Constant current controlled flyback converter is widely used in low power applications for its simple structure and low cost. In order to further improve the output power and the efficiency, active-clamp flyback converter with soft-switching technique is always used. To avoid the nonlinearity and temperature drift of opto-coupler in the feedback circuit, a constant current digital control method is

Presents the table of contents for this issue of the publication.

Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.

This letter proposes a new switching cell with switching frequency modulation (SFM) and resistive characteristic (voltage follower) for converters that are current-fed. Soft commutation and current null (when the diode blocks) are achieved with SFM and a fixed duty cycle for converters based on this switching cell. The operating principle, a mathematical analysis of the cell, and two topological variations

Integrated gate commutated thyristor (IGCT) has low loss, low cost, and high reliability in the application of modular multilevel converter (MMC). However, due to the special turn- off process of IGCT, the commutation transient is very different for IGCT in MMC. This letter reveals a current oscillation phenomenon of MMC based on IGCT and fast recovery diode (FRD). Especially, this oscillation effect

In wireless power receiver systems, the buck converter is widely used to step down the higher rectified voltage derived from the wireless receiver coil, to a lower output voltage for the immediate battery charging process. In this article, the presence and effect of the right-half-plane (RHP) zeros found in the small-signal inductor-current-to-duty-ratio and output-voltage-to-duty-ratio transfer functions

We introduce a novel electromagnetic interference suppression method based on the piezoelectric effect for switch-mode power supplies (SMPSs). A piezoelectric interference-suppression component (PISC) generates a low-impedance propagation path for conducted emissions at its resonance frequency. This results in an attenuation of a discrete disturbance peak. Besides the resonance frequency, the PISC

Parallelization of silicon carbide (SiC) metal-oxide-semiconductor field-effect transistor (MOSFET) could significantly improve the current capability and power rating of power converters. However, the inductive coupling effect of parasitic inductance between the paralleled branches is a critical challenge for the mathematical modeling of electromagnetic interference (EMI) in a power module with parallel-connected

An extended sliding mode observer (ESMO) with Hurwitz-based power reaching law (HPRL) is proposed in this article to improve the performance and the robustness of predictive current control (PCC). First, extended state-space realizations of permanent magnet synchronous motor (PMSM) stator currents mathematical model are introduced by incorporating parameter mismatches as lumped disturbance and state

The dc-side admittance of a modular multilevel converter can be used in assessing the stability of the dc system by means of impedance-based stability criteria. An accurate mathematical representation of the small-signal admittance can be given using harmonic linearization. To this end, the effect of the internal dynamics of the converter, e.g., the circulating current, the converter control scheme

Microgrid (MG) technologies facilitate reliable, efficient, and economic operation of distributed resources such as photovoltaic and battery storage systems. The well-known droop method controls different sources in an MG to properly share power supply. However, utilizing the droop method poses two major challenges. First, while the droop method can prevent converter overloading, it cannot protect

The underlying voltage/current tracking control is a key issue for a hybrid energy storage system (HESS) in electric vehicles. This article presents an innovative passivity-based L2-gain adaptive robust control (L2-ARC) method for a fully active battery/super-capacitor HESS. First, by exploiting and analyzing the internal structural properties, the port-controlled Hamiltonian model with dissipation

Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.

Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.

It is well known that there is the commutation interference pulse in zero-crossing points (ZCPs) of back electromotive force (EMF) for brushless direct current (BLdc) motors. Generally, the interference pulse is handled by a low-pass filter (LPF) with a low cutoff frequency. However, the phase delay caused by LPF will deteriorate the performance of BLdc motors. In this letter, a novel phase-delay-free

Active power decoupling circuits are used in bidirectional single-phase grid-connected systems to enhance the circuit lifetime by creating an alternative path for the typical dc-side power pulsating ripple. Therefore, this reduces the requirement of smoothing dc capacitors allowing compact designs even with the implementation of long life metalized film technology. However, with the necessary addition

Given the high complexity of the conventional three-level space-vector pulsewidth modulation (3L SVPWM), simplified SVPWM algorithms are usually adopted instead. However, existing simplifications for 3L SVPWM still have a large computation burden, which limits its applications, e.g., in high-switching-frequency silicon-carbide converters with a short computation period. In this letter, based on a typical

Since dc distribution minimizes the number of power conversion stages, it lowers the overall cost, power losses, and weight of a power system. Critical systems use IT grounding because it is tolerant to the first-fault. Hence, this is an attractive option for hybrid electric aircraft (HEA), which combines gas engines with electric motors driven by power electronic converters. This letter proposes an

Simultaneous over 40-W electric power and optical data transmission using an optical fiber is demonstrated for optically powered remote antenna units in future mobile communication networks. In this article, to further increase the delivered electric power by power-over-fiber link using a double-clad fiber, we improve the link design to extract a higher feed light power from the double-clad fiber output

Reduced power processing is a new trend to improve the conversion efficiency of light-emitting diode (LED) driver systems. Based on the concept, a new LED driver architecture is proposed in this article, which requires fewer power semiconductors compared with prior works, leading to the potential of lower cost and higher efficiency. A new ac/dc LED driver topology is derived accordingly based on the

The series and parallel multicell converters have been introduced because they provide benefits in terms of efficiency and power density. However, they also allow reducing the amount of energy stored in the filters, which potentially allows for faster dynamic responses. Interleaving the control patterns of different cells is another distinctive feature of these converters and is also the root of another

The maximum boost control (MBC) technique of voltage boosting offers the highest output voltage gain among other boost control techniques of Z -source inverter (ZSI). But, this technique suffers from the major drawback of sixth fundamental frequency (6 th F1) ripple components of the impedance network inductor current. Due to this, the size/cost of the impedance network increases, which limits the

In this letter, direct power control (DPC) of rotor-tied doubly fed induction generator (DFIG) is presented for the first time. First, a theoretical study is presented to acknowledge the fundamentals of DPC of rotor-tied DFIG. Thereafter, two rotor position-sensorless algorithms (RPSAs) are presented to eliminate the need of rotor position sensor. The RPSA-I is developed using the mathematical model

The LLC resonant converter is a popular, variable switching frequency dc--dc converter that may be controlled using two methods: charge and frequency control. In this article, the application of LLC resonant converters to input-parallel, output-parallel system is studied. In this respect, the models of output-port I-V characteristics and small-signal output impedance of the charge controlled LLC converter

Faults in aluminum electrolytic capacitors (AECs) are classified as the major cause for power electronics equipment breakdown, mainly due to AECs wear out through the vaporization of the electrolyte, as a result of both aging and temperature effects. The majority of manufacturers identify the end-of-life threshold of such capacitors as their equivalent series resistance (ESR) increases by 80% or their

Space vector modulation (SVM) strategy is widely used in two-level and three-level converters because of its advantages. However, the sector triangles, switching states, and switching sequences increase dramatically as the number of levels increases, which makes it difficult to implement the SVM algorithm in industrial applications of high-voltage and high-power multilevel converters. To extend the

Recent applications of modular multilevel converter (MMC) have posed various problems such as ac/dc grid faults, asymmetric operation conditions, ac grid voltage excessive harmonics, and ac circulating currents, which deteriorate the system's performance and also threaten the safe operation. In this article, an improved comprehensive control architecture of MMC is proposed to maintain a stable voltage

The commonly used average model is not applicable to predict the stability performances of constant on -time (COT) controlled buck converters. It has been reported that the issues of stability can be addressed by using the control signal to output voltage transfer function of the converters, named G VC , for such class of converters. G VC can be mathematically derived using describing-function approach

Adjustable dc-link voltage operation is an attractive solution to improve the overall efficiency of electric vehicles (EV s ). This article proposes a dual-port inverter (DPI) with an internal dc–dc conversion system for the adjustable dc-link operation of the EV s . Unlike the conventional two-stage structure, the DPI provides a power flow path from the battery to the inverter directly. Hence, the

Similar to other power semiconductors, gallium nitride enhancement-mode high-electron-mobility transistors (GaN E-HEMTs) require short-circuit protection (SCP) or overcurrent protection (OCP) in practical applications. However, the fast-switching characteristic of GaN introduces the challenge to the protection. For SCP, the traditional methods are either too slow or not practical for GaN. Therefore

Critical conduction mode (CrCM) active clamp flyback (ACF) converter is regarded as a good candidate to be applied in high-frequency small power supplies. This article focuses on the modeling, analysis, and controller design of CrCM-ACF converter. The small signal model of the converter is derived based on a zero-input resonant equivalent circuit and extended describing function (EDF) method for the

LLC resonant converter is one of the most popular isolated dc/dc converters owning to its advantages of simple control, wide voltage gain regulation capability, and soft switching operation. Nevertheless, high efficiency and high power density are always the goals for LLC converters. To further increase the conversion efficiency, the synchronous rectification (SR) technology is adopted, where the uncontrolled

The inherent frequency of magnetic coupling resonance based wireless power transfer system (MCR-WPT) is up to the level of kHz or even MHz. The class-E converter with zero-voltage switching (ZVS) could eliminate the considerable switching loss, however, the high voltage stress and sensitive ZVS condition to coils distance limit its application seriously in MCR-WPT. To solve the issues, a voltage-clamped

This article presents a bidirectional nonisolated dc–dc converter based on switched-capacitor converters intended for electric railway system applications. It consists of plural main converters with two power devices per converter, plural auxiliary converters each of which is formed by cascaded chopper cells, and small-sized inductors for current control. The dc–dc converter can achieve zero-current

In this article, a novel high-reliability single-phase dual-output current source inverter is presented. By using the switching-cell (SC) structure in the proposed topology, the overlap-time between switching transition can be minimized or eliminated. This improves the quality of ac output currents, efficiency, and dc-source utilization. Additionally, the capacitors in SC structure can help to reduce

This article presents a low-complexity digital low-dropout regulator (DLDO) design featuring a novel voltage regulation and transient enhancement scheme, and a charge-redistribution-based ripple suppression (CRRS) technique that smooths output by redistribution of excessive energy via a small capacitor. Also proposed is a fast-turnaround general DLDO design approach comprising a hybrid discrete-continuous

This article studies a dual inverter supplied by a dc-link and a floating capacitor (FC), emerged as a promising inverter topology for motor drive applications. For this type of inverter, the voltage ratio between the dc-link and the FC can be actively controlled. This ratio design is crucial as it essentially defines both the dc-link voltage utilization and the inverter output quality. Several voltage

In this article, we present a bridgeless hybrid-mode Zeta inverter for distributed energy systems. We integrate the secondary diode of the conventional unfolding-type Zeta inverter into one of diagonal pairs of the secondary-side switches in a bridgeless Zeta inverter. This structure decreases the number of active power components and provides naturally well distributed loss at the body diodes of the

To improve the input current total harmonic distortion (THD), the look-up table (LUT) method is used in the 360–800 Hz critical conduction mode (CRM) boost power factor correction (PFC) converter. When the ac line frequency changes drastically and suddenly, the zero-crossing detection method needs the half ac line period to follow the sudden frequency jump, causing a mismatching between the LUT and

This article investigates the modeling and control of brushless doubly fed induction generator (BDFIG) under an unbalanced network. The system behavior of BDFIG under the unbalanced grid voltage is analyzed. The control strategies and different control targets of BDFIG in balanced and unbalanced networks are discussed. In order to achieve control targets, a current control strategy consisting of a

An envelope tracking supply converter was presented for the RF power amplifiers of sub-6 GHz 5G NR mobile devices. The hybrid supply converter consisted of a linear, fast switching, and slow switching regulators connected in parallel. The two-phase hysteretic control was proposed for use in the fast switching regulator to track the fast-varying envelope of 40-MHz 5G NR signal. The 0.25-μm CMOS supply

A novel sliding-mode-based extended state observer (SMESO) is proposed to improve the disturbance rejection ability and enhance the dynamic performance of permanent magnet synchronous motor drive systems. First, an extended state observer based on the fast terminal sliding-mode control (FTSMC) method is developed for better comparison, which can improve the robustness against load disturbances, finite

In the open-winding permanent magnet synchronous motor (OW-PMSM) system fed by dual inverter with common dc bus, suitable control strategy should be adopted to suppress the torque ripple generated by the third harmonic flux and 0-axis current. However, the mathematical model will change when the motor is under open-phase fault so that the coordinate transformations and control strategy should be redesigned

This article first investigates the equivalent parallel capacitance (EPC) and equivalent parallel resistance (EPR) due to the electromagnetic field inside the Mn-Zn ferrite toroidal cores of the inductors with a single-layer winding based on electromagnetic theory. From the investigation, the effects of core's cross-sectional shape and number of winding turns on the EPC and EPR are explored. A stacked

The third-harmonic injection two-stage matrix converter (3TSMC) not only possesses the advantages of a TSMC, but also enhances the input reactive power control capability. Due to the input current deviation caused by the voltage ripple across the input filter capacitors, the mains currents of the 3TSMC are distorted at sector boundaries. To improve mains current quality, this article proposes a mains

The efficiency of wide-bandgap (WBG) power converters can be greatly improved using high-frequency modulation techniques. This article proposes using single-loop and double-loop hexagonal sigma-delta (H- $\Sigma \Delta$ and DH- $\Sigma \Delta$ , respectively) modulations for voltage source converters (VSC) that use silicon carbide (SiC) semiconductors. These allow high switching frequencies to operate

This letter proposes a generic method to model and mitigate the transient dc bias in the transformer winding current and the magnetizing flux linkage of the dual-active bridge (DAB) converter, which is valid for all the most commonly used modulation methods such as single phase-shift, extended phase-shift, dual phase-shift, and triple phase-shift. By performing a simple dynamic volt-seconds balancing

The application of established test routines like power cycling to wide bandgap devices may be not as straightforward as it seems: When power cycling silicon carbide MOSFETs, the original purpose of triggering package related degradations under application-like and accelerated conditions might be influenced by device related changes during the test, such as carrier trapping, which may lead to a shift

The synchronized multiple bias-flip (SMBF) interface circuits enhance the piezoelectric energy harvesting (PEH) capability by maximizing the extracted energy from the piezoelectric source and simultaneously minimizing the dissipated energy in the power conditioning circuit. They provide the most energy-economic solution for the piezoelectric energy harvesting enhancement. However, the growing scale

Compared with traditional frequency limitation method DCM and QCFTCM for TCM-based inverter, this article proposes a hybrid TCM method, which can achieve both full range ZVS and frequency variation limitation. An accurate resonant transition model is established and the switching frequency variation range can be obtained for TCM. The hybrid control can be implemented according to the variation ratio

The control flexibility of the power inverters that interface distributed generation can be exploited to incorporate power quality enhancement features in addition to the usual power management control. This article presents a novel control scheme that achieves voltage balance at any node of an ac microgrid regardless of the impedance value of the power network. The collaborative strategy is devoted

For power electronic converter systems, the cost and the size of the magnetic components are typically limiting factors when it comes to overall production costs and power density. This especially holds for soft-switching high-frequency applications, where a resonant discharge of the output capacitances of the semiconductors relies on sufficient amount of energy stored in the main magnetic components

In this article, a universal power flow model for the dual active bridge (DAB)-based dc–dc converters with phase-shift modulation is derived. The model considers the lossy components, the dead time, and the resonant commutations of the converters. A power flow model for the partial parallel dual active bridge (P $^{2}$ DAB) converter is generated from the universal power flow model. Based on the calculations

This article presents a digital V 2 constant on -time control buck converter with adaptive voltage positioning (AVP) and automatic closed-loop output impedance ( Z oc ) calibration for advanced system-on-a-chip processors. To ensure that the output voltage deviation remains within the desired range, the system is equipped with AVP. For an optimal AVP design, the system includes a second-order digital

The bidirectional LLC resonant converter operated at fixed switching frequency is a preferable candidate for a true dc transformer that does not actively control the power flow. This is due to its naturally stiff voltage ratio regardless of the imposed load, its low switching losses, and a stable open-loop behavior. However, in the open-loop operation, determining the required operation direction of

This article presents the analytical modeling of synchronous class E rectifiers with the load-independent operation, which achieves zero-phase-angle input impedance, soft-switching over the entire load range with a constant voltage gain. The optimal design of the synchronous class E rectifier is proposed to realize both zero-voltage-switching turn- on and zero-current-switching turn- off at the expected

Split-source inverter (SSI) has been proved to be an attractive single-stage dc/ac converter for its compact structure, continuous input voltage, and input current. However, due to the coupling of the boost stage and the inverter stage, SSI suffers from the low dc-link voltage utilization problem, which will increase the system cost and switching losses. To break through this inherent limitation, this

This article presents a comprehensive analysis of torque ripple and power factor for three-phase mutually coupled switched reluctance motors (MCSRMs) with sinusoidal current excitation. MCSRMs controlled by sinusoidal currents have the advantage of using the conventional voltage source inverter and the conventional vector control. However, MCSRMs are characterized by high torque ripple and low power

Making electrical driving systems cheaper, lighter, and more reliable is the consistent pursuit of current research and development. Mono-inverter multipermanent magnet synchronous motor systems tend to share the static converters in electromechanical systems by connecting machines in parallel. This type of system has an obvious advantage in overall weight and cost. In this article, we have proposed

The conventional active neutral-point-clamped (ANPC) inverter inherits excellent high-frequency common mode voltage (CMV) mitigation ability but with a restricted voltage gain. This letter proposes a novel five-level ANPC inverter that is able to accomplish voltage-boosting within a single-stage dc–ac power conversion. A common ground in the proposed topology not only mitigates the high-frequency CMV