Application of Partial Discharge Online Monitoring Technology in ± 660kV Converter Transformer
The partial discharge detection technology (UHF) is specially used in YD-B Phase of ± 660kV converter trans- former pole I system, in connection with overheating failure problems. Through analysis by PRPD map to strengthen the monitoring for partial discharge defective of converter transformer, the continuous tracking for the running state of con- verter transformer can be achieved. Application results show that: the signal of partial discharge characteristics can be ef- fectively found inside the converter transformer through UHF Online Monitoring techniques, which has good sensitivity and Interference capability, providing guarantee for safe and stable running of power equipment.
UHF Stacked Hilbert Antenna Array for Partial Discharge Detection
This communication proposed an ultra-high frequency (UHF) stacked Hilbert antenna array to broaden bandwidth and increase gain of Hilbert fractal antenna. Two parasitic curves were added to improve the third order Hilbert curve and stacked structure was applied to the new antenna element. The UHF stacked Hilbert antenna was designed as antenna array that involved 2 × 2 elements and fed by the Wilkinson's four-way power divider. Measurement results show that the UHF stacked Hilbert antenna array achieves a maximum gain of -1 dBi and exhibits a wide impedance bandwidth. Actual partial discharge (PD) experiments were carried out for typical artificial insulation defect models, while the proposed antenna array and an existing Hilbert fractal antenna were both used for PD measurements. The proposed antenna array was superior in this respect and effective for UHF online monitoring of PDs in electrical apparatus.
Watershed road network analysis with an emphasis on fire fighting management.
The aim of this study is fire hazard zoning the Chehel-Chay watershed and analysis of road network in order to fire-fighting management. Using effective factors on fire occurrence, the fire hazard ...