Investigation of Process of the Origin and Development of Lightning in a Thunderstorm Cloud on the Basis of Physical Simulation for the Purpose of Improving Calculation Methods for Lightning Protection of Facilities
Tech Area / Field
- MAN-MCH/Machinery and Tools/Manufacturing Technology
3 Approved without Funding
Moscow Power Engineering Institute, Russia, Moscow
- Russian Electrotechnical Institute named after V. I. Lenin / High-Voltage Research Center, Russia, Moscow reg., Istra-2\nNIIIT (Pulse Techniques), Russia, Moscow
- ONERA, France, Meudon\nUniversity of Florida, USA, FL, Gainesville
Project summaryThe aim of project - improvement of the calculated methods of object lightning protection on the basis of the data using about the process of the lightning origin and development in thunderstorm cloud received with the aid of the physical laboratory simulation. That will allow to develop more substantiated physically calculated methods of lightning protection, and also to determine the lightning protection reliability of different objects with the aid of physical simulation.
Existing organization of lightning protection as the grounded objects as the airborne vehicles does not satisfy to the demanded requirements on reliability. That is because of the existing methods as experimental as theoretical research of object lightning protection does not take into account all main real physical processes occurring during the origin and the development of lightning discharge, hi particular, the correct simulation of condition in which the leader discharge of lightning develops, namely the creation of the sufficient strong background electric field (field from the thunderstorm cloud), is of principle important for the adequate presentation and investigation of the lightning discharge development.
As the exploitation experience of ultra-high voltage transmission lines showed, the thunderstorm switching-off which are caught by the lightning break through the protection wires in connection with the insufficient lightning protection of the phase wires are the essential factor of outage of that lines. Part of the thunderstorm outage for ultra-high voltage transmission lines can amount to 90% from the total number of outages.
Theoretical and experimental works connected with the producing and using of the strong - charged aerosol formations have being carried out during long time in the laboratories of the Moscow Power Engineering Institute. On the basis of the received results the unique installation (it does not have the analogues in the world) which allows to create the physical model of the thunderstorm cloud and to obtain the spark leader discharge from them was made. That permits to fulfill for the first time in world practice the laboratory tests on lightning protection of the object models subjected to the charged cloud action and to the discharges from cloud with the imitation of thunderstorm conditions. That allows reflecting the physics of processes occurring during the thunderstorm move foil under lightning protection investigations and to cancel from the using of high cost powerful high voltage installations, hi reality, new scientific approach in the lightning protection field is created. Patent (A.S. USSR N 1370800 class H05 F3 2) on the developed installation for investigation of lightning protection was received. Investigations of the lightning protection of ultra-high voltage transmission lines and substations were made on this installation to the order of Russian Joint-Stock Company "EES of Russia ". Experimental base existing in laboratories with the enlisting of equipment of the institute-participators allows to carry out the experimental investigation on the lightning discharge physics on the modern level, hi particular, there is the electro-optical transducer with the unique characteristics which permits to research the space-time characteristics of the gas discharge development from the nanosecond to millisecond range.
Physical parameters of gas discharge are investigated by the incontact spectrum methods with resolution in time and space on relative and absolute intensities of the nitrogen bands. Indicated methods have been evaluated during the investigations of streamer development hi short gaps.
And the aerosol method of simulation is, in fact, the development of the experimental method of lightning protection determination on models on the modern scientific level. This method and installation are unique (the only things in the world) and first allowed to receive the spark leader discharge (analog of lightning) some meters length from the charged aerosol medium in the laboratory conditions. That permits to investigate the process of leader orientation in spark discharge in the laboratory conditions and to receive data which will allow to improve the lightning protection determination methods and also to carry out the determination of the object protection zones by the empirical path. All that will give the possibility to develop more physically substantiated practical recommendations for design of the lightning protection systems as the ground objects as the airborne vehicles.
Realization of project works will allow:
- to receive new data about processes of the lightning discharge development and its affection on engineering objects;
- on the basis of the received new data to analyze and improve the existing calculated methods of lightning protection;
- to develop the recommendations for lightning protection improvement of the concrete engineering objects;
- to check the developed recommendations in physical experiments on the models.
Investigations of the spark discharge from aerosol medium will allow also to receive the valuable information about thunderstorm electricity physics and about parameters of the leader spark discharge. That will make contribution to the development of the problem of electric discharge in air. In particular, there will be possibility to receive the new experimental data about the process of streamer-leader transition which is the key position for investigations of the electric strength of the long air gaps what is extremely necessary for design of new high voltage installations (high voltage electrical power engineering). Project realization will allow, in the end, to improve protection of the engineering objects from such natural phenomenon as lightning, and, in particular, to increase the reliability of the electric energy supply and the exploitation safety of the airborne vehicles.
Some publications on that scientific direction are cited below:
1. Influence of the object peculiarities situated in the protection zone of lightning conductors on the character and possibility of their affection by the lightning discharge. Vereshchagin I.P., Orlov A.V., Syssoev V.S. 23 International Conference on Lightning Protection (ICLP). Firenze (Italy)., 23-27 September 1996, v. l, p. 485-488.
2. Calculation of parameters of space charge of aerosol cloud. Makalsky L.M., Koshelev M.A., Syssoev V.S. and oth. Proc. of Int. Symp. on High Voltage Engineering, Austria, Graz., 28 August - 1 September, 1995, 2161.
3. Problems of Lightning Protection of 1150 kV Power-Transmission Lines. Antsupov K.V., Bazytkin V.V., Vereshcagin I.P. and oth. 21 st Int. Conference on Lightning Protection. Berlin, Germany, September 1992, p. 55-60.
4. To method of the aircraft lightning protection tests. Lupeiko A.V., Syssoev V.S. Elektrichestvo, 1985, N 9, p. 58-59. (In Russian).