The purpose of this paper is to consider a constructional solution of the combined instrument transformer: constructed so that the voltage part is a column transformer, which means that the magnetic circuit of it is open and situated into a composite insulator. The aim of this research was to achieve optimal configuration of open magnetic circuit of the column voltage transformer.
The authors made analyses of electromagnetic field distribution and computed the voltage error and phase displacement for many different cases of magnetic circuits of the column voltage transformers. The analyses of the electromagnetic field distribution and computations were carried out using the 3D field‐circuit method based on the finite‐element numerical method. The results were compared with tests of a real‐life model.
The result of research is the selection of the best constructional version of the column voltage transformer; the research also gives some guidelines for design and manufacture of this construction of combined transformers.
The paper is meant for constructors of instrument transformers and presents results of research into new constructional solutions of combined transformer.
