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• Perovskite ZnSnO 3 cubes were synthesized hydrothermally. • The β -phase transformation was induced by the shear stress between ZnSnO 3 and PVDF. • A maximum piezo-potential of 41.5 V by the optimal case was achieved. • The maximum power density of 50.6 μW cm−2 was acquired. Flexible self-powered electromechanical devices, such as piezoelectric nanogenerators (PENGs), which are used in wearable and implantable devices, are emerging as state-of-the-art clean energy sources. In this study, a scalable supersonic spraying technique was used to prepare flexible piezocomposite films of polyvinylidene fluoride (PVDF) and hydrothermally synthesized ZnSnO 3 (ZSO) cubes for PENGs. Raman spectra confirmed that the transformation of the α -phase of PVDF to its β -phase was induced by the shear stress generated between the ZSO particles and PVDF polymer during supersonic spraying. The optimized sample comprising 0.43 g of ZSO cubes and 1 g of PVDF produced a maximum piezopotential of 41.5 V and a short-circuit current, I sc , of 52.5 μA. A maximum power density of 50.6 μW cm−2 was obtained at a loading resistance of 0.4 MΩ, which matched the impedance of the PENG. Long-term tapping and bending cycles of N tap = 4200 and N bend = 600 yielded piezopotentials of 40.5 and 1.7 V, respectively. In addition, electrical poling for 2 h increased the piezopotential to 52 V owing to the alignment of the ferroelectric dipoles in the PVDF. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose: In the event of a DC short-circuit fault in a flexible DC power grid, the high peak value of the fault current puts forward more stringent requirements on the DC circuit breaker. The existing fault current cutoff mainly focuses on changing the topology structure. To suppress the development of fault current and reduce the investment cost of the DC grid, this paper aims to propose a dual-loop active current-limiting control based on energy difference. Design/methodology/approach: Firstly, the equivalent circuit at fault is established, and the parameters related to the fault current are analyzed. Then, the relationship between the output voltage change of the bridge arm and the difference between the AC and DC energy is deduced. Finally, the experimental results are discussed on the real-time simulation platform Opal-RT. Findings: The proposed current-limiting measures can greatly reduce the fault current, reduce the breaking current of the circuit breaker and increase the capacitor voltage during the fault period, which is beneficial to the stability of the AC system. It is verified that the proposed method is also applicable to a certain high-resistance fault. Originality/value: This paper applies the method of AC fault to DC fault and deduces the relationship between energy difference and voltage variation corresponding to different step lengths based on digital simulation. In addition, two variables are used as control structure parameters to reduce the probability of system misoperation. [ABSTRACT FROM AUTHOR]

• Tetramethylammonium chloride (TMACl) effectively improves film quality and optoelectronic properties of CsPbI 2 Br. • The CsPbI 2 Br-based device with TMACl achieves impressive efficiencies of 14.12% and 27.16% under 1-sun and white light-emitting diode irradiation, respectively. • TMACl also improves hydrophobicity of CsPbI 2 Br to enhance ambient stability of devices. Although all-inorganic perovskites possess suitable bandgap and thermal stability for photovoltaic applications, the unstable film morphologies, and poor moisture stabilities lag behind the organic-inorganic hybrid counterparts. Herein, we demonstrate that high quality α-CsPbI 2 Br films with improved phase stability, high crystallinity, and pinhole-free film morphology was achieved by employing tetramethylammonium chloride (TMACl) as an additive. As a result, the TMACl-added CsPbI 2 Br films exhibited high power conversion efficiency of 14.12% with an open-circuit voltage of 1.19 V, a short-circuit current density of 15.08 mA/cm2, and a fill factor of 0.78. More importantly, the TMACl addition imparts hydrophobicity to the film surface of CsPbI 2 Br, which delivered excellent stability up to 30 days in the ambient condition and thermal stability at 85 °C for 156 h, respectively. Moreover, the TMACl-added device also exhibited excellent PCE of 27.16% under indoor light source (1000 lux), which presents a promising approach for designing stable but high performance all-inorganic perovskite solar cells. [Display omitted] [ABSTRACT FROM AUTHOR]

• The reported TENGs were fabricated by taking full advantages of electronegativity, metal conductivity, multilayer structure of Ti 3 C 2 T x MXene. • This work provides an enhanced way to fabricate wearable electronics integrated with smart functions. • Integrating super flexibility, highly efficient EMI shielding performance, self-repair, self-powering, and sensing ability broadens the applications. Integrating smart functions into one flexible electronic is vastly valuable in improving their working performances and broadening applications. Here, this work reports a ultraflexible, highly efficient electromagnetic interference (EMI) shielding, and self-healable triboelectric nanogenerator (TENG) that is assembled by modified Ti 3 C 2 T x MXene (m -MXene)-based nanocomposite elastomers. Benefitting from the excellent electronegativity of m -MXene, the single-electrode mode-based TENG can generate high open-circuit voltage (V oc) oscillating between − 65 and 245 V, high short-circuit current (I sc) of 29 µA, and an instantaneously maximum peak power density of 1150 mW m−2 that can power twenty light-emitting diodes (LEDs). Moreover, the resultant TENG possesses outstanding EMI shielding performance with the maximum shielding effectiveness of 48.1 dB in the X-band. The enhanced shielding capability is dominated by the electromagnetic absorption owning to high conduction loss in m -MXene network, multiple reflections between m -MXene sheets, and polarization effect on the surface of m -MXene sheets. Additionally, a self-powered wearable sensor is fabricated based on the as-prepared TENG. The sensor shows an intrinsic healing ability with healing efficiency of 98.2% and can accurately detect the human large-scale motions and delicate physical signal. This work provides an enhanced way to fabricate the wearable electronics integrated with smart functions, and the reported MXene-based TENG may have a broad prospect in the fields of aerospace, artificial intelligence, and healthcare systems. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose For the proposed coupling transformer, a magnetic bypass based on the virtual air gap principle is realized by inserting auxiliary windings in a return leg added to a standard transformer. With such a setup, it is able to act as a voltage regulator as well as protect the power electronics of the dynamic voltage restorer from electrical grid fault currents. This paper focuses on the electrical design part of the coupling transformer. It aims to explain how the behavior of the auxiliary windings electrical circuit of the magnetic bypass impacts the performances of the device.Design/methodology/approach The influence of the electrical auxiliary windings circuit configurations on the operation of the coupling transformer is studied by finite element analyses with nonlinear and isotropic magnetic materials.Findings A configuration for the realization of the electrical circuit of the auxiliary windings is determined according to the finite element simulation results to achieve the design of the coupling transformer whose magnetic core was previously designed.Originality/value By studying the operation of a special coupling transformer with nonlinear saturation phenomenon by finite element analyses, a to-do list of the electrical circuit parameters is described to design this device well. [ABSTRACT FROM AUTHOR]

Flash memory is an important component in many embedded system-on-a-chip applications, which drives the need to generate high write/erase voltages in generic CMOS processes. In this paper, we present a regulated, high-voltage charge pump for erasing Flash memory and floating-gate transistors. This 0.069-mm2 charge pump was fabricated in a 0.35 \mu \text m standard CMOS process. While operating from a 2.5 V supply, the charge pump generates regulated voltages up to 16 V with a PSRR of 52 dB and an output impedance of 6.8 \textk\Omega . To reduce power consumption for use in battery-powered applications, this charge pump uses a variable-frequency regulation technique and a new circuit for minimizing short-circuit current in the clock-generation circuitry; the resulting charge pump is able to erase the charge on floating-gate transistors using only $1.45 \mu J$ . [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to investigate a five-phase permanent-magnet synchronous machine (PMSM) that features high-power density and high-fault-tolerant capability for electric vehicles (EVs). Design/methodology/approach – The five-phase 20-slot/18-pole PMSM is designed by finite-element method. Two typical rotor structures which include Halbach array and rotor eccentricity are compared to achieve sinusoidal back electromotive force (EMF). The influence of slot dimensions on leakage inductance and short-circuit current is analyzed. The method to reduce eddy current loss of permanent magnets (PMs) is investigated. The machine performances under both healthy and fault conditions are evaluated. Finally, thermal behavior of the machine is studied by Ansys. Findings – With both no-load and load performances considered, rotor eccentricity is proposed to reduce the harmonic contents of EMF. Increasing slot leakage inductance is an effective way to limit the short-circuit current. By segmenting PMs in circumferential direction, the PM eddy current loss is reduced and the machine efficiency is improved. With proper fault-tolerant control strategy, acceptable torque performance can be achieved under fault conditions. The proposed machine can safely operate under Class F insulation. Originality/value – So far, many researches focus on multiphase PMSMs used in aviation fields, such as fuel pump and electric actuator. Differing from PMSMs used in aviation applications, machines for EVs require characteristics like wide speed ranges and variable operating conditions. Hence, this paper proposes a five-phase 20-slot/18-pole PMSM for EVs. The proposed design methodology is applicable to multiphase PMSMs with different slot/pole combinations. [ABSTRACT FROM AUTHOR]

Imagine a blazingly hot day in central China, when all the air conditioners in every megacity are running at full blast. Through the remote mountains of Shanxi province, the major transmission lines that carry ultrahigh-voltage electricity to the cities are operating at close to maximum capacity. [ABSTRACT FROM PUBLISHER]

Switching speed, active power consumption, standby leakage current, and silicon area are major concerns in buffer design. A new Skewed-IO cell with two split inputs and two split outputs is proposed for low-leakage and high-speed buffer design in this paper. The triple-threshold-voltage buffers with the new Skewed-IO cells offer up to 68.3% and 13.2% reduction in standby leakage currents and propagation delay, respectively, as compared to the conventional static CMOS inverter based buffers under identical load capacitance conditions in a TSMC 65 nm CMOS technology. [ABSTRACT FROM AUTHOR]

The article offers suggestions by the readers of the periodical regading personal computers, software, and websites. Topics discussed include use of dark theme provides long battery lasting of the laptops advised by the Microsoft; ways to save device if dropped in water or water spillage to devices by taking gadgets to the specialist for repairing otherwise it would short-circuit and stop working; and use of Photoboxto directly print Google Photos snaps.

Maxim Presents MAX22513 IO-Link Transceiver with Reverse-Voltage and Short-Circuit Protected IO Pins - Apr 03, 2019 - Maxim Integrated [ABSTRACT FROM AUTHOR]

DC/DC ATX power supply sports ultra-wide input range for embedded box PCs in industrial, medical, and auto applications. [ABSTRACT FROM AUTHOR]

The article presents questions and answers related to model railroads including how to solve the issue of short-circuit in metal wheels while using the digital command control (DCC) technique and what cement should be used while constructing model railroads.

The article focuses on damages caused to China's cultural heritage sites due to electrical fires. Topics discussed include damage caused to China's ancient city gate tower Gongchen Tower due to fire in Yunnan Province, China, report of the China's State Administration of Cultural Heritage which states that country's heritage buildings are affected by 40 percent of electrical fires, and short-circuit due to overcrowding.