An upwind finite element(FE)based algorithm to calculate the ion flow field in the vicinity of multi-circuit DC transmission lines is described.The initial value estimation and boundary condition are optimized,so deta...An upwind finite element(FE)based algorithm to calculate the ion flow field in the vicinity of multi-circuit DC transmission lines is described.The initial value estimation and boundary condition are optimized,so details of the transmission lines such as bundle conductors and ground wires can be taken into account in the simulation model.Comparison between measured and computed ground level total electrical field and ion current density shows satisfactory agreement.The ion flow field of a ±500 kV HVDC project with bipolar lines on the same tower is simulated.The total electrical field and ion current density on ground level are compared among different line arrangements.展开更多
220 k V线路是当前省网主干网架,雷击跳闸是220 k V线路跳闸的主要原因。以四川电网220 k V同塔双回沫竹一二线雷电反击四相同跳故障为分析对象,基于电磁暂态软件ATP-EMTP,对同塔双回线路反击多相同跳机理及特性进行研究。研究表明:在...220 k V线路是当前省网主干网架,雷击跳闸是220 k V线路跳闸的主要原因。以四川电网220 k V同塔双回沫竹一二线雷电反击四相同跳故障为分析对象,基于电磁暂态软件ATP-EMTP,对同塔双回线路反击多相同跳机理及特性进行研究。研究表明:在一定的杆塔结构下,杆塔接地电阻和雷击时刻导线电压初始值对多相反击耐雷水平影响显著;在接地电阻较低时,应采用非平衡绝缘加强上相绝缘水平,接地电阻较大时,应采用各相平衡绝缘;多相绝缘子两端电压相近的时刻发生雷击同跳几率较大。展开更多
With rapid growth of power demand, transmission capacity is also in urgent need of upgrading. In some cases, converting existing AC transmission lines to DC lines can Improve the transmission capacity and reduce the c...With rapid growth of power demand, transmission capacity is also in urgent need of upgrading. In some cases, converting existing AC transmission lines to DC lines can Improve the transmission capacity and reduce the construction investment. In this paper, the upstream finite element method was expanded to calculate the total electric field of same tower multi-circuit DC lines converted from double-circuit AC lines, and the validity of the algorithm was confirmed by experiments. Taking a DC line converted from a typical same tower 500 kV double-circuit AC transmission line as an example, the surface electric field and the ground total electric field in different pole conductor arrangement schemes were calculated and analyzed, and the critical height of pole conductors for DC lines in residential and non-residential area were determined. Then, the corridor width of DC and AC lines at critical height in residential and non-residential areas before and after AC-DC line transformation were compared. The results indicate that for DC lines converted from common 500 kV double-circuit AC lines, the ground total electric field can meet the requirements of corresponding standard with appropriate pole conductor arrangement schemes.展开更多
相角差是1 000 k V/500 k V同塔混压线路设计要考虑的众多因素中的一个,必须对此研究。通过建立合适的模型可以对影响相角差的因素进行分析计算。计算结果表明,系统潮流和线路长度是主要原因。在满负荷条件下,变压器的影响在5°左右...相角差是1 000 k V/500 k V同塔混压线路设计要考虑的众多因素中的一个,必须对此研究。通过建立合适的模型可以对影响相角差的因素进行分析计算。计算结果表明,系统潮流和线路长度是主要原因。在满负荷条件下,变压器的影响在5°左右,300 km线路的相角差在5°左右。特高压超高压同塔输电线路设计计算条件建议可按相角差10°考虑最大影响。展开更多
基金Project Supported by China11th Five-year National Key Technologies R&D Program(2006BAA02A20)
文摘An upwind finite element(FE)based algorithm to calculate the ion flow field in the vicinity of multi-circuit DC transmission lines is described.The initial value estimation and boundary condition are optimized,so details of the transmission lines such as bundle conductors and ground wires can be taken into account in the simulation model.Comparison between measured and computed ground level total electrical field and ion current density shows satisfactory agreement.The ion flow field of a ±500 kV HVDC project with bipolar lines on the same tower is simulated.The total electrical field and ion current density on ground level are compared among different line arrangements.
文摘220 k V线路是当前省网主干网架,雷击跳闸是220 k V线路跳闸的主要原因。以四川电网220 k V同塔双回沫竹一二线雷电反击四相同跳故障为分析对象,基于电磁暂态软件ATP-EMTP,对同塔双回线路反击多相同跳机理及特性进行研究。研究表明:在一定的杆塔结构下,杆塔接地电阻和雷击时刻导线电压初始值对多相反击耐雷水平影响显著;在接地电阻较低时,应采用非平衡绝缘加强上相绝缘水平,接地电阻较大时,应采用各相平衡绝缘;多相绝缘子两端电压相近的时刻发生雷击同跳几率较大。
文摘With rapid growth of power demand, transmission capacity is also in urgent need of upgrading. In some cases, converting existing AC transmission lines to DC lines can Improve the transmission capacity and reduce the construction investment. In this paper, the upstream finite element method was expanded to calculate the total electric field of same tower multi-circuit DC lines converted from double-circuit AC lines, and the validity of the algorithm was confirmed by experiments. Taking a DC line converted from a typical same tower 500 kV double-circuit AC transmission line as an example, the surface electric field and the ground total electric field in different pole conductor arrangement schemes were calculated and analyzed, and the critical height of pole conductors for DC lines in residential and non-residential area were determined. Then, the corridor width of DC and AC lines at critical height in residential and non-residential areas before and after AC-DC line transformation were compared. The results indicate that for DC lines converted from common 500 kV double-circuit AC lines, the ground total electric field can meet the requirements of corresponding standard with appropriate pole conductor arrangement schemes.
文摘相角差是1 000 k V/500 k V同塔混压线路设计要考虑的众多因素中的一个,必须对此研究。通过建立合适的模型可以对影响相角差的因素进行分析计算。计算结果表明,系统潮流和线路长度是主要原因。在满负荷条件下,变压器的影响在5°左右,300 km线路的相角差在5°左右。特高压超高压同塔输电线路设计计算条件建议可按相角差10°考虑最大影响。
