This paper starts with lithium-ion battery thermal management using a liquid-cooled BTMS. It then reviews recent design improvements for liquid-cooled systems, covering cooling liquid, system structure, and hybrid setups. These insights enhance lithium-ion battery cooling system optimization.

Silicone rubber insulation material is widely used for the external insulation of power systems. During the continuous service of a power grid, it will be seriously aged due to the influence of high voltage electric fields and harsh climate environments, which will reduce its insulation performance and service life and cause transmission line failure. How to evaluate the aging performance of silicone rubber insulation materials scientifically and accurately is a hot and difficult issue in the industry. Starting from the composite insulator, which is the most widely used insulating device of silicone rubber insulation materials, this paper expounds the aging mechanism of silicone rubber materials, analyzes the applicability and effectiveness of various existing aging tests and evaluation methods, especially discusses the magnetic resonance detection methods emerging in recent years, and finally summarizes the characterization and evaluation technology of the aging state of silicone rubber insulation materials.

Differences in copper (Cu) absorption and transport, physiological responses and structural characteristics between two types of Cu-resistant plants, Oenothera glazioviana (Cu-exclusion type) and Elsholtzia haichowensis (Cu-enrichment type), were investigated in the present study. The results indicated the following: (1) After 50 μM Cu treatment, the Cu ratio in the xylem vessels of E. haichowensis increased by 60%. A Cu adsorption experiment indicated that O. glazioviana exhibited greater resistance to Cu, and Cu absorption and the shoot/root ratio of Cu were significantly lower in O. glazioviana than in E. haichowensis. (2) An analysis of the endogenous abscisic acid (ABA) variance and exogenous ABA treatment demonstrated that the ABA levels of both plants did not differ; exogenous ABA treatment clearly reduced Cu accumulation in both plants. (3) The leaf stomatal density of O. glazioviana was significantly less than that of E. haichowensis. Guard cells in E. haichowensis plants were covered with a thick cuticle layer, the epidermal hair was more numerous and longer, and the number of xylem conduits in the root was small. (4) The transpiration rate and the stomatal conductance of O. glazioviana were both significantly lower than those of E. haichowensis, regardless of whether the plants were treated with Cu. Taken together, these results indicate that the differences in the structural characteristics between these two plant species, particularly in the characteristics related to plant transpiration, are important factors that govern whether plants acquire or exclude Cu.

To measure the current on each conductor in a three-phase three-core cable or a three-phase four-core cable without an armor or the armor that is made of nonmagnetic material, one has to remove its sheath/armor and applies a traditional device, such as a current transformer (CT) to each conductor, which is invasive and inconvenient. In this article, a Coreless current probe, composed of a tunnel-magnetoresistance (TMR)-based magnetic sensor array, is presented to nondestructively achieve current measurement for multicore cables. The conductor positions, incline angles, and current phasors of a multicore cable are simultaneously identified by solving a nonlinear least square (NLLS) problem. The current waveforms are reconstructed in real time through a real-valued matrix multiplication using the measured time-domain TMR sensor voltage signals. Both simulation and experiment are performed to validate the feasibility of the proposed method. The simulation study is first conducted and demonstrates that a maximum relative current amplitude error of less than 5% and a maximum phase error of lower than 4° can be achieved, and three-phase current waveforms with many harmonics are also successfully reconstructed by simulation. A prototype Coreless current probe is designed and fabricated. The experimental study involving fundamental current phasor measurement and current waveform reconstruction is subsequently performed on a three-phase three-core cable. The experimental results indicate that the maximum relative current amplitude error and phase error, respectively, have average values of 5.44% and 2.58°. Meanwhile, three-phase current waveforms with many harmonics generated by three types of appliances are also successfully reconstructed.

The improvement of water management in agriculture by exactly detecting moisture parameters of soil is crucial. To investigate this problem, a mini inside-out nuclear magnetic resonance sensor (NMR) was proposed to measure moisture parameters of model soils. This sensor combines three cylindrical magnets that are magnetized in the axial direction and three arc spiral coils of the same size in series. We calculated and optimized the magnet structure by equivalent magnetization to current density. By adjusting the radius and height between the cylinders, a circumferential symmetric constant gradient field (2.28 T/m) was obtained. The NMR sensor was set at 2.424 MHz to measure the water content of sandy soil with small particle diameter and silica sand with large particle diameter. The complete decaying, an NMR signal was analyzed through inverse Laplace transformation and averaged on a T₂ space. According to the results, moisture content of the sample is positively correlated with the integral area of T₂ spectrum peak (A_peak); T₂ of the water in small pores is shorter than that in large pores, because the movement of water molecules are limited by the inner wall of the pores. In the same volume, water in large pore sample is more than that in small pore sample, so A_peak of silica sand is larger than A_peak of sandy soil. Therefore, the sensor is capable of detecting moisture both content and pore size of the sample. This mini sensor (4.0 cm in diameter and 10 cm in length) is portable, and the lowest measurable humidity is 0.38%. Thus, this sensor will allow easy soil moisture measurements on-field in the future.

Silicone rubber insulators (SRIs) play an important role in high-voltage power transmission lines. Given that SRIs critically threatens the safe operation of the power grid, quantitatively assessing the aging status of SRIs in situ is crucial. In this paper, a portable unilateral magnetic resonance (UMR) sensor with U-shaped magnet structure and its measuring circuit were designed for the nondestructive detection of the aging status of SRIs in situ. First, the optimization efficiency of the magnet structure was improved through a uniform design method. Then, the planar radio frequency (RF) coil was designed by the finite element method. Furthermore, the demagnetization effect of eddy currents induced in metal materials on the RF magnetic field was analyzed. We measured the SRI sheds at different service times and obtained the corresponding 1H transverse relaxation decay curves by importing Carr-Purcell-Meiboom-Gill (CPMG) sequence. Finally, the transverse relaxation decay curves were post-processed using inverse Laplace transformation, and the 1-D spectrum distributions of transverse relaxation time (T2) were obtained. Results reveal that the T2 of the surface of the SRI shed decreases as the service time of the SRI increases. Additionally, the difference in T2 between the surface and interior of the SRI shed increases. The comparison experiments demonstrate that the U-shaped sensor designed in this paper is superior to the curved sensor previously designed by our team. The effect of temperature variation on SRIs aging assessment was taken into account at last.