Introduction: Arrester intelligent online monitoring system consists of an integrated monitoring unit, multiple arrester online monitoring devices and bus voltage monitoring devices. The system is mainly used for real-time monitoring of arrester working conditions. Monitoring parameters include full current, resistive current and the number of actions.
The integrated monitoring unit provides two RS485 field buses. Each field bus can be connected with 32 online monitoring devices. The online monitoring device of each surge arrester is configured with 3 sensors to simultaneously monitor the operating conditions of ABC three-phase arrester.
Integrated monitoring unit supports IEC61850 protocol and can be used in intelligent substation as an intelligent electronic device (IED).
Main technical parameters of the system
It has the following features:
1. Adopting high-precision zero-flux sensor, digital filter and multi-channel cooperative sampling technology to achieve high measurement accuracy and make the measurement error less than 1% for the resistive current of surge arrester and less than 0.5% for the capacitance and dielectric loss factor of capacitive type equipment.
2. Adopting phase-locked loop technology to automatically track the frequency of the power grid, solve the problem of spectrum leakage in Fourier transform, and prevent the measurement from the impact of fluctuations in the power grid frequency.
3. Having high anti-interference capability and adopting multi-layer shielding technology to effectively shield the interference of electric field and magnetic field and stabilize the working sites under serious electromagnetic interference.
4. Adopting multi-level lightning protection technology to suppress thunderbolts from power lines, signal lines or data lines to ensure the safety of online monitoring devices and their sensors.
5. Adopting a modular design to ensure that all online monitoring devices can use the same hardware and are easy to maintain.
6. Adopting a distributed structure to achieve high networking flexibility and not affect the system structure whether the monitoring device is increased or reduced.
7. Adopting in-situ measurement and digital transmission to completely solve the problem of distortion in the analog signal transmission.
8. Supporting IEC619850 protocol, accessing to the integrated monitoring system of intelligent substation, and serving as an independent online monitoring system of the surge arrester and capacitive type equipment.