Transformer core clamp grounding monitoring device

Transformer core clamp grounding monitoring deviceUsed to monitor the grounding fault current of transformer iron cores and clamps, it can achieve continuous and online monitoring of the grounding current of the iron core. Through monitoring, the insulation condition of the equipment can be monitored in real time, and faults such as internal insulation moisture or damage, multi-point grounding of the iron core, foreign objects in the box, and oil sludge deposition in the oil tank can be detected in a timely manner. Early prevention and handling of accidents. More importantly, it can provide reliable data basis for the condition maintenance of such equipment.

Its working principle is:

The system uses high-precision through type sensors to convert the grounding current signal on the iron core and clamp into a voltage signal. The voltage signal enters the signal conditioning circuit, which automatically switches the range according to the voltage magnitude. Finally, it enters the signal measurement board with DSP as the processing core, which uses a high-performance 32-bit digital processing chip DSP as the core processor. The grounding current of the iron core and clamping components is accompanied by on-site interference signals, and these interference signals must be eliminated first when calculating. The traditional method is to use analog filters to remove interference signals, but analog filters are easily affected by environmental temperature and humidity, and are prone to zero drift and other phenomena over time, thus introducing new "interference". And the powerful digital computing function of DSP can use digital filtering algorithms instead of the original analog filtering algorithms. The digital filtering algorithm is not affected by environmental factors such as temperature and humidity, and has zero drift, which can solve various problems caused by analog filters. The signal measurement board calculates the grounding current of the iron core and clamping components and uploads it to the interval level monitoring IED through a digital bus. The interval layer IED adopts a unified embedded platform to implement functions such as analysis and judgment, alarm, and remote data transmission. By monitoring the magnitude of the grounding current of the iron core during operation, it is automatically determined whether the transformer iron core is not grounded or has multiple grounding points, thereby preventing the formation of floating potential and a series of faults caused by local overheating of the iron core, ensuring the safe operation of power transformers.

Adopting high-precision active zero magnetic flux sensors, intelligent selection of conditioning circuits and amplification factors based on the measured current size effectively improves measurement accuracy