide experiences and references for the design of 750 kV AC substation.展开更多
750 kV substation of Riyue Mountain, Qinghai is a substation that annual average thunderstorm days are the maximum at the same volt- age level and altitude in the wodd. We detailedly described testing methods and step...750 kV substation of Riyue Mountain, Qinghai is a substation that annual average thunderstorm days are the maximum at the same volt- age level and altitude in the wodd. We detailedly described testing methods and steps of 6 characteristic parameters for grounding device of 750 kV substation by using 8000S comprehensive test system, and scientifically judged overall performance of the grounding device. Moreover, we espe- cially emphasized key and difficult points in testing process, providing reference for the majority of grounding test workers.展开更多
文摘Considering the complex environment in 750 kV AC substation,porcelain insulators have particular electric field and voltage distribution in comparison with those used in AC transmission line,meanwhile,the investigation of a typical 750 kV AC substation located in Lanzhou with ultraviolet imager(UVI) demonstrated that the corona discharge of some insulators is serious due to the improper structure design and installation,so research on porcelain insulators used in substation is needed.The three-dimensional finite element method(FEM) 750 kV AC substation calculation model was established to calculate electric field and voltage distribution of insulators,and the voltage distribution curves along insulators which are classified by type and suspension location were obtained using a novel FEM method which can effectively reduce the calculation amount without losing accuracy,meanwhile,the effect of the grading ring for improving voltage distribution of insulators was studied by adjusting the structure parameters of grading ring. Consequently,an optimization structure of rings was proposed by improving the voltage distribution of insulator string and reducing the electric strength of grading ring for the purpose of restricting corona noise,and the onsite observations by UVI showed that the newly manufactured and installed grading ring could obviously avoid the occurrences of corona discharge which validates the optimization design.This paper proposed an effective method combining UVI observation and FEM calculation to study voltage-sharing characteristics of porcelain insulators,and the results can provide experiences and references for the design of 750 kV AC substation.
文摘750 kV substation of Riyue Mountain, Qinghai is a substation that annual average thunderstorm days are the maximum at the same volt- age level and altitude in the wodd. We detailedly described testing methods and steps of 6 characteristic parameters for grounding device of 750 kV substation by using 8000S comprehensive test system, and scientifically judged overall performance of the grounding device. Moreover, we espe- cially emphasized key and difficult points in testing process, providing reference for the majority of grounding test workers.
