Study On The Assessment Method Of Power System Voltage And Reactive Power Operation Status Under Secondary Voltage Control

With the development of power system, voltage stability problems are becomingincreasingly prominent. The grid voltage and reactive power operation state assessmentis an important means of complete controling system voltage and discovering thevoltage control weaknesses. The secondary voltage control is an important part in theclassification of modern power system voltage control. Its basic mission is dividing thegrid into several control areas based on the grid characteristics, by monitoring the pilotbus voltage of the control areas, achieving a classification of coordination. Voltage andreactive power assessment and secondary voltage control plays an important role inmaintaining voltage stability from different angles, it has gradually become animportant area of research. This paper focuses on secondary voltage control and voltageand reactive operation state assessment methods to start the study. The main work is asfollows:①Research on the existing divisional method of secondary voltage control, thepilot bus selection and secondary voltage control strategy(decentralizedcontrol/coordination control), this paper put forward the applicable conditions of theexisting partition method, and verify the control effect of decentralized/coordinatedsecondary voltage control.②This paper presents a two-phase secondary voltage control zoning methodbased on improved FCM algorithm. The first stage, make the reactive source partited bycondensation in hierarchical clustering method and determine the best number ofpartition; the second stage, based on the consideration the distance between the‘partition reactive source center’ to load node and improved FCM algorithm,partitioning the load buses. IEEE-39node system and a practical power systemsimulation results verify the correctness and rationality of the method.③This paper presents a high voltage distribution network voltage and reactivepower running condition evaluation methods. This evaluation method can evaluate theoperating status of each substation and high voltage network from the3aspects ofreactive compensation capacity configuration, voltage and reactive power controlcapabilities, and partition reasonableness. A practical high voltage distribution networkevaluated results reflects the voltage and reactive power problem. And the partitionreasonable index evaluate the three partition schemes’ partition reasonableness ofIEEE39node system, accurate to evaluate the partition problem, and verified the correctness of the indexes.