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Instrument SBF Voltage Transformer Multiplier Frequency AC Withstand Voltage Test Product Overview

      The induced withstand voltage test of transformers and instrument transformers is an important test to ensure that the quality of transformers meets national standards. The longitudinal insulation induced withstand voltage test of transformer windings, including inter-turn, inter-layer, inter-section, and phase-to-phase insulation, is a key item in transformer insulation testing. Due to the special nature of longitudinal insulation testing, it is necessary to apply a multiplier frequency power supply device to increase the test voltage across winding insulation, thereby achieving the purpose of the withstand voltage test.

      This product is designed and manufactured to meet the above requirements. It has been proven by extensive user experience to be simple to operate, reliable in performance, and able to effectively meet the needs of induced withstand voltage testing for transformers and instrument transformers.

II. Working Principle of SBF Voltage Transformer Multiplier Frequency AC Withstand Voltage Tester

It consists of three single-phase transformers, and its working principle is shown in Figure 1

     The primary windings of the three single-phase transformers are connected in a star configuration, and the secondary windings are connected in an open delta. Because the voltage applied to the primary windings is relatively high, the iron core saturates, and the magnetic flux in each single-phase transformer contains both fundamental frequency components and third harmonic components. The open delta connection of the secondary windings cancels out the fundamental frequency components, thereby achieving a multiplier frequency voltage output at the open delta terminals. By connecting an external single-phase voltage regulator to the windings, the triple frequency voltage can be adjusted.

III. Technical Parameters of SBF Voltage Transformer Multiplier Frequency AC Withstand Voltage Tester