A New 3D Method for Reactor Core Vibration Based on Silicon Steel Lamination Rules and Application in UHV Shunt Reactors

A new three-dimensional (3D) analysis method is proposed as the existing two-dimensional (2D) method has low accuracy in analysing the vibration characteristics of oil-immersed shunt reactors, such as ultrahigh-voltage (UHV) shunt reactors. First of all, a set of 3D laminated coordinate systems was defined based on silicon steel lamination rules, in which the anisotropy of magnetic properties for laminated silicon steel in the rolling direction (RD), the transverse direction (TD), and the lamination direction (LD) were considered. Then, the mapping between laminated coordinate systems and space rectangular coordinate system was established to unify the parameters in different laminated coordinate systems. With the mapping, the anisotropy of the magnetic properties in the laminated coordinate systems was transformed into a rectangular coordinate system. Next, two sets of comparative studies between the new 3D method and the traditional 2D method were carried out, which show that the 3D method has high precision and a wide application range. Finally, the relationship between air gap number and core vibration of UHV shunt reactors was studied by the new 3D method. The results show that, as the number of air gaps increases, the magnetic flux density and the total force area of Maxwell force are increased, resulting in the intensification of core vibration. The conclusions of this paper are helpful for the design of large oil-immersed reactors.