Transformer bushing insulation state on-line monitoring system

Abstract

Provided is a transformer bushing insulation state on-line monitoring system. A PT signal conditioning module is connected to PT mutual inductors and a CT signal conditioning module is connected to CT mutual inductors. Three signal output channels of the PT signal conditioning module and three signal output channels of the CT signal conditioning module are connected to six signal input channels of an AD synchronous converter respectively. The signal output channels of the PT signal conditioning module are connected to a first signal input channel of a phase-locked loop module and a signal output channel of the phase-locked loop module is connected to a clock input channel. Data bus of the AD synchronous converter is connected to data bus of a master module and data bus of SRAM respectively, a channel control interface of the master module is connected to a channel control interface of the SRAM, and a signal output channel of the master module is connected to a second signal input channel of the phase-locked loop module. According to the invention, synchronous sampling of voltage and current is realized such that fundamental voltage measurement accuracy is not affected by frequency fluctuation of a grid system.

Description

technical field [0001] The invention relates to an on-line monitoring system for the insulation of power equipment, in particular to an on-line monitoring system for the insulation state of transformer bushings. Background technique [0002] The transformer bushing bows the internal high and low voltage leads of the transformer to the outside of the oil tank. It not only serves as insulation for the leads to the ground, but also serves as a fixed lead. Therefore, the insulation characteristics of the transformer bushing are the prerequisite for ensuring its safe and reliable operation. The capacitance and dielectric loss of the transformer bushing are the main indicators to reflect the insulation state of the transformer bushing, so the monitoring of the dielectric loss and capacitance of the transformer bushing is an important means to ensure its reliable operation. [0003] There are two main methods for existing transformer bushing dielectric loss and capacitance monitor...

AI Technical Summary

Problems solved by technology

The online measurement method not only greatly reduces the workload, but also conducts long-term measurement of key data such as transformer bushing dielectric loss, which can provide data support for bushing insulation aging assessment. The accuracy of bushing monitoring has been difficult to improve due to asynchronous sampling of voltage and current and differences in the environment (temperature and humidity) of the bushing.

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