Online monitoring system and method for partial discharge of intelligent switch cabinet based on ultra-high frequency detection

Abstract

The invention discloses an online monitoring system and a method for partial discharge of an intelligent switch cabinet based on ultra-high frequency detection. The online monitoring system comprises a sensor unit, a signal conditioning unit, a MCU (Micro Control Unit) unit, a communication unit, a system power supply and an upper machine monitoring unit. The online monitoring method comprises the following steps that: the sensor unit finishes collection of partial discharge signals in the switch cabinet; the signal conditioning unit realizes amplification, filtering, frequency reduction and bias of the signals, thus obtaining signals which can be converted by an ADC (Analog to Digital Converter) module in a DSP (Digital Signal Processor); the MCU unit realizes analysis and procession of the signals; and data are uploaded to an upper machine in a monitoring room through an Ethernet. According to the online monitoring system and the method for the partial discharge of the intelligent switch cabinet based on the ultra-high frequency detection disclosed by the invention, collection and procession of high-frequency signals conducted by the DSP are realized by adopting a frequency spectrum shifting technology; a time-frequency analysis technology and a mode identification theory are applied to the monitoring system, therefore, the monitoring system is functional in fault diagnosis; and in addition, an IEC61850 standard is adopted by the system, consequently, management of various IEDs (Intelligent Electronic Devices) and interconnecting as well as networking of equipment in a transformer substation are convenient.

Description

technical field [0001] The invention relates to an on-line monitoring system for partial discharge of high-voltage power equipment and an operation and fault diagnosis method, and is especially suitable for on-line monitoring and fault diagnosis of ultra-high frequency partial discharge signals of high-voltage switch cabinets in intelligent substations. Background technique [0002] With the development of national smart grid technology, real-time status monitoring and fault diagnosis of key parts of substation main equipment have become an important indicator to measure the reliable operation of the power grid. High-voltage switchgear is an important part of intelligent substation. By developing a monitoring system suitable for partial discharge of high-voltage switchgear, real-time monitoring of local discharge and insulation performance of main equipment, mastering equipment operation, timely detection of hidden troubles, and taking measures to repair and deal with them ,...

AI Technical Summary

Problems solved by technology

Ultrasonic detection has strong anti-interference ability, and the detection frequency band is mainly concentrated in 20kHz-220kHz, while the frequency range generated by partial discharge signals is extremely wide, and high-frequency signals can reach tens of GHz. The narrow ultrasonic detection range is not conducive to the spectrum analysis of discharge signals

Furthermore, the above two detection devices are all data processed in the host computer in the monitoring room, and the discharge information cannot be displayed on the spot, which is not conducive to the inspection and maintenance of the on-site maintenance personnel.

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