中文摘要：

基于有限元和有限体积法的混合方法，合理地考虑了直流电晕放电和交流电晕放电之间的相互影响，解决了交直流同塔输电线路地面电场的分布计算问题。通过小尺寸模型的实验了验证计算方法的有效性。针对一回±800kV直流输电线路和两回500kV交流输电线路同塔架设的实际情况，计算了不同运行方式下的地面电场的直流分量、交流分量和离子流密度的分布情况。计算结果表明，由于交流输电线路的电晕放电，地面电场直流分量和离子流密度会有所降低。同时，地面交、直流电场均随线路高度的升高而降低，但是工频电场的变化程度比直流电场要大。

英文摘要：

Based on finite element method（FEM）and finite volume method（FVM）, the interaction between DC corona discharge and AC corona discharge was considered reasonably and simultaneously to solve the problem of computing the distribution of ground level electric field under multi-circuit AC/DC transmission lines on the same tower. Through experiments based on small-size model the effectiveness of the proposed computation method was verified. Based on actual condition of one circuit of ~800kV DC transmission and double circuits of 500kV transmission lines on the same tower, thedistribution of DC component and AC component of ground level electric field as well as that of ion current density under different operational modes were calculated. Calculation results showed that due to AC corona discharge of AC power transmission lines, the DC component of ground surface electric field and ion current density reduced some extent. Meanwhile, ground level AC electric filed strength and ground level DC electric filed strength decreased along with the increase of the height of transmission lines, and the variation extent of power frequency electric field was more obvious than DC electric field.