Research On Application Of Series Capacitor Compensation In Distribution Network

The reactive power insufficiency and unqualified voltage are the long-standing problems in distribution network, the shunt capacitor compensation can’t solve those problems in the week distribution network. In this thesis, the research on application of series capacitor co mpensation in distribution network and the influences has been done. This thesis aimed at providing the theoretical basis for the application of series capacitor compensate in the distribution network.Firstly, the theory of series capacitor co mpensation in distribution network for reactive power compensation and voltage control has been constructed, the principles of compensation location and capacity has been introduced. Based on comparing the compensation principles and compensation effects of the shunt capacitor compensation and series capacitor co mpensation, here is the conclusion that shunt capacitor compensation is more valid than shunt capacitor compensation for distribution network voltage control.The research on suitability of series capacitor co mpensation in 35 kV and 10 kV distribution network has been done. By the analysis of series compensation for different types of load, there are the conclusions: the lower load power factor, voltage regulator series compensation effect is more obvious; the series compensation can effectively reduce the system voltage deviation and to suppress the voltage fluctuations for fluctuating loads for steady load; it can also suppress the high voltage caused by the small hydropower along the network; the series capacitor compensation applicable to the case of there are some reactive power distribution in the lo ng-distance power lines, it applicable to the case of there are some reactive power for distributed energy, at this time, the series capacitor compensation can improve system voltage when the low is voltage, it can also inhibit the high voltage when the system voltage is too high.For YY area 110 k V network in Hubei power grid, the research of series compensation application and influence for 110 kV network has been done. Analysis of the problems existing in YY network that structure is weak, the voltage deviation is large, excessive harmonic content has been done. The single point compensation and two-point series compensation are established, the simulation verified that two compensation schemes programs can effectively improve the voltage quality of 110 kV network, the effect of two-point series compensation scheme is more obvious. The series compensation have little influence on the system impedance characteristics, it will not magnify the harmonics.Finally, this thesis studied the suitability issues between series and shunt capacitor compensation. By build the function of the node voltage and series-shunt compensation capacity, the voltage characteristics when series-shunt compensation with various combinations of owed compensation, total compensation, over compensation is analyzed and the suggestion of reactive compensation configuration is been given. Based on the analysis of suitability issues for YY network, the suggestion of operation optimization is given.