Abstract
The principle of operation of the developed overcurrent protection, the purpose of which is the protection of high-voltage electrical installations against short circuits, is presented. The presented protection is made without using current relays and current transformers (CTs) with ferromagnetic cores (including those built into the circuit breaker), which have significant weight and dimensions and high cost, widely used in the electric power industry. The proposed protection is made with the use of magnetically sensitive elements-hercons in the form of overcurrent protection. Protections with the use of reed switches can be used at the moment only as a duplicating protection in relation to the traditional protections of electrical installations, since there is no wide introduction into production of these protections and experience in their operation, that is, statistical data on these protections are needed. It should be said that in terms of speed such protections are not inferior to traditional ones. The presented protection characterizes an innovative approach in the implementation of relay protection and has a resource-saving effect. Resource-saving of this protection is the use of reed switches, which are both at a cost by an order of magnitude cheaper, and the weight and dimensions are much smaller in size and weight than the above-mentioned CTs. The proposed protection is performed in the form of a device with its installation inside the circuit breaker, located in a cell of a closed switchgear (ZRU) with voltage equal to 35 kV.