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.

Round-trip oscillation triboelectric nanogenerator with high output response and low wear to harvest random wind energy

Triboelectric nanogenerator(TENG)has made significant progress in wind energy harvesting.As the most advantageous rotary TENG among wind energy harvesters,the severe material wear and the output that fluctuates with wind speed seriously hinder the application of TENG wind energy harvesters.In this study,we propose a round-trip oscillation triboelectric nanogenerator(RTO-TENG)consisting of a crank transmission mechanism and a power generation unit.The RTO-TENG utilizes a simple crank transmission mechanism combined with a zigzag-laminated triboelectric nanogenerator(Z-TENG)to achieve high-performance constant output and low material wear.The crank transmission mechanism can realize the transformation from circular motion to arc reciprocating motion,converting the random wind energy into bi-directional kinetic energy,driving the vertical contact and separation of the Z-TENG.Due to the low transmission ratio(1:1)of the crank transmission mechanism and the consistent frequency of the Z-TENG contact–separation with that of the pendulum,the RTO-TENG’s power generation unit(10 Z-TENGs)is insensitive to changes in wind speed,resulting in a constant and stable output response at various speeds.After 480,000 cycles,the output of RTO-TENG decreased by only 0.9%compared to the initial value of 6μC,and the scanning electron microscopy(SEM)images of the polytetrafluoroethylene(PTFE)film showed no significant wear on the surface of the friction layer,demonstrating excellent output stability and abrasion resistance of the RTO-TENG wind energy collector’s material.The equipped energy management module,based on a gas discharge tube switch,can further enhance the output performance of the RTO-TENG.After optimizing its inductor parameter L to match the load capacitor,it can charge a 220μF load capacitor to 13.4 V in 40 s,resulting in a 298%improvement in charging speed compared to the voltage of 4.48 V without the management module.Therefore,the RTO-TENG can efficiently provide power to low-power small electronic devices for Internet of Things(IoTs),such as road traffic warning signs and thermo-hygrometers.