Research On Voltage Coordination Control Strategy For Active Distribution Network

With the increase in power load demand and the development of new energy,many distributed power sources have been connected to the distribution network,and at the same time,a series of problems have been brought about,so the concept of active distribution network is proposed for this situation.Active distribution network can promote the consumption of distributed power supplies,so it has become one of the research hotspots in recent years.Voltage coordination control is directly related to voltage quality,and also affects power supply economy.It is the key to safe and stable operation of active distribution network.Therefore,it is of great significance to study the voltage coordination control of active distribution network.The paper focuses on the following three aspects of the active distribution network voltage coordination control strategy:1)On the basis of considering economics,we establish a single-objective mathematical model of active distribution network voltage control,and propose to use the harmony search algorithm to solve the mathematical model.By coordinating the distributed power supply and the traditional reactive power compensation device output,the voltage of the network node is within a reasonable range.Finally,the improved IEEE33 node example is used to simulate the simulation,and the validity is verified by the calculation result.2)On the basis of the single-objective mathematical model,the objective function is added to establish a multi-objective mathematical model of active distribution network voltage control,and the multi-objective harmony search algorithm is used to calculate the Pareto solution.On this basis,the related technical indicators are proposed,and the entropy weight method is used to calculate the weights.We conduct a coordinated evaluation of the Pareto solution set and the group with the highest coordination score is used as the voltage coordination control strategy.The strategy gives priority to the distributed power supply.The traditional voltage regulators and distributed power supplies work together to promote thedistributed power supply and make the system node voltages within a reasonable range.The coordination evaluation uses certain theories and calculations to avoid the empirical experience of decision makers.Finally,the IEEE33 system and the PG&E69 node system are simulated and analyzed.The establishment of the above model and evaluation is beneficial to reduce the system network loss and improve the voltage operation level.3)Considering the load type of each node,commercial load,civil load and industrial load have different load characteristics.The daily load curve of the above three load characteristics is used to process the node data to form three types of maximum load,minimum load and general load.In this way,the multi-objective mathematical model is improved according to the proportion of the load mode,and the active distribution network voltage coordination control strategy is proposed.This process avoids adjustments to the system at all times,and reduces operation.Finally,the improved IEEE33 node system is used for simulation,and the voltage control strategy is proposed.The system under the maximum load mode is used to verify the rationality of the strategy.