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Medium voltage DC (MVDC) power system has the characteristics of low line impedance, resulting in high peak and fast rise rate of the fault current. For example, the current in an onboard 10kV DC grid can rise to more than 40 kA in 3 ms after the failure. Therefore, it is necessary to configure DC circuit breaker (DCCB) with high current breaking capacity. In this paper, a novel high-power hybrid DC breaker based on integrated commutation compound power electronic switch is proposed. By giving full play to the complementary advantages of IGBT and IGCT, and skillfully integrating the commutation function into the power electronic switch, the proposed DC breaker has the characteristics of low cost, compact, high performance, and can also play a role in current limiting. The working principle of the proposed scheme is described in detail, and a 10 kV prototype with 40 kA current breaking ability is built to verify its feasibility.

For new renewable clean energy, triboelectric nanogenerators (TENGs) have shown great potential in response to the world energy crisis. Nevertheless, the alternating-current signal generated by a TENG needs to be converted into a direct-current signal to be effective in applications. Therefore, a power management circuit, comprising a clamp rectifier circuit and a mechanical switch, is proposed for the conversion and produces a signal having a low ripple coefficient. The power management circuit adopts a clamp circuit as the rectifier circuit to increase the rectified voltage, and reduces the loss resulted from the components by reducing the use of discrete components; the electronic switch in the buck regulator circuit is replaced with a mechanical switch to reduce cost and complexity. In a series of experiments, this power management circuit displayed a stable output voltage with a ripple voltage of 0.07 V, crest factor of 1.01, and ripple coefficient of 2.2%. The TENG provides a feasible method to generate stable electric energy and to supply power to low-consumption electronic devices.

The fault current of the high‐voltage and large‐capacity flexible DC power grid has the characteristics of a fast rising rate, high peak value, and large influence area; therefore, fault current suppression equipment suitable for the flexible DC power grid has become a research hotspot. First, the fault mechanism and fault current calculation associated with the DC converter are analysed in this study; subsequently, a multiport superconducting fault‐current‐limiting circuit breaker (SFCLCB) suitable for a flexible DC power grid is designed. The circuit breaker adopts ground drainage to transfer the fault current. It only needs to be equipped with a single‐way conduction power electronic switch group and the number of switches is not affected by the number of DC lines, considerably improving the cost effectiveness of the equipment. In addition, the workflow and current‐limiting principle of SFCLCB are analysed, and the optimal matching method is determined with respect to the resistance of the superconducting current limiter and the power electronic devices of the main circuit breaker. Afterwards, the four‐terminal flexible DC transmission simulation system is observed to exhibit high efficiency in suppressing the fault current and high cost effectiveness based on comparative simulations. Finally, its engineering applicability is verified by the digital physical and hybrid simulation platform.

We present carrier-injection-based photonic switches, engineered for optical pulse distribution with maximum energy efficiency. We apply small-signal analysis and for the first time large-signal modelling to methodically optimize the switches for minimum energy consumption and to classify the electronic contributions from resistance, capacitance, and diode. We present optimized electronic switch activation, which yields a sixfold reduction in energy consumption and we show how static power consumption becomes a negligible factor for optical pulse switching. We demonstrate that with adjusted phase shifter dimensions, MZI-based switches can operate with additional 50% enhanced energy efficiency with down to 4 pJ per switching operation. We show even further efficiency improvement using ring-based designs, allowing an additional improvement of 50% in energy efficiency and we discuss the trade-off between efficiency and optical bandwidth associated to the Q-factor. We benchmark carrier-injection-based switches together with comparable technologies of the silicon photonics platform and identify carrier-injection to be the most suitable technology for pulse switching applications.

In a voltage-source converter dc grid, a dc fault current limiter (FCL) is a key apparatus. When faults occur, it is supposed to effectively and immediately suppress transient short-circuit current to protect other equipment, e.g., converters. Additionally, it is required to bring as little negative effect as possible under normal operation. Although the respective advantages are highlighted in different FCLs, one or two key disadvantages can significantly decrease the overall performance. In this article, a novel magnetic coupling FCL (MCFCL) is proposed and achieves a good balance among its advantages and disadvantages. An MCFCL consists of a mutual inductor and some power electronic switch modules. The mutual inductor metallic primary winding is connected in series to the transmission line and magnetically coupled with the secondary winding. The secondary side impedance is controlled by the power electronic switch modules. The novel 4-segment model is proposed to demonstrate the current-limiting physics, formulate the current-limiting effect, and support the design. One medium voltage (10 kV) case study is carried out based on the numerical simulation. The MCFCL shows a better current-suppressing effect and a lower impedance under normal operation than the benchmark Reactor FCL. Finally, this article is validated on a scaled-down experimental facility.

DC system has the potential of vast and rapid fault current generation due to multiple (line and converters) discharge capacitors and small impedance of DC lines. DC fault current spreads through the system exponentially compared to AC. Such an unexpected huge current causes a voltage drop, impacts the normal operation of system components and exposes the system to a great challenge for fault detection and interruption. For prevention of system destruction during the fault, multiple approaches such as application of Mechanical Circuit Breakers (MCBs), fuses, Solid State Circuit Breaker (SSCB), and Hybrid Solid-State Circuit Breaker (HSSCB) have been proposed and applied. In DC fault applications, fast fault detection and interruption without any interference to the other components are quite important. Therefore, semiconductor breakers have been implemented to meet the DC fault protection requirements with a high-speed operation where traditional MBs have failed. Due to the high conduction loss and low efficiency of semiconductor switches, for fast and efficient DC fault interruption, different Fault Current Limiter (FCL) types are suggested. Although a high impedance FCL can prevent the voltage fluctuations due to the current decline, it can cause operation speed issues, coordination troubles, overheat, and malfunction of protective components in a fault situation. This paper focused on a combination of two-way HSSCB with a self-adapt DC short current limiter, ultra-fast switch, and power electronic switch to overcome the above challenges. It can efficiently and fast fault current limiting response with low conducting loss and appropriate cooperation among protective components in a low voltage DC system. The MATLAB/Simulink is used to analyze the effectiveness and consistency of the proposed FCL-HSSCB in 400 V interconnected standalone DC microgrids.

Robust fault analysis (FA) including the diagnosis of faults and predicting their level of fault severity is necessary to optimize maintenance and improve reliability. This study aimed at presenting a technique to diagnosis faults of electronic switch in permanent magnet synchronous motor in Aircraft. The current output of both thyristor bridges and the diode of system excitation is monitored under healthy and faulty operations. Features extracted at different operations using Multi-scale wavelet decomposition (MSWD) to extract the useful features. MSWD features are used to train nonlinear autoregressive with exogenous model which sequentially operated to evaluate the fault level in case open circuit that developing across a switch under different operating condtions. The two models have been tested and designed due to the simulated data, where the results showed acceptable effectiveness in the diagnosis of various types of fault.

A 1 bit single-polarization broadband space-time-coding digital metasurface element with a zero cross polarization is proposed. This element consists of a modified patch, an electronic switch, a dc-bias network, a ground plane, and two-layer dielectrics. The upper patch with edge loading and centered square hole is fully optimized to achieve broadband and stable phase difference between two states. By electronically controlling the diode, the element achieves a 1 bit phase shift with a relative bandwidth of 20% within 180° ± 30° from 7.71 to 9.43 GHz. Moreover, a negligible cross polarization is obtained due to the uniaxial symmetry of the structure, and the amplitude loss is less than 0.8 dB for two states. The experimental results measured in a rectangular waveguide are well matched with the simulations, further demonstrating validity of the proposed element.

Beaufort scale of wind force monitoring is the basic content of meteorological monitoring, which is an important means to ensure the safety of production and life by timely warning of natural disasters. As there is a limited battery life for sensors, determining how to reduce power consumption and extend system life is still an urgent problem. In this work, a near-zero power triboelectric wake-up system for autonomous Beaufort scale of wind force monitoring is proposed, in which a rotary TENG is used to convert wind energy into a stored electric energy capacitor. When the capacitor voltage accumulates to the threshold voltage of a transistor, it turns on as an electronic switch and the system wakes up. In active mode, the Beaufort scale of wind force can be judged according to the electric energy and the signal is sent out wirelessly. In standby mode, when there is no wind, the power consumption of the system is only 14 nW. When the wind scale reaches or exceeds light air, the system can switch to active mode within one second and accurately judge the Beaufort scale of wind force within 10 s. This work provided a triboelectric sensor-based wake-up system with ultralow static power consumption, which has great prospects for unattended environmental monitoring, hurricane warning, and big data acquisition.

In many industry applications, the self-locking and interlocking switches are usually used to control electrical equipment or applied to automation control. The electronic self-locking /interlocking switches can improve the disadvantages of the conventional self-locking/interlocking switches using relay types; however, they can not achieve the real interlocking state when two push buttons are pressed at the same time. In this paper, a fully self-locking/interlocking electronic switch circuit based on MOSFET is proposed to solve the above problem by using a technology of signal mutual control.

When HVDC transmission systems operate in the ground return mode, transformers in adjacent ac systems frequently suffer half-cycle saturation. In this two-part paper, an effective mitigation method using power electronic switches is proposed that does not compromise the ability of the protection system to detect fault currents. In Part I, a study is conducted to find the physical performance of the half-cycle saturation and give a technical solution to the inrush-like half-cycle saturated currents. Power electronic switches, opening the neutral connection to ground, are utilized to mitigate the saturation without compromising the reference ground of the transformer. The determination of the switch parameters, switching frequency, and duty cycle is performed. Details of the mitigation transient are studied by comparing simulations and laboratory experiments to validate the efficacy of the proposed power electronic switch for the mitigation of half-cycle saturated currents. In Part II, the influence of the proposed switch on the detection of ground faults is investigated. Proper parameter and operation strategies are selected to effectively detect the ground faults and ensure the fast response of protective relays. The techniques proposed are applicable to mitigate geomagnetically induced current.

This paper presents a fiber Bragg grating (FBG) interrogator based on vertical surface cavity emitting lasers (VCSEL). A Fabry–Perot filter technique is developed to directly calibrate the dynamic wavelength behavior of VCSELs at both low and high sweep rates. A broad bandwidth light source is constructed by multiplexing five VCSELs together to increase the number of FBGs that can be tracked. Scanning of the VCSEL-array is accomplished by a high-speed electronic switch circuit. The developed interrogator achieves a sweep bandwidth of 10 nm at a scanning rate of 4 kHz. Low-velocity impact testing of a composite plate with a surface mounted FBG sensor shows that the wavelength detection error was 2.7% when compared with the FBG strain obtained by a high-speed swept laser.

In this paper, direct current (DC) fault current limiting and interrupting operation of hybrid DC circuit breaker (DCCB) using double quench, which consists of DCCB, a series resonance circuit, power electronic switch, surge arrestor, two separated current limiting reactor/resistor, and two superconducting elements, were suggested. The suggested hybrid DCCB can perform the interrupting operation after twice or once DC fault current limiting operation according to DC fault current amplitude. To verify the effective operation of the suggested hybrid DCCB, the modeling for the components of DCCB, the surge arrestor, and the SCE was carried out and its DC operational characteristics were analyzed. Through the analysis of the modeling results for the suggested hybrid DCCB, the advantages of hybrid DCCB were discussed.

The measurement of grounding impedance has a high requirement for the instrument. In this paper, a method of measuring the power frequency interval wave of large-scale grounding device is proposed, which is studied from three aspects: principle, implementation and field application. The interval wave method outputs the interval voltage signal of power frequency through synchronous high-speed acquisition and power electronic switch, and then removes the influence of field noise by forward and backward difference of adjacent cycle signal. The noise of different types of strong interference is measured in the field, and the denoise performance of the interval wave method is analyzed by simulation. The application of the interval wave method in the measurement of the grounding impedance of a 500kV substation is realized, and the effectiveness of the method is proved by comparing with the different frequency method. The research results of this paper provide a reference for the lightening and intelligence of grounding impedance measurement equipment.

Single-phase grounding faults are the most common type of faults in power distribution systems. Due to the large number of branches and the coexistence of overhead lines and cable lines, the single-phase grounding faults is difficult to locate accurately. In response to this problem, a single-phase grounding fault distance measurement technology for distribution lines based on active disturbance is proposed. When a single-phase grounding fault occurs in the distribution line, the power electronic switch used to switch the damping resistance of the arc suppression coil is switched off for a short time, so that the transient disturbance waveforms of the voltage and current with controllable intensity and characteristics can be produced. At the waveform measurement point of the feeder, based on the multi-frequency components in the effective frequency band of the disturbance voltage and current, the fault distance measurement equations are established. Then by using the hypothesis testing method and comparing the residuals of the fault distance measurement equations, the fault section is determined and the fault distance are provided. Due to the rich frequency components contained in the disturbance, the method can be applied to the fault location of the radial distribution network composed of mixed lines. It also can eliminate the falsity of the fault points and reduce the error caused by the changes of line parameters.

In this paper, a Marx generator voltage multiplier as an impulse generator made of multi-stage resistors and capacitors to generate a high voltage is proposed. In order to generate a high voltage pulse, a number of capacitors are connected in parallel to charge up during on time and then in series to generate higher voltage during off period. In this research, a 6kV Marx generator voltage multiplier is designed using gas discharge tube (GDT) as an electronic switch to breakdown voltage. The Marx generator circuit is designed to charge the storage capacitor for high impulse voltage and current generator applications. According to IEC 61000-4-5 class 4 standards, the storage capacitor must be charged up to 4 kV. The results show that the proposed Marx generator can produce voltages up to 6.8 kV. However, the storage capacitor could be charged up to 1 kV, instead of 4 kV in the standard. That is because the output impulse voltage has narrow time period.

With the increase of multi-terminal flexible DC distribution network projects, medium-voltage DC circuit breaker, as the key equipment to remove DC short-circuit fault, plays a key role in the operation reliability of the whole DC distribution network. In order to meet the engineering needs of DC distribution network, a 10kV hybrid DC circuit breaker based on the coupling negative voltage principle is developed in this paper. Firstly, the topology and working principle of the DC circuit breaker are introduced. Furthermore, the design scheme of key components including fast mechanical switch, power electronic switch and coupling negative voltage device is given. Finally, a 10kV hybrid DC circuit breaker prototype is developed and tested. The results show that the 10kV hybrid DC circuit breaker can break 15kA short circuit current within 2ms, and has the characteristics of low loss and high reliability.

For 14 years, there were 23 trips that happened because of failure of the electromechanics switch after 2 years of installation which caused around Rp. 70 Million financial loss. In order to tackle this issue, installation of an electronics switch is proposed. The electronics switch is proposed because it has very same function with electromechanics, but it has better in terms of usability, performance, and cost effectiveness. To prove this a study on electronics switch usability, performance and cost effectiveness is required. To make this findings and solutions more robust, 14 years data from electromechanics switch (2 blocks if Combined Cycle Power Plant) and 10 years data from electronics switch is recorded. To compare both switches some parameters are introduced which are usability (power consumption, maintainability, and environment disturbance), performance (speed, lifetime, and integration), and cost effectiveness (investment, maintenance, and cost saving). From the result it shows that the electronic switch is better than the electromechanics switch.

As the need for green and effective utilization of energy continues to grow, the advancements in the energy and power electronics industry are constantly driven by this need, as both industries are intertwined for obvious reasons. The developments in the power electronics industry has over the years hinged on the progress of the semiconductor device industry. The semiconductor device industry could be said to be on the edge of a turn into a new era, a paradigm shift from the conventional silicon devices to the wide band gap semiconductor technologies. While a lot of work is being done in research and manufacturing sectors, it is important to look back at the past, evaluate the current progress and look at the prospects of the future of this industry. This paper is unique at this time because it seeks to give a good summary of the past, the state-of-the-art, and highlight the opportunities for future improvements. A more or less ‘forgotten’ power electronic switch, the four-quadrant switch, is highlighted as an opportunity waiting to be exploited as this switch presents a potential for achieving an ideal switch. Figures of merit for comparing semiconductor materials and devices are also presented in this review.

A new protection relay to detect, suppress and mitigate secondary ferroresonance in CCVTs is presented in this paper. The new protection relay uses frequency response characteristic to detect and characterized secondary ferroresonance and an electronic switch with back to back thyristor to introduce a commutable load to the CCVT’s secondary circuit for secondary ferroresonance suppression. The proposed protection relay has been verified with computer simulations and hardware experiments, which demonstrated a successful performance regarding three design aspects, namely, detection, suppression and security.

The features of the operation of an improved consumer power supply system with a pulsed power supply are considered. Special aspects of that system consist in the fact that the inductive load of the consumer is shunted by a semiconductor element, locked during the duration of the voltage pulse of the source and opened during a pause, meanwhile to the supply line, an electronic switch inserted, which opened during the voltage pulse from source and lockdown during a pause. It was proved that with such an algorithm of operation, the reactive energy of the inductive consumer provides an increase in its active power and decrease consumed current from the source.

Based on the problem of non-matching of protective characteristics before and after the use of solid-state power distribution, this paper proposes a stress assessment model in the short-circuit mode of solid-state electronic switch, and realizes the calculation method of transient junction temperature of power semiconductor devices in the short-circuit mode. The parasitic parameters and influencing factors of the solid-state power distribution circuit are analyzed based on the whole satellite state. The solution of the front and back level protection characteristics matching is given to ensure the safety of the solid-state power distribution aerospace application, which has a strong guiding significance and application value.

Electromagnetic disturbance(EMD) of the flexible DC converter station is mainly caused by the periodic turn-on and turn-off of the power electronic switch. And it will affect the secondary equipment in the form of conduction. In order to make the simulation results of the MMC electromagnetic transient model more accurate at high frequencies, it is essential to develop models of the valve over a wide frequency range. In this paper, the impedance characteristics of each passive component are measured. And established the component's wide frequency equivalent circuit through vector fitting and network synthesis. Then build wide-band models of active components based on engineering measurements. Stray parameters of the valve tower are calculated by the finite element method. Finally, a single-port MMC electromagnetic transient model based on the wide frequency characteristics is established. By studying the electromagnetic interference of the valve during operation, it can be seen that the ideal model has a large deviation at high frequencies. The construction of the wide frequency model of the converter valve has great engineering significance for the simulation of electromagnetic interference.

This paper proposes a new topology of three-phase split-source inverter (SSI) with only one auxiliary power electronic switch inserted into the three-phase full-bridge inverter. Split-source inverter is a single stage topology, which combines the boosting stage with the DC/AC converter stage. The proposed three-phase SSI has fewer passive components than impedance source converters (like ZSI). Switching states of the conventional three-phase VSI can be used with the SSI to control the output voltage. An independent control for both DC link voltage and output AC voltage is achieved using model predictive control. The DC link voltage can be controlled via duty cycle obtained by a maximum power point tracker or by fixed duty cycle as used in this paper. Simulation results show that the proposed control achieves low THD of the AC output voltage (good performance) with both normal loading condition and sudden load change condition.

In this paper, an AC-based agile parallel hardware system was introduced for ECT. A multi-frequency excitation and measurement strategy was proposed to minimize the switching time between different channels. For an ECT sensor with $2^{m}$ electrodes, all the mutual capacitances can be measured much faster, which is $m$ /( $2^{m}-1$ ) of the time used by the classical single-frequency excitation and measurement strategy. It implies that the proposed strategy accelerates the capacitance acquisition in an exponential way. Besides the efforts made to reduce the switching times between channels, the operating time of each electronic switch was selected to fasten the demodulation. The hardware fabricated here can be modified agilely by running codes, and different excitation and demodulation methods can be implemented on the chip. To verify the performance of the agile system, ECT sensors with different electrodes are facilitated to measure the mutual capacitances. The capacitances can be achieved with a frame rate of respectively up to 15.15 kilo frames per second (kfps) and 12.82 kfps in the cases of 12 and 16 electrodes. The ignition process of a flame generated by a Bunsen burner can be captured by the proposed system. Also, the discharging of the igniter can be imaged, and it is usually undistinguishable in a low-speed system.

At present, the automatic shutdown characteristic of the thyristor current zero-crossing point in the power electronic switch is mainly used to block the arc that may occur during the operation of the hybrid on-load tap-changer. The hybrid on-load tap-changer is an important part of the transformer, so studying the characteristics of the thyristor will help to increase the service life of the transformer. In this paper, the transient process of the floating potential and current and voltage of the gate-level contacts of the thyristor during the opening and closing process is studied. The thyristor selection of the on-load tap-changer provides a reference, which aims to improve the comprehensive performance and practicality of the on-load tap-changer.

The use of RF microelectromechanical systems (RF-MEMS) switches for the design of broadband modulated scattering techniques (MSTs) wireless sensors has been investigated in this letter. In an MST sensor, the antenna is loaded with different resistive loads to produce a modulation in the backscattered field by means of an electronic switch. At microwave frequency bands, the RF switches are quite expensive, moreover, they are quite narrowband. The narrowband behavior of MST sensors is one of their major drawbacks. The adoption of RF-MEMS microwave switches could be a good opportunity to overcome this problem. In particular, MEMS switches are able to perform good up to 110 GHz with a reduced dimension and complexity. In this letter, an MST sensor prototype based on MEMS switches and able to work in the whole X -band from 8 to 12 GHz has been designed, fabricated, and experimentally assessed. The obtained results are quite good and they demonstrate the feasibility of such kind of sensors. In particular, the MEMS switches demonstrate that they could play a key role for the design of millimetric and submillimetric frequencies bands MST sensors, where the standard microwave switches technologies cannot operate.

Utilization of microcontroller especially MCS-51 family has been widely implemented in various applications, such as control and telecommunications applications. One of them is the phase shifting array antenna in the telecommunication field. The Array Antenna was designed from some of dipole antenna. Each element at dipole antenna has a different phase and can be controlled electronically. The phase shifting was done using AT89S51 microcontroller that functioned as an electronic switch on the transmission cable connection. The phase of the array antenna will be moved without moving the structure of the array antenna itself, so that the direction of radiation pattern can be changed in accordance with the phase shifting between the antenna elements.

The optical control of atomic relocations in a metallic quantum point contact is of great interest because it addresses the fundamental limit of "CMOS scaling". Here, by developing a platform for combined electronics and photonics on the atomic scale, we demonstrate an optically controlled electronic switch based on the relocation of atoms. It is shown through experiments and simulations how the interplay between electrical, optical, and light-induced thermal forces can reversibly relocate a few atoms and enable atomic photodetection with a digital electronic response, a high resistance extinction ratio (70 dB), and a low OFF-state current (10 pA) at room temperature. Additionally, the device introduced here displays an optically induced pinched hysteretic current (optical memristor). The photodetector has been tested in an experiment with real optical data at 0.5 Gbit/s, from which an eye diagram visualizing millions of detection cycles could be produced. This demonstrates the durability of the realized atomic scale devices and establishes them as alternatives to traditional photodetectors.

Comparative experiments are performed on a semiconductor laser with different numbers (one or two) of emitting sections monolithically integrated with an electronic switch (thyristor). It is shown that the functional integration of a laser with a thyristor in one heterostructure makes it possible to achieve efficient operation of the laser in a pulsed regime (up to 50 W), while the use of vertical integration of two laser sections in this device additionally increases the optical output power to 90 W with all other conditions being the same.