| In the low-voltage distribution network,due to the large proportion of single-phase load,the randomness of load usage is high,which often causes the three-phase load imbalance of the distribution network.With the increase of load type,load power,and the increase of non-linear load,single-phase load and impact load,the three-phase unbalance problem of low-voltage distribution network becomes more and more serious,which is safe,economical and reliable for distribution network.Operation poses a serious hazard.The long-term three-phase unbalanced operation of the low-voltage distribution network will:reduce the output of the transformer,increase the loss of the transformer,malfunction of the grid protection components,reduce the active power of the induction motor output,increase the line loss,and“low voltage” at the end of the distribution network.The most direct way to solve the problem of three-phase load imbalance in the distribution network is to directly change the electrical connection mode of the specific single-phase load,but this method has been limited by equipment cost,condition monitoring and safety.With the rise of the "Internet +" and "Internet of Things" concepts,devices such as smart leakage protectors,smart air-openers and smart commutators have gradually been connected to the power system.The subject intends to access the intelligent commutator switch at the user end,making full use of its multi-functional integration features such as phase sequence switching,data acquisition,data transceiving and wireless transmission,and directly realizes remote intelligent adjustment of the phase sequence of the single-phase load access.To achieve three-phase intelligent balance control of the distribution area and the local distribution network.The specific research contents include:Firstly,the research background and engineering application value of the subject are introduced.The solution to the three-phase imbalance problem of the distribution network and the status quo of key technologies are discussed.On this basis,the research objectives of the subject are put forward.And specific research content;secondly,from the aspects of intelligent commutator switchgear,data transmission and background service system,network security,etc.,the physical structure and operation mechanism of the system are introduced in detail;thirdly,the mathematics of distribution network based on single-phase load is established.Model,which constructs a multi-objective optimization function based on the connection state of the intelligent commutator and the current of each phase of thesystem,proposes a commutation optimization control strategy;Fourth,relying on the technical transformation project that the company will carry out,on a distribution area Carry out technical transformation and form an analog three-phase unbalanced control system through intelligent reversing equipment.This project is used as a case to analyze and demonstrate the effect and significance of the research.Fifth,combined with the above theoretical analysis and practical effects,the application of the subject The social and economic benefits are discussed.Finally,a systematic summary of the work of the subject research is carried out.Lack of presence on the project,proposed future Solutions. |
