Alternative Protections on Inductance Coils

In the article the authors present the principle of operation of alternative maximum current protection (MCP) and protection against power cable earth faults. The purpose of these protections is the protection of high-voltage electrical installations, voltage 10-35kV from short circuits. These protections are performed without the use of current relays and current transformers (CTs) with metal cores widely used in the electric power industry, which have significant weight and dimensional parameters and high price cost. The proposed protection is made with the use of inductive coils, which have a number of known advantages for relay protection in comparison with CTs and other magnetosensitive elements and the possibility of their installation in the magnetic field created by the current- carrying busbar of the cell of the complete switchgear and closed switchgear. Protections with their application can be used instead of traditional current protections for various electrical installations, but at the same time by their technical and economic characteristics are not inferior to them. To expand the range of relay protection, the presented protections characterize an innovative approach in relay protection by using inductance coils. The resource-saving nature of these protections lies in the use of inductive coils, which are, both in terms of cost and weight and dimensional parameters, an order of magnitude cheaper and smaller in size and weight than the aforementioned CTs. The proposed protections are carried out in the form of structures with their installation inside the cells of complete switchgears and closed switchgears, voltage 10 and 35 kV.