Lightning physics observation platform

2018-10-11 manager number of times read

3D locating system of lightning VHF radiation sources

The 3D locating system of lightning VHF radiation sources was developed by scientific researchers in our institute. The 3D locating system is composed of seven affiliated observation stations. Each station synchronously receives peak-values of the VHF electromagnetism radiation pulse signals produced by lightning discharge. The VHF receiver system has its center frequency of 270 MHz with 3 dB bandwidth of 6 MHz and the measurement dynamic range can reach up to 100 dB. The peak values are recorded in every 25 μs interval when the amplitude of a signal exceeds the threshold noise level. The time resolution of peak signal is 50 ns. The system determines the 3D location of radiation sources based on the time of arrival (TOA) technique using the time difference among the peak values from 7 stations. The system can capture the 3D evolution of lightning processes in high spatiotemporal resolution. The three-dimensional space and time structure of lightning discharge channels and the distribution of charge regions in thunder clouds can be revealed by the system.

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Lightning discharge channels obtained from the 3D locating system of lightning VHF radiation sources 

Electric Field Meter

The electric field meter CS110is manufactured by Campbell. Unlike traditional rotating vane field mills, the CS110 uses a reciprocating shutter. A stepper motor opens and then closes the reciprocating shutter by 45°during measurements. The reciprocating shutter is electrically connected to ground potential by a flexible stainless-steel strap operated below its fatigue limit, resulting in an ultra-reliable electrical ground connection. It is used lightning warning.

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Single station lightning location system

The system is composed of a flat antenna and an azimuth antenna. According to the lightning electromagnetic radiation pulse received by the flat antenna and azimuth antenna, the azimuth, elevation and strength of a return stroke are calculated. Multi-station networking can improve the measurement accuracy and detection range. Information from the system  can be used for lightning research and lightning warning.

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Lightning alarm

The lightning alarm device is developed by scientific staff of our institute. It has a detection range of about 50 kilometers. It detects the electromagnetic radiation pulse emitted by lightning return strokes and release the alarm based on the number of pulses received.It is widely used in lightning research and various departments that need lightning warning.

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High precision fast and slow antenna acquisition system

The high precision fast and slow antenna acquisition system is a lightning information acquisition system with independent intellectual property developed by scientific researchers of our institute. The system is mainly composed of high-speed data collection board, fast antenna electric field measuring instrument and slow antenna electric field measuring instrument (all of which are patented). The high-speed data acquisition card can collect data at a rate of 100Mb/s and has a storage of up to 2 seconds. The time constant of fast antenna is 2 ms and that of the slow antenna is 6 seconds. The system can collect all the physical quantities of a single stroke, with high speed and precision.

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High speed video system

The high speed video system is composed of fastcam1 high speed camera and related computer software. The high speed camera can reach up to 10000 frames per second. The system can be used to record the detailed pre-breakdown process of lightning, return stroke process, precesse between return strokes and the detailed optical process of subsequent return strokes. Data from Multi-station can be used to reconstruct the three-dimensional development structure of lightning.

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