A polarization‐independent reconfigurable frequency selective rasorber (FSR)/absorber with low‐insertion loss (IL) based on diodes is proposed in this article. The presented structure consists of a lossy layer based on square loops and a bandpass frequency‐selective surface. These two layers are separated by an air layer. Each layer has an embedded bias network that provides the bias voltage to the

In this paper, a WR‐1.5 band (500–750 GHz) 3rd order waveguide bandpass filter has been designed and fabricated using high precision computer numerically controlled metal micromachining. The filter has been measured with a 7.29% (48.7 GHz) bandwidth at the center frequency of 667.5 GHz. The minimum passband insertion loss is measured to be 0.87 dB and the measured return loss is better than 10 dB across

In this research, a highly efficient single‐layer reflective polarization converter based on anisotropic metasurface is proposed for microwave communications. The periodic design works in a dual‐operation mode as a half‐wave plate (cross‐polarizer) and a quarter‐wave plate (circular‐polarizer) over multiple frequency bands. The unit‐cell is comprised of coupled D‐shaped resonators printed on a low‐cost

This article presents the multiband asymmetric radio frequency (RF) to direct current (DC) converter circuit for the wireless power transfer (WPT) applications. The proposed circuit is composed of a power divider, novel asymmetric multiband matching circuit and RF Schottky diode quadrupler voltage rectifier circuit. Unlike the conventional narrow band quadrupler using two Greinacher cells with opposite

Photonic signal processing is a suitable alternative of electronics based processing for wideband frequency detection. We propose a novel technique for the detection of a wide range of frequencies based on photonic signal processing. The unknown frequency to be measured is used to modulate a tunable optical source by implementing single sideband suppressed carrier modulation. The modulated signal is

This letter shows that the synthesis of coplanar waveguides with finite substrate thickness can be obtained by simple numerical solution from the exact quasi‐static formulae of the characteristic impedance using bisection method The novelty of the method is that accurate synthesized values compared to those from curve fitted formulae are obtained. Moreover, sophisticated numerical techniques are not

A new local current-based fast high impedance fault (HIF) detection scheme for DC microgrid clusters using mathematical morphology (MM) is proposed in this paper. The proposed strategy consists of two MM based parts. The first part is MM erosion filtering to extract the current signals and its components to extract the differential feature vector. The second part is MM regional maxima, for defining

Orthogonal Frequency Division Multiplexing (OFDM) is the one of the most preferred multiplexing technique for realizing high-speed wireless communication, like Long Term Evolution (LTE) and LTE-Adv. In the era of digital wireless communication, applications of wavelet theory have been favorably applied in many areas of signal processing. Orthogonality, flexible time-frequency analysis, and the ability

A DLP (data loss prevention) system usually arranges network monitors at the network boundary to perform network traffic capture, file parsing, and strategy matching procedures. Strategy matching is a key process to prevent corporate secret-related documents from leaking. This paper adopts the document fingerprint similarity detection method based on the SimHash principle and customizes the KbS (Keyword-based

Just noticeable distortion (JND) is widely employed to describe the perception redundancy in the quantization-based watermarking framework. However, the existing JND models are generally constructed to treat every region of the photograph with an equal focus level, whereas the defocus effect has never been considered. In this paper, the defocus feature, which can portray the aesthetic emphasis in the

An experimental investigation was carried out to investigate Particulate Number (PN) emissions from a modern, small-capacity Gasoline Direct Injection (GDI) engine. The first part of the study focused on improving measurement repeatability using the Cambustion DMS-500 device. Results showed that sampling near the exhaust valve – while dampening the pressure oscillations in the sampling line – can significantly

Homogenous charge compression ignition (HCCI) combustion is a low temperature combustion process which combines high combustion efficiency with ultra-low NOx raw emissions. Steep increases of the in-cylinder pressure and unstable combustion sequences at the limits of the operating range can damage the engine and limit the use of HCCI to part load operation. This can be done using closed loop combustion

This work presents the development of a model to capture the NOx sensors cross sensitivity behavior based on NOx sensor cell temperature, as well as a model do predict the slip of the NOx and NH3 after the SCR catalyst, as a way to reduce the error in the exhaust emissions estimation needed for feedback SCR control strategies. The emissions prediction model is based on the different cross sensitivity

A fully mechanized coalface is a rugged environment that has poor visibility. The traditional video monitoring system has problems such as a lack of realism, a blurry monitoring effect, and poor reliability. It is an important task to monitor the operations of the three-machine equipment (we will refer to the shearer, hydraulic support, and scraper conveyor as the three-machine equipment) intuitively

IoT system becomes a hot topic nowadays for smart home. IoT helps devices to communicate together without human intervention inside home, so it is offering many challenges. A new smart home IoT platform powered using electromagnetic energy harvesting is proposed in this paper. It contains a high gain transmitted antenna array and efficient circularly polarized array rectenna system to harvest enough

This paper reports a deep‐ultraviolet LED (deep‐UV‐LED) package based on silicon MEMS process technology (Si‐PKG). The package consists of a cavity formed by silicon crystalline anisotropic etching, through‐silicon vias (TSVs) filled with electroplated Cu, bonding metals made of electroplated Ni/AuSn and a quartz lid for hermetic sealing. A deep‐UV LED die is directly mounted in the Si‐PKG by AuSn

A differentially fed dual-polarized antenna with low cross-polarization is proposed for sub-6 GHz applications. The main patch is fed through two pairs of symmetrical ports, and annular-ring slits are etched around the feedings. The broadband 180° phase shifter provides a stable differential feeding structure, and a 1 mm thick radome with a parasitic patch printed on its inner surface is utilized to

The integration of Distributed Generators (DGs) in the reconfigurable microgrid is evolved to enhance the power delivery performance. The DGs are categorized as controllable and uncontrollable based on their power generation control behaviors. In addition to the control behavior, under the uncertain conditions of the microgrid, the performance of DGs is limited due to their respective drawbacks. Therefore

This paper presents the design and validation of a new adaptive variable gain reaching law, integrated with sliding mode control (SMC), to control perturbed and unperturbed nonlinear systems. The novelty behind this law stems from its capability to overcome the main limitations involved with SMC. In contrast to existing reaching laws, system’s performance can be substantially enhanced via this law

Ash sintering and fusion characteristics are closely associated to ash-related issues. The effects of peanut hull (PH) ash on the initial sintering and fusion temperatures of high melting coal (Jiaozuo coal (JC) and Huolinhe coal (HC)) ashes were investigated. The formations of anorthite and adularia were responsible for the initial sinterings of JC and HC ashes, respectively. The increasing PH ash

This study presents a reduced switch three-phase three-level H-Bridge-based shunt active power filter (SAPF) for the mitigation of current harmonics, the reduction of current unbalance and the injection of reactive power. This recommended SAPF is developed by using two H-bridge and two DC-link capacitors. Compared to the conventional three-level H Bridge-based SAPF, the eight-switch cascaded H bridge

The mutual inductance between the primary and secondary coils is an important parameter in the wireless power transfer system, and the mutual inductance calculation of coils in many complicated circumstances has been studied. However, the mutual inductance calculation of two circular coils in arbitrary relative position with magnetic tiles have not been solved. In this study, an analytical formula

A conventional pulse frequency modulation (PFM) controlled LLC resonant converter requires a wide switching frequency operating range to regulate the output voltage. There are some disadvantages of PFM LLC resonant converters: (i) the design and optimisation of magnetic components and gate driver circuitry are challenging; (ii) due to the variable switching frequency operating range, electro-magnetic

A zero voltage switching (ZVS) interleaved high step-up converter with coupled inductor and built-in transformer voltage multiplier cell is introduced in this study. A more flexible design is provided by increasing the voltage conversion ratio by utilising the turns ratios of the coupled inductor and built-in transformer. The ZVS operation of the metal-oxide-semiconductor field-effect transistors (MOSFETs)

This study presents the full-bridge dc–dc converter (FBDC) operated with customised pulse width modulation (cPWM) for electric vehicle (EV) battery charging. The proposed cPWM retains all the benefits of the popular conventional phase shifted modulation (PSM) with minimal modification in the pulse width while further achieving the zero voltage switching for the active switches of the converter. The

In order to construct the voltage-sourced converter high-voltage direct current grids, the high capacity direct current circuit breakers (DCCBs) are in demand. The hybrid DCCB has been the mainstream proposal, where the high-voltage solid-state switch (HVSS) is the key component for breaking the final fault current. Investigating the current commutation between the breaking branch and energy-absorbing

A three-phase pulse-width modulation (PWM) rectifier can usually maintain operation when open-circuit faults occur in insulated-gate bipolar transistors (IGBTs), which will lead the system to be unstable and unsafe. Aiming at this problem, based on random forests with transient synthetic features, a data-driven online fault diagnosis method is proposed to locate the open-circuit faults of IGBTs timely

Model predictive power control (MPPC) is considered as a promising algorithm utilised in grid-connected inverter due to its fast dynamic response, simple control structure and multi-objective optimisation. However, under unbalanced network, the grid current with excessive distortion troubles the application of MPPC. Based on the conventional MPPC, this study proposes a model predictive flexible power

In this study, an advanced predictive control system is proposed which consists of two cascade predictive controllers; the first one minimises the power losses while the second one minimises the torque ripple. In the first controller, motor losses are formulated as a function of stator-flux linkage components. Then, the optimal stator-flux linkage vector which causes the minimum losses is found by

Although the control strategy regarding quasi-Z-source inverter (qZSI) has been widely studied, the dynamic response and steady-state accuracy of the system with a non-linear section should be further improved. Based on this, this study proposes an energy shaping control (ESC) method based on the port-controlled Hamiltonian (PCH) model for qZSIs. Firstly, based on the average state-space model, the

This paper depicts a self-tuning adaptive control method along with a novel robust procedure to system identification which is applied to a single-phase full-bridge Inverter with LC filter by Pulse Width Modulation (PWM). Moreover, an LC filter is designed to decrease the disturbing harmonics produced by PWM which, the stability of the filter can be noted as an important issue. On the other hand, a

This study reveals the energy shaping port-controlled Hamiltonian passivity-based control (PCH-PBC) technique for an interleaved boost power factor correction (IBPFC) converter. First, the mathematical modelling of an IBPFC converter is developed under all possible operating modes. Then, the average state-space model of the system is established with the help of averaging state-space technique. Further

In this study, a comparative evaluation of a family of isolated Ćuk DC/DC converter with step-up techniques is presented. The voltage gain techniques are the reduced redundant power processing and the voltage multiplier. In addition, a detailed comparative analysis of the converters is showed. This comparison comprises features, such as the principle of operation, voltage gain curves, voltage and current

The design of the control system in an inverter-based microgrid (μGs) is a challenging problem due to the large number of parameters involved. Different optimisation methods based on obtaining an approximated mathematical model of the μG can be found in the literature. In these approaches, the non-linearities and uncertainties of the real system are typically not considered, which may result in a non-optimal

This study presents robust parametric methods for the detection and estimation of grid-connected issues such as islanding, harmonics, and interharmonics. The power system signals are time varying owing to the intermittent nature of renewable energy sources. IEEE and IEC consider signals as stationary, which are negated in a future scenario. Therefore, parametric methods need to be applied for the estimation

In this study, a non-isolated high gain DC–DC converter is presented. The proposed converter yields a voltage conversion ratio value which is a cubic function of the voltage gain obtained from a boost converter. The proposed converter is synthesised by judiciously interfacing a two-phase interleaved boost converter with voltage-lift capacitor and a quadratic boost converter. Resultantly, the proposed

This work deals with the control law design and experimental verification of a grid-forming dispatchable distributed generation based on a back-to-back converter. The proposed system brings several improvements to the prime mover as well as to the microgrid voltage quality. The control strategy is based on an inner current and an outer voltage loop for both sides of the converter. The external loop

In a photovoltaic array (PVA) tied grid system, PVA and the grid are connected at AC bus (ACB) to feed the power to the grid and the load connected locally at the ACB. The photovoltaic energy conversion system (PVECS) requires an improved dynamic controller to control the grid voltage harmonics under variable solar power and nonlinear unbalanced load conditions. The conventional filtering controllers

The Cauer thermal network has made a realistic physical representation of thermal behaviour of a multi-chip module (MCM) theoretically possible. However, the traditional method assumes the heat conduction is critical, with an approximate one-dimensional heat conduction path for calculation and fixed heat spreading angle to make up for the compensation brought by the approximation. It will limit the

A new non-isolated high-voltage gain single switch quadratic modified single-ended primary-inductor capacitor (SEPIC) DC–DC converter is proposed in this study. The proposed converter consists of a modified SEPIC converter along with a boosting module to obtain a high-voltage gain at a low-duty ratio. It has all advantages of the SEPIC converter such as continuous input current, which makes it applicable

Conventional switching table-based direct power control (DPC) usually suffers from higher power ripples due to the heuristic nature of the switching table. This study presents a novel model predictive DPC (MPDPC) strategy for grid-connected three-level inverters. In the proposed MPDPC strategy, a new synchronous frame-based predictive model is first developed and the conjugate of the complex power

To charge the battery of electric vehicles (EVs), inductive power transfer (IPT) system has been considered to be more appropriate than traditional plug-in system especially for its security and convenience. This study proposes a hybrid IPT system for EVs charging applications adopting one transmitter coil with series compensation and two receiver coils with series compensation and LCL compensation

This study presents active switched passive network-based high-gain DC–DC converters. The active switched network is formulated using two inductors, one capacitor and two diodes. Hence, the network is named as a 2L–C–2D network. Using ten components, an asymmetric high-gain DC-DC converter is proposed. This converter achieves a gain of 29 at an 80% duty ratio. In the asymmetric converter structure

This work proposes a cost effective with a compact power electronic interface for plug-in electric vehicles (PEVs), which has the ability to achieve the all modes of vehicle operation, including plug-in charging, propulsion (PR) and regenerative braking (RB) for on-board applications. The proposed converter for PEVs has minimum component count as well as step-up and step-down operation ability depending

This study presents a concept of modulation of a single-phase seven-level neutral point clamped (NPC) converter with natural DC-link voltage balance and symmetrical DC-link capacitors discharge. The method is analysed in a single-phase full-bridge inverter composed of four-level diode-clamped legs (4L-FBCLD) which utilises three capacitors in a DC-link. Under the classic pulse width modulation (PWM)

The active clamp flyback (ACF) converter utilising gallium nitride (GaN) devices with high-switching frequency and high efficiency is impressive in system miniaturisation for AC–DC adapters. Owing to poor reverse conduction of GaN devices, the improper dead time between two switches can cause large power consumption in high frequency. This study proposes a dynamic dead time optimisation technique for

Three-port isolated dc–dc converter, as an active exploration and trial of photovoltaic access to dc distribution system, has the advantages of superior control flexibility and high reliability. Due to the changes in the phase-shift (PS) angle, the conventional PS control method cause transient dc bias in inductor current and magnetisation current, further increasing the current stress of switches

This work introduces a novel non-isolated boost DC–DC converter with high-voltage gain and high efficiency. The magnetic coupling and voltage lift circuit technique has been utilised to enhance the voltage conversion ratio. In order to decrease the peak voltage across the active switch, the voltage lift circuit acts as a clamp circuit. The zero current switching in the OFF-state and the zero voltage

This study presents a solar photovoltaic (PV)-battery-integrated multi-input converter (PBMIC) based two-stage off-grid system for catering household ac appliances in areas where the grid is not available. The proposed single-stage PBMIC facilitates the control of both PV array and the battery along with adequate voltage boosting by employing only two controlled switches. This reduces cost for semiconductor

Three-phase passive (or uncontrolled) rectifiers are typically placed at the front end of the overall power conditioning circuit for AC to DC conversion in low-cost, small-scale renewable-energy systems, e.g. residential purposes wind turbines. Whenever a diode in one leg or multiple legs becomes faulty, offering an open circuit to the flow of current in both directions, it severely affects the power

Parasitic capacitances in transformers consist of three main groups: winding-to-winding, layer-to-layer, and stray capacitances. Stray capacitance is also made of turn-to-turn and turn-to-core capacitances. This study presents a novel analytical method for calculating the values of turn-to-turn, turn-to-core, and stray capacitances in each winding, and employs the results to calculate the equivalent

This article compares the humidity sensing performance of microwave sensors coated with a poly(methyl methacrylate), poly(2‐hydroxyethyl methacrylate), or poly(vinyl alcohol) (PVA) polymer. A microwave sensor based on a modified interdigital‐capacitor‐shaped defected ground structure (IDCS‐DGS) in a microstrip transmission line with enhanced permittivity sensitivity was designed on an RF‐301 substrate

Compact microstrip bandpass filters using triple‐mode resonator are investigated in this paper. At the center frequency of 2.45 GHz, a half‐wavelength microstrip open‐circuited resonator is loaded with a chip capacitor and a chip inductor to realize the triple‐mode resonator. By adjusting the resonator's parameters, the first three resonant mode frequencies could be tuned for bandpass filters with

Two decoupled antennas, comprising two feeding monopoles and one dipole shared by the monopoles, for the fifth‐generation (5G) multi‐input multi‐output (MIMO) applications are proposed. The feeding monopoles are placed on both sides of the coupled‐fed, common dipole. First, to operate in the 3.3–5.0 GHz 5G wideband, two resonant modes at about 3.6 and 4.7 GHz, contributed to by the common dipole and

This paper presents 28 GHz GaAs front‐end IC for 5G beamforming systems with single positive supply voltage. A 28 GHz front‐end IC consists of a 3‐stage power amplifier, a 3‐stage low noise amplifier and two reflective type single pole double throw switches in 0.15 μm enhancement‐mode (E‐mode) GaAs pHEMT technology. The proposed 28 GHz front‐end IC is controlled only with single positive supply voltage

The transient characteristics of the bipolar short-circuit fault on a loop DC distribution network with blocking converters are studied in this paper. A protection principle based on the integrals of the line differential current is proposed after analyzing the characteristics of the line differential current during an internal fault and an external fault. The protection criterion and setting method

Solar photovoltaics in electricity distribution networks is often limited by the rise in voltage magnitude. The pre-connection voltage magnitude is an important factor that determines the hosting capacity. This paper studies to which extent details of the pre-connection voltage magnitude impact the hosting capacity. Extensive measurements of voltage magnitude and solar power production were obtained

Integration of a group of distributed generators (DGs) and loads in the form of a microgrid (MG) enhances the supply reliability, reduces the amount of greenhouse gasses (GHG) emission, and reduces the generation cost. However, this integration requires a refined energy management system (EMS). The MG-EMS dispatches the power between DGs to optimize either of the generation cost, the amount of GHG

This paper presents a hierarchical coordinated volt-var controller (VVC) at medium voltage level for the containment of voltages at the critical nodes in a smart distribution network. VVC finds the optimal set-points for distributed generators and tap position of the transformers in order to contain the voltage at the critical nodes with-in limits and to minimize the total reactive power dispatched