Studying the problem of increasing electric strength and decreasing dark electron currents of vacuum tube devices through conditioning of their electrodes by high-voltage nanosecond impulses

Research field: Vacuum and plasma electronics, SHF electronics

Project leader: Yurkov Nikolay Kondratievich, Doctor of Engineering Sciences, professor, head of the department ‘Radio Equipment Engineering and Production’

Key words: Vacuum tubes, conditioning process, vacuum capacitor, electrical strength, nanosecond high-voltage impulse, voltage breakdown

Abstract

Currently, researchers in Russia and abroad point out that the conditioning (training) of the electrodes in vacuum by high-voltage nanosecond impulses increases the electrical strength between them. However, the tests described in publications, were conducted on needle electrodes or electrodes with small working surface area. The tests did not find the correlation between the amplitude of conditioning nano-impulses, their number with nominal working and test voltage and dependence of dark current values. There is no data on conditioning the electrodes by different polarity impulses.

The experiments have not been performed on the combined conditioning, there is no data on the possible capacitance load value. The electrical strength of vacuum tubes and the intensity of dark electron current are most important parameters in vacuum tubes (VT) that determine both the characteristics and the reliability of operation of high-voltage high-frequency equipment - radio equipment of long-wave, medium-wave and short-wave bands, VHF radio location systems etc. The developers and engineers pay a lot of attention to the increase of electrical strength of vacuum gap and decrease of dark currents determine the importance of the suggested project. Increasing the relative parameters and reliability of high-voltage vacuum tubes is an important research problem. We think that the sources of increasing the reliability, electrical strength, decreasing the electron currents of conductivity are in the development and application of the conditioning of electrodes in vacuum by nanosecond high-voltage impulses.

Problem

Studying the problem of increasing electric strength and decreasing dark electron currents of vacuum tube devices through conditioning their electrodes by high-voltage nanosecond impulses.

Importance

Electrical strength and the intensity of dark electron currents of high-voltage VT determine their reliability of operation. The main method of increasing the electrical strength of vacuum gap with electrodes, treated according to standard procedure in VT production, is the conditioning (training) of electrode surfaces by discharges of constant, alternating or impulse current in vacuum. The team research showed the high potential of conditioning electrodes in vacuum by nanosecond high-voltage impulses to increase the electrical strength of the vacuum gap and decrease the dark electron current. Electric strength and the intensity of dark current are major parameters of vacuum capacitors, so studying the impact of conditioning with high-voltage nanosecond impulses on these parameters, developing the conditioning modes and the adequate equipment is an urgent problem the solution of which presents a research novelty.

Research Originality

Determining the interrelations between amplitudes and time period of conditioning impulses, their number, the dark currents parameters and discharge voltage in stationary and impulse modes for electrodes with big surface area and uneven electrical field in vacuum. The defined problem can be solved and the planned outcomes (increasing the electrical strength and decreasing the capacitor dark currents) can be obtained due to the fact that the research team members have wide experience in the field of developing high-voltage VT and possess some of the necessary equipment and the conditions for conducting research.

Expected outcomes and their importance

1. Increasing the electrical strength of vacuum capacitors by 15-20%.
2. Decreasing the dark electron current by 5-10 times.
3. Developing an automated station for controlling the process of conditioning.
4. Standard technological process for conditioning high-voltage vacuum capacitors with nanosecond impulses.
5. Publication of 6-7 articles in peer-reviewed journals.
6. Preparing research books on automated process of conditioning of vacuum capacitors with high-voltage nanosecond impulses.
7. Writing the thesis for the academic degree of Candidate of Engineering Sciences.

Sphere of application

Electrical strength and the intensity of dark electron currents of high-voltage VTs determine their reliability of operation. The main method of increasing the electrical strength of vacuum gap with electrodes, treated according to standard procedure in VT production is the conditioning (training) of electrode surfaces by discharges of constant, alternating or impulse current in vacuum. The team research showed the high potential of conditioning electrodes in vacuum by nanosecond high-voltage impulses to increase the electrical strength of the vacuum gap and decrease the dark electron current. Electric strength and the dark current intensity are major parameters of vacuum capacitors, so studying the impact of conditioning with high-voltage nanosecond impulses on these parameters, developing the conditioning modes and the adequate equipment is an urgent problem the solution of which presents a research novelty. The R&D project is planned to include the study of conditioning of VT with high-voltage nanosecond impulses. The research will develop the experimental databank on voltage breakdown and vacuum discharge.

Contacts

Tel.: +7 (412) 36-82-12, +7 (412) 56-43-46
E-mail: kipra@pnzgu.ru,  yurkov_nk@mail.ru

Дата создания: 10.11.2017 11:34
Дата обновления: 28.11.2017 09:29