Intelligent online monitoring system for substation
① Partial discharge monitoring of main transformer
Pulse current method Minimum measurable discharge: 500pC Measuring frequency band: 40k-3MHz Pulse time resolution: 10μs
UHF method Minimum measurable discharge: 50pC Frequency range: 300MHz-1500MHz
② Casing dielectric loss and capacitance monitoring
Dielectric loss factor: 0.1%-200.0% Measurement accuracy: ±0.05% Capacitance: 10pF-2μF Measurement accuracy: ±0.5%
Bushing ground current: 500μA-500mA Measurement accuracy: ±1%
③ Iron core ground current monitoring
Ground current: 1mA-5A Measurement accuracy: <2.5%
④Top oil temperature monitoring
Temperature range: 0℃-125℃ Measurement accuracy: ±0.5℃
⑤Resistance hot spot temperature measurement: use optical fiber to directly measure the hot spot temperature, the number and location of optical fiber temperature measurement points are negotiated and determined, and the measurement uncertainty is not more than 1℃
⑥Monitoring of gas and water in oil
Use gas sensors to detect H2, CO, CH4, C2H4, C2H2, C2H6, CO2;
Use micro water sensor to detect: H2O;
Oil extraction method: forced circulation of the oil pump, timely detection, no dead zone oil sample, the sampled transformer oil returns to the transformer body, not directly discharged, and will not cause transformer oil loss. The sampled oil can represent the true condition of the oil in the transformer.
Degassing method: The degassing device is stable and reliable, and its service life meets the requirements of the equipment's life cycle management regulations.
Separation method: The oil and gas separation device meets the prerequisites of no oil consumption, no oil pollution, circulating oil extraction, and maintenance-free, to ensure that the sampling method of the monitoring system does not affect the safe operation of the main equipment.
Chromatographic column: adopts regular self-activation technology, and its service life meets the requirements of the equipment's life cycle management regulations.
Detector: The service life meets the requirements of the equipment's life cycle management regulations.
Realize the continuous monitoring and recording of the gas content in the transformer oil, with the functions of data collection, analysis and processing, and fault diagnosis.
The oil and gas monitoring inlet and outlet pipelines are connected to the flange reserved for the transformer.
The carrier gas is two bottles, one main and one standby, to ensure that the normal operation of the monitoring equipment will not be affected during the carrier gas replacement process