Stand-alone power supplies for relay protection

Abstract

At present, telemetry and relay protection devices, which are located directly on the protected element of the electric power
system or inside it, are increasingly used in the electric power industry. To supply them requires an autonomous source of low power, which has a stabilized DC voltage. Existing devices are unreliable, expensive to manufacture and operate. In contrast to the well-known power supply devices, it is proposed to use Autonomous power sources to provide constant current for relay protection and diagnostics devices, which receive energy directly from the network by means of current or voltage transformers, as well as by means of an induction Converter located in the end zone of the electric machine. To implement this, the schemes of power supply and calculation of the parameters of Autonomous power sources have been designed.