Research On VQC Parameter Setting Method Of Substation Based On Dynamic Reactive Power Optimization

The substation automatic Voltage Quality Control(VQC) which is an important substation integrated automation function plays a dominate role in improving the voltage quality, reducing the active network loss and ensuring the safe and economic operation of the power grid. Existing research mainly focus on the study about the control strategy of substation VQC zone diagram. The control parameter setting of the voltage and the power factor limit in the zone diagram is rarely considered. However, the setting of control parameters directly influences the action effect of substation control equipment. How to reasonable set the control parameters to avoid frequent action of the regulating devices and realize the optimization of substation voltage reactive power operation state in the whole day is the key problem to be solved in the substation VQC. Therefore, in this paper, research on VQC parameter setting method of substation based on dynamic reactive power optimization is further stuidied and explored. The main research results are as follows:(1)In the view of the existing model where the power factor’s ideal target is not proper set, the voltage and the power factor’s hard constraints do not conform to the actual, as well as the daily load curve of the hour equivalent level may lead to big error problem, a new model of dynamic reactive power optimization of substation is established. This model is based on a sampling period of 5 minutes daily load curve, considering the power factor control target which meets the superior power grid voltage level changing characteristics. The voltage and power factor’s safety constraints are changed to the voltage and power factor qualified rate in the objective function, and the influence of the control equipment action numbers on the substation voltage and reactive control effect is explored. By comparing the search capabilities of bat algorithm, genetic algorithm and particle swarm optimization, the bat algorithm is used to solve the new model, and leading and correction strategy to process the model constraints is put forward to improve the random search efficiency of the bat algorithm.(2)Existing control strategy of substation VQC zone diagram is based on real-time information to determine its control scheme, which is difficult to realize the reasonable allocation of regulating equipment’s actions in the whole day, and often have the questions of frequent action numbers or action failures. For this purpose, the VQC parameter setting method of substation based on dynamic reactive power optimization is put forward in this paper. The dynamic reactive power optimization strategy of substation and the control strategy of fifteen zone diagram are combined in this method. Firstly, the optimal solution of dynamic reactive power optimization is determined to ensure the action periods throughout the day, the adjusting volume and the adjusting numbers of each period. Then combining with the control strategy of fifteen zone diagram, the corresponding control area of action periods and the upper and lower limits of control parameters are determined. For no action periods, the assessment scope of voltage and power factor is put as the setting range, and the restriction of the control equipment’s action numbers is set to 0. So that, the actual substation VQC system based on control strategy of fifteen zone diagram can have the control effect of dynamic reactive power optimization.(3)The practical data of a 110 kV substation in a region of Guangdong is analyzed as an example to verify the availabilities of substation’s dynamic reactive power optimization and VQC parameters setting method proposed in the paper. At the same time, the proposed VQC parameters setting method is applied to the substation VQC’s actual engineering practice, and the practice results show the effectiveness of proposed method in engineering application.