| Along with the development of the power system, power system voltage level and improvement of electrical equipment automation, especially power system relay protection technology to the integration of computer, network, intelligence and communication in the direction of development, the digital transformer output requirements, how to realize the digital analog in situ transmission of transformer, and there is no capacity problem, at the same time, according to different substation, adjust measures to local conditions, select the optimal configuration of the transformer and to seek optimal solution, is a focus in the study of this article, for cost savings, improve the economic benefit has great realistic significance. To meet the needs of the development of intelligent substation, solve the problem of electronic instrument transformer application in transformer substation, the transformer substation digitization development will certainly play a positive role.Because of its inherent magnetic saturation phenomenon of traditional electromagnetic current transformer, analyzes the problems existing in the application in protection. And introduced the application of electronic transformer characteristics and their influence on protection.This chapter puts forward 220 k V yongding river transformer substation engineering application solutions; total station with conventional transformer, through the "conventional transformer + merging unit" pattern implementation on the digital sampling. Discusses the selection of the transformer, such as installation, merge unit configuration scheme, and focusing on "conventional transformer + merging unit" is applied to implement digital sampling and in situ was carried out on the conventional transformer "reduced set of reduced capacity" and the implementation of the grounding scheme has carried on the analysis discussion; Incorporating "conventional transformer + merging unit" model is applied to the transformer substation, reduce the number of secondary winding of secondary side, reducing the height of the transformer, reduced volume, thus reduce the substation area, the economic benefit is remarkable.The application of new type of electronic transformer can overcome the hidden trouble existing in the traditional transformer, and for the future development of smart substation has significant practical reference significance. Combined with an engineering example, this paper put forwards the arrangement of electronic transformer shall comply with the following principles: saving the land occupied by the substation; electronic equipment should be placed on the side of the earth potential. Merging unit should be installed in the interior. Put forwards a new type connection scheme of main transformer neutral point equipment, solves the power supply problems of active type electronic transformer. This article analyses the influence on relay protection when the electronic transformer is in a digital saturated state, put forwards the corresponding countermeasures. |
