A new approach to 110kV HV distribution grid voltage control based on coupling numerical analysis

To avoid 110kV distribution network bus voltage conducting above the over-limit during holidays especially in the Spring Festival, a new voltage regulation method based on electric coupling degree is introduced. The strategy takes example by circuit breaks in practical operation and accordingly alters key backup lines´ connection modes under the restraint of line thermal stability, transformer capacity and switching power flow on boundary when traditional voltage regulation measures are used up to obtain the optimized voltage. It proves the typical heterogeneous scale-free network features of power grid and uses electric coupling degree to identify the key substations which own the closest connections with other buses in the network, according to the results, changing corresponding backup lines from hot-spare into cold standby mode. Compared with circuit break depend on experiences in actual production, the proposed method has obvious advantage of improving the net-wide voltage with the least cut of backup lines, which is physical well-defined and convenient. The simulation results of practical grid validate the proposed strategy and show the effectiveness of optimizing the net-wide voltage profile which possess of good application prospects.