Research On The Model And Method Of 110kV Substation Differentiation Reactive Power Planning

With the development of economy,the electrical needs of industry and daily life are increasing greatly,which makes the distribution network expand quickly and the characteristic of reactive power voltage changed a lot.At present,the relative standards of reactive power compensation allocation in distribution network only offers an allocation ratio range of capacitive reactive power in different voltage level.Confronting the different needs of reactive power allocation in distribution network,the operation speed and effectiveness of the existing reactive power allocation standards couldn’t satisfy the engineering needs.On one hand,not considering the different needs of reactive power in the same level distribution network locating in different regions and allocating the reactive power compensation by the same standard,which shows that the reactive compensation in urban places is not enough while in rural places is too much.On the other hand,not considering the coordination of reactive power between different voltage levels network,the allocation of reactive compensation will be redundant greatly in some regions,which waste the investment.Therefore,it is of great importance to propose a differentiation reactive power allocation method.The differentiation reactive power allocation method in 110 kV substation proposed by this paper is mainly about coordinate reactive power planning method of distribution network and reactive power allocation method in 110 kV substation basing on typical models.In coordinate reactive power planning method of distribution network,the coordinate reactive power planning between different voltage level distribution networks is researched,which avoids reactive power flowing through long distance and balances the reactive power locally.This paper focuses on the differentiation reactive power allocation in 110 kV distribution network,which reflects the coordinate planning with 10 kV distribution network mainly by power factor of the main transformer.When the power factor is small,it means the reactive compensation is not enough in the lower electric network and the reactive compensation in 110 kV substation should be increased,while the power factors is high means the reactive compensation in 110 kV substation could be reduced.In reactive power allocation method in 110 kV substation basing on typical models,this paper presents that a typical network is a research unit,which includes an 110 kV network in the power supply region of a 220 kV substation.In cable distribution network and overhead line distribution network,three kinds of 110 kV distribution network are constructed,including radiation structure,chain structure and T structure.According to reactive power optimization calculation of different parameters in multiple dimensions,this paper calculates the effect of different characteristic parameters on reactive compensation allocation by control variate method.Through sensitivity analysis,the influence of characteristic parameters to reactive compensation allocation is revealed,and the advice of reactive compensation allocation is proposed.This standard advice is applied to reactive power compensation planning in 110 kV substation in F city.According to the case study,the reference reactive compensation allocation ratio calculated by the proposed method is accurate and of broad adaptability,which could determine the reactive compensation optimization allocation capacity for different 110 kV substation conveniently and accurately.The differentiation reactive power planning method could help to realize the optimization allocation of reactive resource,increase the utilization of reactive power compensation equipment and increase the utilized efficiency of the power grid investment,which is of great importance in engineering application.