To comparatively evaluate the suitability of superhydrophobic and superhydrophilic coatings for photovoltaic (PV) module surfaces in arid and low-rainfall regions, this study investigates their dust deposition mitigation performance under anhydrous conditions and assesses the impact of dust reduction on PV power generation efficiency. An experimental platform for dust deposition and a PV output measurement system were constructed to evaluate the performance of coated PV modules. The open-circuit voltage (U_oc), short-circuit current (I_sc), maximum power (P_max), and dust deposition mass were measured before and after dust exposure. Additionally, the influence of coating properties on dust deposition behavior and the correlation between dust deposition density and PV output power were systematically examined. The experimental data reveal a linear relationship between PV output power loss and dust deposition density. Dust accumulation decreases monotonically with panel tilt angle, while displaying a non-monotonic response to wind speed, peaking at 3.9 m/s. Under optimal conditions (60° tilt angle and 5.2 m/s wind speed), minimal dust deposition densities were observed: 0.25 g/m² for superhydrophobic coated PV modules versus 1.11 g/m² for superhydrophilic coated surfaces. Both superhydrophobic and superhydrophilic coatings demonstrated effective dust deposition inhibition in anhydrous environments. However, the dust deposition mitigation efficiency of the superhydrophobic coating (88.7%) is significantly better than that of the superhydrophilic coating (46.2%) under the working conditions of a large inclination angle (60°) and high wind speed (5.2 m/s). These findings provide critical experimental evidence for optimizing self-cleaning coating selection in PV modules deployed in arid regions.

A short-circuit fault in the gas discharge tube (GDT) is one of the latent hazards of electrical equipment. It may cause the ignition of electrical equipment. Therefore, based on the existing GDT, an improved external open-circuit failure gas discharge tube (EOFGDT) which can remove short-circuit (SC) failure is presented in this paper, and its structure and working mechanisms are introduced. This EOFGDT can utilize the combustion and heat transfer of continuous arcs due to SC failures to increase the temperature of its end electrode, so as to induce a solder joint failure, by which the elastic sheet on the solder joint becomes disconnected from the end electrode, forming an external gap that reduces the rising speed and amplitude of the recovery voltage across the arc gap, and eventually forms an open circuit (OC) within the structure. The EOFGDT SC condition was simulated and a test of the EOFGDT ability to remove SC faults by using an 8/20 µs impulse current generator coupled with a power-frequency power supply test bed was conducted. The experimental results show that the magnitude of the SC follow currents, power-frequency voltages, and the impulse currents are positively correlated to the OC response time, which is greatly affected by the power-frequency follow currents. When the SC current reaches 30 A, the EOFGDT OC response time is about 350 ms. The experimental waveform is consistent with the screen result of the OC response time of the EOFGDT, which proves the effectiveness of EOFGDTs for the inhibition of SC follow-current failures.