Measurement system and method for transformer dielectric response recovery voltage

Abstract

The invention discloses a system and a method for measuring dielectric response return voltage of a transformer. An anode of a high-voltage direct-current power source (10) outputs to one end of the transformer through a first relay (11), the other end of the transformer and a cathode of the high-voltage direct-current power source are grounded, the two ends of the transformer are parallelly connected with a branch of a second relay (12) and a branch of a third relay and a measuring circuit (8), and the third relay and the measuring circuit are serially connected; the measuring circuit is composed of a breakover frequency controllable switch (2), a sampling resistor (3) and a high-value resistor (4) which are serially connected sequentially, the breakover frequency controllable switch is externally connected with a switch on-off controller (1) to control breakover frequency of the breakover frequency controllable switch, two ends of the sampling resistor outputs to a signal processing module (9), and the signal processing module comprises a voltage collecting module (5), a proportion amplifying module (6) and a computer (7) which are sequentially connected. By the system and the method, the problem of bound charge leakage in the process of measuring can be avoided, valid return voltage can be acquired by measuring, and insulation aging conditions can be accurately reflected.

Description

technical field [0001] The invention relates to a measuring system for the dielectric response recovery voltage of a transformer. The invention also relates to a method for measuring the dielectric response recovery voltage of a transformer using the system. Background technique [0002] The power transformer is the core of power transmission and distribution, and is a vital part of the power grid. Once it fails during operation, it will cause large-scale power outages and cause major economic losses. Therefore, it is necessary to ensure the safe and reliable operation of the transformer. The safe operation of a transformer largely depends on its insulation state. An accurate assessment of the oil-paper insulation state of a transformer can predict the service life of the transformer, and replace the seriously aging transformer in time to ensure the normal operation of the transformer in the power grid. The recovery voltage method is a non-destructive and effective detecti...

AI Technical Summary

Problems solved by technology

The general voltage test method (such as using a multimeter to measure), the internal resistance of the measuring circuit is small, the bound charge generated by the polarization of the oil-paper insulation system will leak quickly through the measuring circuit, it is difficult to effectively measure the recovery voltage value, and it cannot be accurate Reflect the aging condition of the insulation, so an effective recovery voltage measurement method is urgently needed

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