Gas Discharge Tube Research Articles

Plasma antenna with frequency adjustment

A discharge of limited length (“plasma column”) in a gas-discharge tube filled with a rarefied gas was studied. The discharge is created due to the one-sided excitation of an extended high-frequency discharge supported by a propagating azimuthally symmetric mode of the surface wave. It is shown that a “plasma column” can be an effective plasma antenna at operating frequencies below the plasma frequency (ωp), with frequency tuning due to changes in the length of the “plasma column”.

Multiple parameters control of square superlattice plasma photonic crystal

We present a novel square superlattice plasma photonic crystal (PPC) fabricated by periodic arrangement of different-sized gas discharge tubes and Al2O3 dielectric rods. The effects of the plasma, the number and location of Al2O3 rods, and the angular orientation of PPCs on the microwave transmission characteristics have been demonstrated. For the simple square lattice, a PBGa in the range of 13.40–14.20 GHz is obtained. For the square superlattice, an additional PBGb in the range of 14.35–15.10 GHz develops. While PBGa and PBGb are primarily dependent on the square sublattices of plasma rods and Al2O3 rods, respectively, a synergistic effect arising from the interplay between these two sublattices is suggested. Moreover, a new PBGc is achieved by changing the rotation angle of the PPC to 45° The multiple parameters control of square superlattice PPC may inspire new strategies for designing fully bandgap-tunable PCs and may find potential applications in various fields.

A highly efficient self-powered variable impendence system

As an efficient mechanical energy harvester, the triboelectric-electromagnetic hybrid generator (TEHG) stands as a cornerstone in self-powered systems. Nevertheless, significant impedance disparities between triboelectric nanogenerators (TENGs) and electromagnetic generators (EMGs) often hamper systems’ energy utilization efficiency, attributed to impedance mismatch at the load. Here, a variable impedance strategy is proposed, aimed at maximizing the utilization of mechanical energies converted by TEHG. This approach capitalizes on electronic components with dynamic impedance from GΩ to kΩ in response to OFF-ON state transitions, thus matching the impedance of TENG and EMG. Experimentally, an ultraviolent gas discharge tube (UV-GDT) is integrated into the self-powered variable impedance system. Operated at 240 rpm, the TEHG-driven UV-GDT extracts energy amounting to 1304.27 mJ with an 87.5 % utilization efficiency. These metrics outperform the situation where UV-GDT is individually powered by either EMG (0 mJ, 0 %) or TENG (18.24 mJ, 60.7 %). Furthermore, the mechanical energy-activated UV system demonstrates promise for sterilization, curing, and photo-chemical reactions. This variable impedance strategy resolves the impendence mismatch between TEHG and load, more importantly, provides a valuable guideline for developing hybrid generator systems with enhanced energy utilization efficiency.

A Compact-Sized Fully Self-Powered Wireless Flowmeter Based on Triboelectric Discharge.

Flow sensing exhibits significant potential for monitoring, controlling, and optimizing processes in industries, resource management, and environmental protection. However, achieving wireless real-time and omnidirectional sensing of gas/liquid flow on a simple, self-contained device without external power support has remained a formidable challenge. In this study, a compact-sized, fully self-powered wireless sensing flowmeter (CSWF) is introduced with a small size diameter of down to less than 50mm, which can transmit real-time and omnidirectional wireless signals, as driven by a rotating triboelectric nanogenerator (R-TENG). The R-TENG triggers the breakdown discharge of a gas discharge tube (GDT), which enables flow rate wireless sensing through emitted electromagnetic waves. Importantly, the performance of the CSWF is not affected by the R-TENG's varied output, while the transmission distance is greater than 10m. Real-time wireless remote monitoring of wind speed and water flow rate is successfully demonstrated. This research introduces an approach to achieve a wireless, self-powered environmental monitoring system with a diverse range of potential applications, including prolonged meteorological observations, marine environment monitoring, early warning systems for natural disasters, and remote ecosystem monitoring.

Evaluating the Performance of UV Disinfection across the 222-365 nm Spectrum against Aerosolized Bacteria and Viruses.

Bioaerosols play a significant role in the transmission of many infectious diseases, especially in enclosed indoor environments. Ultraviolet (UV) disinfection has demonstrated a high efficacy in inactivating microorganisms suspended in the air. To develop more effective and efficient UV disinfection protocols, it is necessary to evaluate and optimize the effectiveness of UV disinfection against aerosolized bacteria and viruses across the entire UV spectrum. In this study, we evaluated the performance of UV disinfection across the UV spectrum, ranging from 222 to 365 nm, against aerosolized bacteria and viruses, including Escherichia coli, Staphylococcus epidermidis, Salmonella enterica, MS2, P22, and Phi6. Six commonly available UV sources, including gas discharge tubes and light-emitting diodes with different emission spectra, were utilized, and their performance in terms of inactivation efficacy, action spectrum, and energy efficiency was determined. Among these UV sources, the krypton chloride excilamp emitting at a peak wavelength of 222 nm was the most efficient in inactivating viral bioaerosols. A low-pressure mercury lamp emitting at 254 nm performed well on both inactivation efficacy and energy efficiency. A UV light-emitting diode emitting at 268 nm demonstrated the highest bacterial inactivation efficacy, but required approximately 10 times more energy to achieve an equivalent inactivation level compared with that of the krypton chloride excilamp and low-pressure mercury lamp. This study provides insights into UV inactivation on bioaerosols, which can guide the development of effective wavelength-targeted UV air disinfection technologies and may significantly help reduce bioaerosol transmission in public areas.

Simulation of lighting characteristics of pulse discharge in cesium vapor

Mathematical modeling of characteristics of intense light source on the basis of high pressure pulse discharge in cesium vapor is performed. The investigated discharge is realized in a long ceramic tube from Al2O3 with an internal diameter of 5 mm. The amount of cesium in the discharge is determined by the value of the saturation pressure at the cold end of the tube. A current pulse with amplitude of 40 A to 250 A is periodically passed through the discharge plasma, with a frequency of 400- 1700 Hz. In the work, a mathematical model based on the equations of radiation gas dynamics is used to simulate discharge. When calculating heat exchange by radiation in plasma and light characteristics of discharge, direct integration of the radiation transfer equation is performed. The model takes into account two mechanisms for heating the walls of the gas discharge tube. Firstly, it is the molecular thermal conductivity of the near wall plasma and secondly, it is the absorption of discharge plasma radiation by walls. As a result of the simulation, the dependencies of plasma pressure and temperature, luminous flux and luminous efficacy of the discharge on the temperature of the cold tube end were investigated for different values of amplitudes of current pulses. It is shown that at all current amplitudes there is a pronounced maximum of luminous efficacy. In all studied modes of discharge combustion color rendering index exceeds Ra > 95. It is shown in particular that if the power embedded per unit of discharge length increases to 400 W/cm, the luminous flux reaches 36000 lm/cm.

A Self‐Powered Power Management Circuit for Triboelectric Nanogenerators Utilizing Gas Discharge Tube

AbstractSpark discharge is essential for extracting energy from triboelectric nanogenerators (TENGs). However, the lack of universal technical standards for most discharge switches limits their widespread application. Herein, a buck circuit utilizing gas discharge tube (GDT) as discharge switches is presented. The GDT switch significantly enhances the instantaneous power to 30 mW, 15 times higher than the direct method. When VGDT (the breakdown voltage of GDT) ≤1000 V, it can be integrated with an LC converter, forming the GDTx‐Buck circuit with a maximum energy conversion efficiency of 92.2%. When VGDT >1000 V, GDT can combine with a transformer, forming the GDT‐nT circuit, which enables higher voltage power management. The results demonstrate GDT's universal applicability, reducing circuit complexity during design. In practical applications, the circuit can illuminate 1250 LEDs at an ultra‐low operating frequency of 0.6 Hz, generating electromagnetic waves during GDT breakover, which proves valuable for self‐powered wireless applications. Additionally, the circuit drives parallel calculators and thermometers at 2 Hz in micro‐nano energy applications and provides continuous power to high‐power fire sensors. Its high integration and simple design render it highly promising for large‐scale energy management applications based on TENGs.

Tensegrity triboelectric nanogenerator for broadband blue energy harvesting in all-sea areas

The integration of high-density friction layer units is a promising approach for achieving high output in triboelectric nanogenerators (TENGs). Yet, the synchronization and sufficient contact separation of these high-density layer units are inherently challenging due to the cumulative impact of gravity. Herein, a tensegrity structure was applied and effectively organized the high-density stacked TENG units into an ordered whole, thereby proposing the T-TENG. Along with achieving orderly contact and separation of high-density friction layers, the T-TENG effectively reduced the device's height (up to 52%) and improved the friction layer surface area density (up to 1.07 cm−1). Significantly, the built-in prestress modulation not only enhances the device's load-bearing capacity but also enables ease in changing the T-TENG's response frequency by adjusting the prestress value. This is especially suitable for efficiently capturing omnidirectional wave energy in all-sea areas with frequency variations. The working mechanism and output influencing parameters of T-TENG were systematically expounded, and it demonstrated a maximum output voltage of up to 1020 V and output charge per unit time of 0.816 mC/min, sufficient to light up to 1512 LEDs directly. Moreover, customization of low-loss gas discharge tubes to amplify outputs allows T-TENG to harvest wave energy for power supply to small electronic devices such as water quality testing pens and Bluetooth modules when placed over water bodies. This work provides a foundational model to develop high-density friction layers and high-output TENGs.

A multilayer triboelectric-electromagnetic hybrid nanogenerator for vibration energy harvesting and frequency monitoring

With the advancement of sensor networks, the exploration of distributed vibrational energy resources bears significant implications. We introduce a multilayer triboelectric-electromagnetic hybrid generator (M-TEHG). The M-TEHG exhibits remarkable output capabilities across a broad frequency spectrum, with a peak power density of 2.8 W/m3 at 10 Hz. Moreover, by incorporating the gas discharge tube (GDT) as a rapid switch in the BUCK circuit, the M-TEHG provides a continuous and stable power supply for the load. This innovation not only enhances the charging rate of the M-TEHG's capacitor by 43.84–57.66%, but also enables uninterrupted power supply to temperature and humidity sensors. Additionally, the M-TEHG also possesses the capability to monitor vibration frequencies. It utilizes a linear bearing and smooth guide rod structure, effectively mitigating the impact of vibration signals from different angles. The frequency monitoring of the M-TEHG achieves an accuracy of up to 99.1% and demonstrates exceptional linearity. The integrated electricity generation and sensing capability of M-TEHG demonstrate its immense potential in various fields, such as distributed sensor networks, unmanned environment monitoring, and especially early warning systems for bridge vibration.

Research on printed circuit board external open-circuit failure gas discharge tube under short-circuit failure

Research on printed circuit board external open-circuit failure gas discharge tube under short-circuit failure

An Experimental Study on Novel Gas Discharge Tubes With Graphene as Electron Emission Material

Electrical equipment is subjected to gas discharge tube (GDT) direct current (dc) breakdown voltage dispersion and breakdown voltage drop after a surge. It is noteworthy that GDT damage may even cause the failure of electrical equipment. Accordingly, the chemical vapor deposition (CVD) of graphene was proposed in this study as an electron emission material of the GDT based on the existing electron powder GDT. The GDT exhibiting a voltage class of 470 V was prepared, and its structure and surge characteristics were analyzed. The effects of gas pressure, aging time, and ambient temperature on the breakdown voltage of the graphene GDT were studied. The surge process of the graphene GDT was simulated using the 8/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$20~\mu \text{s}$ </tex-math></inline-formula> impulse current generator, and the resistance ability of the graphene GDT against the surge was examined. Moreover, it was compared with the same type of commercial electron powder GDT. As indicated by the experimental results, a positive correlation was identified between the gas pressure and the dc breakdown voltage of the graphene GDT under a certain pressure. The effect of aging time and ambient temperature on dc breakdown voltage was limited. The breakdown voltage of the graphene GDT was first increased and then decreased with the increase in the number of surges. After 100 surges, the breakdown voltage of the graphene GDT stabilized at 350 V, whose stability was better than that of the electron powder GDT. The above-described analysis confirmed that graphene GDT exhibits better surge resistance ability.

Valley-dependent topological edge states in plasma photonic crystals

Plasma photonic crystals designed in this paper are composed of gas discharge tubes to control the flow of electromagnetic waves. The band structures calculated by the finite element method are consistent with the experimental results which have two distinct attenuation peaks in the ranges of 1‒2.5 GHz and 5‒6 GHz. Electromagnetic parameters of the plasma are extracted by the Nicolson–Ross–Weir method and effective medium theory. The measured electron density is between and which verifies the correctness of the parameter used in the simulation, and the collision frequency is near As the band structures are corroborated by the measured scattering parameters, we introduce the concept of photonic topological insulator based on the quantum Valley Hall effect into the plasma photonic crystal. A valley-dependent plasma photonic crystal with hexagonal lattice is constructed, and the phase transition of the valley () occurs by breaking the spatial inversion symmetry. Valley-spin locked topological edge states are generated and excited by chiral sources. The frequency of the non-bulk state can be dynamically regulated by the electron density. This concept paves the way for novel, tunable topological edge states. More interestingly, the Dirac cone is broken when the electron density increases to which distinguishes from the methods of applying a magnetic field and changing the symmetry of the point group.

Gas discharge tubes for significantly boosting the instantaneous current and active power of load driven by triboelectric nanogenerators

Based on impedance matching of the power management circuit (PMC) with a switch, the instantaneous peak power of triboelectric nanogenerators (TENGs) is significantly improved, recently. However, a high output power of TENGs does not generally mean a high active power consumed by the load, that is low energy utilization efficiency. Here, leveraging plasma discharge, we propose an effective approach by means of a gas discharge tube (GDT), as a rapid switch of a millisecond, resulting in boosting over 4000 times of peak current up to 170.7 mA at a low resistance of 5 Ω. When the TENG runs at 20 Hz, the pulse current occurs every 571.4 ms, and the active peak power also increases to 165.5 mW. With such a high-power output, a 16 W light group can be lit wirelessly even when blocked by a human hand. As commercial discrete components, the GDTs are available in a variety of models, providing a new, cheap, and directly exploitable peak gain option. Similar to diodes, capacitors, and resistors, we are firmly convinced that GDTs will be widely utilized in PMC for TENG.

Многофункциональная система визуализации на основе лазера и усилителя яркости на парах бромида меди

A multifunctional system meant to image the surface of energetic materials during combustion based on copper bromide vapor gain media is proposed. The system allows quickly implement various methods of active visualization and is based on a high-speed video camera, an illuminating laser, and a copper bromide vapor brightness amplifier. Depending on imaging needs, the main components of the system can be configured as a laser-illuminating system, a single-channel laser monitor, or a laser monitor with synchronous laser illumination. A high-voltage pulsed power supply allows connecting both one laser tube and two at the same time, while switching operating modes can be carried out on- the-fly. The source generates one or two synchronized sequences of high-voltage pulses for pumping gasdischarge tubes with a voltage of up to 6 kV and a frequency of 20 kHz. Due to the use of gas discharge tubes with independent control of temperature parameters, the operating modes with a pump power of 500–700 W for each channel can be realized. To generate pump pulses for laser media, a two-channel thyratron circuit for the direct discharge of storage capacitors were used, charged by a common stabilized voltage source provided by a step-down pulse stabilizer and a pulse shaper for charging storage capacitors based on a bridge inverter. A transistor modulator with adjustable delay lines carries out synchronization of the laser illumination and the brightness amplifier in the mode with synchronous laser illumination with an accuracy of ±1 ns.The experimental data of the system operation in various modes are presented. The imaging results for the surface of mixtures of metal nanopowders during combustion, obtained with various configurations of the laser system, are presented.

Study on the performance of open-circuit failure gas discharge tube under the context of DC short-circuit

Protective devices are used at every single port of electrical equipment, such as gas discharge tube(GDT), metal oxide varistors(MOV), and transient voltage suppressors diodes(TVS). These devices are capable to absorb lightning, surge, static electricity and other burst waves by directly spanning across both ends of the circuit or grounding mode. When the protective devices overabsorb these burst waves, short-circuit failure will result. The short-circuit failure of protective devices is one of the potential hazards that would cause combustion. In order to avoid the fault combustion of GDT caused by short-circuit, an open-circuit failure gas discharge tube (OGDT) with the capacity of open-circuit failure is proposed by improving the existing GDT with a high and low temperature sealing solder. This paper focuses on exploring the structure and working mechanism of OGDT, with the open-circuit failure response arc extinguishing time of the OGDT measured by coupling the DC power supply with an 8/20 μs impact current generator. The impact of short-circuit current and DC voltage on OGDT response arc extinguishing time is analyzed by conducting experiments and the effect of OGDT is verified by adjusting the area of low temperature weld. The results show that with the rise of short-circuits current, the open-circuit response arc extinguishing time of OGDT first decreases and then increases. A larger area of the low-temperature welding solder leads to a shorter the response arc extinguishing time. Besides, the higher the applied DC voltage, the shorter the response arc extinguishing time. When the short-circuit current reaches 10 A, the optimal response arc extinguishing time is 300 ms. When the short-circuit current falls below 25 A, the response arc extinguishing time of OGDT can reach a lower level than 1000 ms. The OGDT open-circuit failure action screen is captured by a high-speed camera to verify its outcome. The high-speed camera captures the OGDT open-circuit failure and excision failure at 300 ms, which is consistent with the experimental waveform results. The research results provide practical guidance on the selection of OGDT.

A tunable microwave circulator based on a magnetized plasma as an active gyrotropic element

We present a theoretical analysis and experimental demonstration of a microwave circulator that uses a magnetized plasma as the gyrotropic element. Unlike traditional circulators that exploit the anisotropic permeability of ferrite, here, we exploit the anisotropic dielectric constant of a magnetized plasma to achieve non-reciprocity. The advantage of a plasma-loaded circulator is that it allows for tunability, and modulation that is limited in speed by the ionization/recombination time of the plasma. The theoretical analysis treats the problem of electromagnetic scattering from a heterogeneous gyrotropic plasma rod to confirm scattering behavior and to guide in defining the design parameter space covered by more detailed computational simulations. Proof-of-concept experiments are carried out using a custom-fabricated low-frequency gas discharge tube as the plasma element. Here, we confirm the plasma-frequency dependent tunability predicted by the simulations, demonstrating this tunability in the experiments by varying the applied discharge voltage. These initial experiments suggest that isolation in excess of 25 dB is achievable, in reasonable agreement with the theory and simulations for studies in the S and C ranges of the microwave spectrum.

Investigation into wideband electromagnetic stealth device based on plasma array and radar-absorbing materials

Manipulation of electromagnetic waves is essential to various microwave applications, and absorbing devices composed of low-pressure gas discharge tubes and radar-absorbing materials (RAM) can bring new solutions to broadband electromagnetic stealth. The microwave transmission method is used to measure the physical parameters of the plasma unit. The designed structure exhibits superior absorption performance and radar cross-section (RCS) reduction capability in the 2–18 GHz band, with unique absorption advantage in the S and C frequency bands. It is found that the combination of the plasma and the RAM can significantly broaden the absorption frequency band and improve the absorption performance with excellent synergistic stealth capability. Experimental and simulation results present that broadband, wide-angle, tunable electromagnetic wave absorption and RCS reduction can be achieved by adjusting the spatial layout of the combined plasma layer and the type of RAMs, which creates opportunities for microwave transmission and selective stealth of equipment. Therefore, the wave manipulation by combined plasma array and RAM provides a valuable reference for developing numerous applications, including radar antenna stealth, spatial filter, and high power microwave shielding.

Research on Protection Performance of Surge Protective Devices against Electromagnetic Pulse.

To evaluate the protection performance of SPD (surge protective device) against electromagnetic pulse, the response ability of several typical surge protective devices to wide and narrow electromagnetic pulses was tested by using a SPD response ability test system. The results showed that SPD commonly used in lightning surge protection had certain ability to suppress electromagnetic pulse conduction disturbance. Gas discharge tubes presented typical clamping characteristics for wide pulses. MOV and TVS had obvious clamping effect on wide pulses, while had no clamping effect on narrow pulses, but could obviously reduce its peak value. Zener diodes had obvious clamping effect on narrow pulses, and the clamping voltage control accuracy was high.

Machine Learning Based Prediction for the Response of Gas Discharge Tube to Damped Sinusoid Signal

In order to predict the circuit response of a Gas Discharge Tube (GDT) to an electromagnetic pulse, a “black box” model for a GDT based on a machine learning method is proposed and validated in this paper.Firstly, the machine learning model of the Elman neural network is established by taking advantage of the existing measurement data to dampen the sinusoid signal, and then the established model is adopted to predict the response waveform of an unknown injection current grade and frequency.Without considering the complex physical parameters and dynamic behavior of GDTs, the Elman neural network modeling method is simpler than the existing physical or Pspice model.Validation experiments show a good agreement between the predicted and the measured waveforms.

Reliability improvement of gas discharge tube by suppressing the formation of short-circuit pathways

After cumulative discharge of gas discharge tube (GDT), it is easy to form a short circuit pathway between the two electrodes, which increases the failure risk and causes severe influences on the protected object. To reduce the failure risk of GDT and improve cumulative discharge times before failure, this work aims to suppress the formation of two short-circuit pathways by optimizing the tube wall structure, the electrode materials and the electrode structure. A total of five improved GDT samples are designed by focusing on the insulation resistance change that occurs after the improvement; then, by combining these designs with the microscopic morphology changes inside the cavity and the differences in deposition composition, the reasons for the differences in the GDT failure risk are also analyzed. The experimental results show that compared with GDT of traditional structure and material, the method of adding grooves at both ends of the tube wall can effectively block the deposition pathway of the tube wall, and the cumulative discharge time before device failure is increased by 149%. On this basis, when the iron-nickel electrode is replaced with a tungsten-copper electrode, the difference in the electrode’s surface splash characteristics further extends the discharge time before failure by 183%. In addition, when compared with the traditional electrode structure, the method of adding an annular structure at the electrode edge to block the splashing pathway for the particles on the electrode surface shows no positive effect, and the cumulative discharge time before the failure of the two structures is reduced by 22.8% and 49.7%, respectively. Among these improved structures, the samples with grooves at both ends of the tube wall and tungsten-copper as their electrode material have the lowest failure risk.