At present, the operation and maintenance means of power grid company only include line inspection, contact temperature measurement, etc., which can not timely diagnose the operation status of cable equipment, especially for heavy load, full load and old cable equipment, which has not taken effective monitoring and detection measures, and some cables put into operation in early stage are in long-term service with faults and prone to failure, which can not guarantee reliable power supply.
Liaoning Danone uses high-frequency CT to extract signals from grounding wires and cross interconnection lines, and separates discharge pulse signals from external noise interference by means of filtering, signal feature extraction, spectrum analysis, etc., and identifies discharge types, so as to find potential defects in cables.。
Advantages of the system:
There are three high-frequency detection channels, which can receive PD signals collected from three-phase grounding wires or cross interconnection lines at the same time. The sampling frequency is 100MHz, and the bandwidth is 16khz-30mhz . Such sampling frequency and bandwidth fully meet the requirements of PD test. The synchronous input port receives the reference phase signal collected from the cable body by the synchronous coil. The communication interface communicates with the RS232 serial port of the computer through the optical fiber and photoelectric converter, transmits the data in the host computer to the computer, and then uses the expert diagnosis system to separate, classify and identify the discharge mode. The expert diagnosis system is based on a huge PD feature database, which is accumulated after analyzing and comparing a large number of PD data for a long time.
1、Real time online monitoring, real-time monitoring of partial discharge under the condition of high-voltage cable without power failure
2、ynchronous digital multi-channel partial discharge test technology can monitor multi-circuit and multi-phase cables at the same time
3、Carry out all-round monitoring of cable partial discharge, including cable body, cable intermediate joint and terminal head
4、And it can accurately locate the discharge power
5、Equipped with optical fiber communication port, long transmission distance and convenient expansion
6、Accurate positioning of local discharge power supply, with positioning accuracy of ± 3M
7、Analysis of historical data and evaluation of development trend of CAAC