EXPANDING THE CAPACITIES OF CURRENT CONVERTERS OF POWER SUPPLY SYSTEMS

Abstract

This article reviews properties of current converters in power supply systems, methods for converting primary currents into secondary output values.
Schemes for retrieving information about phase losses in asynchronous motors based on current sensors, have been also investigated. Fiber-optic current sensors, magneto-galvanic current switches based on the Hall effect, electromechanical switches, current transformers and current converters with a measuring winding were investigated in order to retrieve a primary current signal. Existing current converters were not able to use the magnetic system of an asynchronous motor when altering the primary currents, as a result - the requirements of simplicity, speed and accuracy of signal conversion were not met. When measuring and monitoring electrical quantities in the power supply system, the error of the converter signal is taken as determining no more than 0.1...0.5%. As a result of analysis and comparison, a new type of current converter has been developed that requires very high accuracy of elements and devices of electrical automation in the management and protection of electrical devices of power supply systems. To determine the phase loss in asynchronous motors, the measuring windings were placed in the groove of the stator. The choice of the number of turns 1-2 enabled normalized size (5 V) for control and protection systems