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.

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.

The discontinuous conduction mode (DCM) is usually studied in single-diode and single-inductor converters, where only one DCM exists. However, multiple DCMs can appear in multidiode and multi-inductor topologies and the methodology to identify and characterize these multiple modes is not evident. In this article, a general method to study multiple DCMs is presented. The first step of the method consists

A high-performance electrical drive with a permanent magnet synchronous motor (PMSM) should ensure superior dynamic properties, reasonable load torque compensation, and robustness against parameter variations. The performance investigation related to the dynamic properties is usually made using the step response indicators and integral performance indexes. The robustness evaluation is more complex

Regulated constant power loads present an incremental negative input impedance that can destabilize the interconnected system. With ac, power-factor corrected (PFC) constant power loads, instabilities can arise from a dynamic instability between the source and load impedance. The dynamics involving a rectifying interface are nonlinear and evade classical impedance and stability analysis. Several efforts

With the gradually decreasing cost of high-performance digital processors, multisampling current control is a potential method to reduce the control delay and improve the stability in LCL-filtered grid-connected converters. In the practical implementation, an antialiasing filter is required to remove the sampled switching harmonics and suppress the low-order aliasing. However, due to the phase lag

High-power isolated dc–dc converters are preferred in the medium-voltage cascaded H-bridge (CHB) photovoltaic (PV) generation systems due to high power density and galvanic isolation. However, high-power transformers in dc–dc converters can result in high power losses and poor heat dissipation due to thick isolation materials. The three-phase LLC (3P-LLC) converter has been reported suitable for high

This article proposed a frequency regulation strategy (FRS) to realize zero voltage switching (ZVS) in the dynamic process of LCC-S wireless power transfer systems, which aims at suppressing serious switching noise in the starting-up phase of the inverter. By detecting the magnitude and direction of the output current of the inverter, a delayed turn-on signal is timely applied to ensure that the inverter

The elimination of periodic torque disturbance in permanent magnet synchronous machine (PMSM) drives is a multifrequency control task, and adding resonant parts to the controller has an impact on the robustness of the system. This article aims to address the torque-ripple reduction in PMSM drives for smooth speed control, where an extended harmonic state observer (EHSO) is designed for estimation and

As the power required by modern data center processors increases, the power architecture must be adapted; for example, 48 V distribution voltage allows to reduce copper losses by a factor 16 with respect to the use of traditional 12 V power architecture. In order to generate the required processor core voltage, a two-stage approach is usually preferred, where the intermediate bus voltage is generated

Textile-based electronics systems are gaining considerable popularity nowadays and the area of wearable electronics technology is going to explode in the near future. Currently, the research on the flexible and wearable energy storage devices, to realize as power sources in wearable electronics, is on the boom. Herein, a flexible yarn-based supercapacitor (YSC) is fabricated utilizing TiO2 nanofibers

Conventional battery balancing techniques target fast voltage or state-of-charge convergence while improving circuit-level metrics such as power density, efficiency, and component count. System-level metrics, including prolonged pack cycle life, reduced degradation rate, and increased energy capacity, are often overlooked. In this work, the lifetime discharge energy of imbalanced battery packs is quantified

This article discusses the feasibility of signal-injec- tion sensorless control (SISC) in low saliency surface-mounted permanent-magnet synchronous motors (SMPMSMs). At first, dynamic inductances of a target SMPMSM according to rotor position and dq-axes currents are measured from an experiment. The current response induced by the injected voltage is theoretically calculated based on the inductances

DC bias in a transformer is a threat to the safe and efficient operation of dual active bridge (DAB) converters. Detecting a dc component in milliamperes mixed with a large ac current is difficult. This article proposes a current sensor based on ac magnetic flux (MF) cancellation. The proposed sensor utilizes a current transformer (CT) to extract the ac component in the measured current. Then, a power

This article proposes an improved position sensorless drive method for interior permanent magnet synchronous machines (IPMSM) in medium- and high-speed regions, which relies on the fully discretized extended back-electromotive force (EEMF) model and online inductance identification. First, the fully discretized EEMF model is developed for constructing position observers, which overcomes the accuracy

This article introduces the measurement and analysis of the transient electric field (E-field) derived from the switching operation of the modular multilevel converter (MMC) and the high voltage direct current (HVdc) circuit breaker (CB) in a 200 kV converter station constructed in the Zhoushan Islands, China. It is revealed that the switching transient E-field in the converter station is a quasi-static

This article proposes a space vector pulsewidth modulation using space voltage vector mapping and the midpoint-voltage self-balancing strategy to overcome the shortcomings of the existing active neutral-point-clamped five-level inverter modulation. Through multispace mapping, the five-level topology is converted into multiple two-level topologies for calculation. It greatly simplifies the computational

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.

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.

This article presents a quasi-single-stage current-fed resonant ac–dc converter having improved heat distribution. Secondary-side switches are turned off with the voltage closed to zero at high instantaneous power and with the voltage closed to the half of the output voltage at low instantaneous power. Switching losses at the primary-side bottom switches are reduced; this change improves the heat distribution

The lack of uniform production of panels in photovoltaic (PV) systems and snowball effects in fuel cell (FC) systems led us to use a separate dc–dc converter. In addition, in the PV and FC systems, the output voltage is low. Hence, dc–dc boost converters are commonly used in a series connection. Each small unit of a PV or FC operates independently. Therefore, another problem arises in the system that

AC-to-DC conversion is integral to the two-stage charging interface of electric vehicle (EV) batteries. For such chargers, the use of multilevel rectifiers (MLRs) reduces voltage ratings of power switches, while achieving a high-quality input voltage waveform. Balancing of capacitors in MLRs, however, is an important challenge. In this work, a power factor correction (PFC) five-level rectifier with

A silicon/silicon carbide (Si/SiC) hybrid switch (HyS), comprised of a high-current Si insulated gate bipolar transistor and a low-current SiC metal oxide semiconductor field effect transistors, gains attention because it offers lower on-state loss under both light and heavy loads. However, the dynamic overcurrent stress experienced by the HyS under the heavy load has to be coped with to avoid reliability

This article presents an efficient and fast echelon battery equalization method based on wide voltage range bidirectional converter combined with DBSCAN (density-based spatial clustering of applications with noise) clustering control strategy. Thanks to the wide voltage range and bidirectional buck-boost characteristics of the four-switch bidirectional converter, the battery energy can be reasonably

This letter proposes a settling-angle-based stability criterion, as the extension of determinant-based general Nyquist criterion, to facilitate the stability analysis of nonminimum phase power systems with multiple current-controlled converters. Using only the phase information of converter impedance in the $dq$-frame, the proposed stability criterion can accurately demonstrate the system stability

This article presents a tri-port current-source soft-switching medium-voltage string inverter (TMVSI) to reduce the Levelized cost of energy (LCOE) of large-scale solar-plus-storage (SPS) farms. Throughout this work, the topology, operating principle, circuit simulation, control, and hardware design of the TMVSI are introduced. In addition, three key challenges compromising the performance of the TMVSI

Class-E power amplifiers are widely used in megahertz frequency power conversion systems due to their high efficiency, which can further be enhanced by virtue of wide-bandgap devices such as GaN high-electron-mobility transistors. Here, a GaN-based cross-quadrant mode Class-E amplifier is proposed, which addresses one of the major challenges for such amplifiers, i.e., to achieve both high power and

Under the condition of the unbalanced grid, the second-order harmonic voltage ripple exists on the dc bus of the three-phase PWM rectifier. In this article, the internal relationship between the dc bus voltage ripple and the dc bus impedance is revealed. In addition, this article proposes a voltage ripple suppression method free from the power model, which can improve the system robustness against

In this letter, a novel magnetic coupler with high rotational misalignment tolerance is proposed for unmanned aerial vehicles (UAVs) wireless charging. The transmitting coil consists of an inner coil and an outer circular coil connected in series, which generates a horizontal magnetic field from the center to all periphery directions within the charging range. Then, to receive the flux effectively

Random pulsewidth modulation (RPWM) with variable carrier frequency generally disperses the dominant PWM harmonics more effectively than the RPWM with constant carrier frequency. But variable carrier frequency results in variable sampling frequency, which changes controller parameters and makes RPWM difficult to use in closed-loop applications. To significantly disperse dominant harmonic clusters located

Lithium-ion batteries offer excellent advantages of high efficiency, small size, and low cost, but their instability and inconformity remain challenging. Sudden failure of batteries may cause serious accidents, endangering the safety of people’s lives and properties. Advanced remaining useful life prediction methods for batteries can effectively avoid those accidents. In this article, we proposed a

The magnetic elements are the important parts of the dc–dc converters, which is the constriction to improve the power density of the systems. In this letter, a magnetic integration structure is proposed to integrate the magnetizing and leakage inductance for split transformer with standard UI cores, which are mass-produced. Compared with the EI/EE-core structure to achieve magnetic integration, the

Electroactive polymers show promising characteristics, such as lightness, compactness, flexibility, and large displacements, making them a candidate for application in cardiac assist devices. This revives the need for quasi-square wave voltage supply switching between 0 and several kilovolts, that must be efficient, to limit the heat dissipation, and compact in order to be implanted. The high- access

The modular multilevel converter (MMC), used in high-voltage dc applications, consists of hundreds of submodules in each arm. The operation and control of the MMC require sensing of the capacitor voltage of each submodule. The transmission of the sensed data from hundreds of submodules over individual channels leads to wiring complexity. This work suggests that time-multiplexing can be used to transmit

Like conventional two-switch leg converters, the three-switch leg converters also have short-circuit risks and a dangerous shoot-through current is generated if switches of the same leg are turned on simultaneously. In this article, a new dual-buck structure is proposed for three-switch leg converters. The proposed structure is reliable because of no shoot-through concerns and high quality of output

The aim of this study is to introduce the maximum torque per total ampere (MTPTA) control strategy for brushless doubly fed induction machine drives taking iron loss into account. In this regard, the condition for realizing the MTPTA is investigated in the presence of iron loss by a theoretical approach. It is shown the proposed strategy is realized when the MTPTA criterion tracks zero as reference

This article proposes a dual-frequency wireless power transfer (WPT) with dual CLCL hybrid compensation topology and multilayer self-decoupled compact coils (MLSDCCs). It extends the transmission distance corresponding to stable high transmission power and efficiency. Based on the parameter constraints of compensation capacitances and inductances, CLCL hybrid compensation topology realizes simultaneous

This article presents a sensorless control strategy by injecting high-frequency (HF) voltage into the d-axis for the interior permanent magnet synchronous motor (IPMSM) in the full speed range. The defined quadratic virtual back electromotive force model can be adopted in the full speed range, and thus, there is no need to design a transition algorithm from the zero–low speed to the medium–high speed

The ripple effect phenomenon wherein the capacitor ripple voltage generates the fundamental-frequency output ac voltage of a cascaded H-bridge-based static synchronous compensator (CHB-StatCom) is revealed and investigated in this work. First, an observation method of the ripple effect for the CHB-StatCom is presented. Then, the reason why CHB-StatCom has a ripple effect is explained. Subsequently

This article proposes a new open-circuit (OC) fault diagnosis method for power switches in three-level neutral-point-clamped (NPC) rectifiers. This method is based on fault assumption by introducing a new voltage deviation for diagnosis, which is the difference between the switching-state-based voltage and the fault-assumed-based voltage, where the fault-assumed-based voltage is the estimated pole

The recently proposed independently controlled multiple output flyback converter (ICMOFC) scheme improves cross-regulation by utilizing gallium nitride (GaN) switches with negative gate turn-off voltage. The highly inefficient reverse conduction (RC) of negative gate biased GaN devices leads to significant RC loss in the existing ICMOFC scheme. To mitigate this problem, this letter proposes a new pulsewidth

Position sensorless control of interior permanent magnet synchronous motors (IPMSMs) is of great importance for the sake of the cost reduction and robustness improvement. An improved position sensorless method based on adjustable high-frequency (HF) square-wave voltage injection has been proposed for the IPMSM drive under zero- and low-speed regions. The general detection method of position from positive-

The dynamics of nonresonant dual-active-bridge converter (DABC) are simultaneously affected by the transient modulation strategy and controller design. In general, inappropriate transient modulation strategies can lead to nonzero transient dc offsets in the inductor current and transformer’s magnetizing current, thus introducing excessive trajectory tracking error and time delays between the pulsewidth

Compared with the traditional control method, the direct torque control and direct force control method significantly reduces the torque ripple and the root-mean-square current of the phase winding in the single-winding bearingless switched reluctance motor. However, due to the unreasonable selection of voltage vectors and full cycle control, this method has some problems, such as too many control

The single gate driven series connected power device stack possesses the advantages of high compactness and low cost. However, research of its short circuit (SC) characteristic remains uncovered. This article fills this gap and points out that, with the single gate driver it has the potential of over-current limitation. Furthermore, based on it, an improved single gate driven silicon carbide (SiC)

Five-level flying capacitor (5L-FC) rectifier is advantageous in unidirectional power applications due to its less power devices, higher power density, better reliability, etc. To further improve the efficiency, discontinuous PWM (DPWM) methods are preferred. This article investigates a carrier-based implementation of DPWM for the 5L-FC rectifier to reduce the switching losses. Since there is always

Utilizing coil inductor of electromagnetic vibration energy harvester (EVEH) to form single stage ac–dc boost converter can make the self-powered milli-power system more compact. However, large output current harmonics of EVEH significantly degraded the output power in such system. This article proposes a new approach of adopting hysteresis current control to realize maximum power point tracking (MPPT)

This article compares different strategies used to enhance the stability properties of grid-following voltage-source converters (VSCs). Because of digital delays, VSC admittance exhibits a nonpassive zone, which introduces negative damping and may destabilize the grid-connected operation. It is shown that typically used active damping (AD) strategies only bring positive impact up to a certain frequency

This article proposes a high-gain transformerless three-port converter (TPC) for standalone photovoltaic (PV) systems. The TPC is designed and developed based on a dual-inductor high-gain two-port converter by utilizing one of the buffer capacitors to derive the third part for PV input. A hybrid pulse-frequency modulation scheme unified with a pulsewidth modulation control strategy is adopted, which

Multiphase dc-excited Vernier reluctance machine (DC-VRM) exhibits the merits of robust structure, small torque ripple, and good fault-tolerant ability. Developing advanced sensorless drive methods can further promote its application in the safety-critical system. In this article, pulse injection sensorless drive methods are optimized in a six-phase DC-VRM parallel H-bridge drive system to strengthen

In this article, the influence of thermal coupling in power modules on lifetime under power cycling test (PCT) is investigated. In a full-bridge power module for electric vehicle application, the thermal coupling is strong due to high power density and causes lateral temperature difference. In PCT, at the same maximum junction temperature Tvjmax and temperature swing ΔTvj, the influence of thermal

As one of the promising power interfaces between the energy storage components and the dc link, dual active bridge (DAB) converters have gained extensive researches. Its reliability and healthy operation under one or even multiple unexpected open-circuit faulty conditions have become one of the main design challenges. Conventional fault detection (FD) and fault isolation (FI) methods exhibit obvious

In this article, a self-synchronized, high-frequency class E resonant rectifier is proposed to compensate for the synchronization signal mismatch due to the propagation delay. The synchronous rectification helps the power conversion system increase its efficiency by using active devices such as mosfets instead of diodes. Even with the mosfets, it is still challenging to generate an accurate synchronous

This letter proposes a switched capacitor (SC)-based continuously adjustable modular bidirectional dc–dc converter. The structure of the proposed converter consists of three types of modules, series–parallel SC converter module, regulating module, and resonant SC converters module. A basic configuration of three modules working in buck operating mode is analyzed in detail. The boost mode operation

This letter demonstrates that the second-order generalized integrator-based frequency-locked loop (SOGI-FLL) with a soft startup/rate limiter essentially incorporates an adaptive feedforward relying on a priori information of transient input. When a fair parameter is tuned, the soft startup and the limiter give a similar performance. The shortcoming is that they have a deceleration blind zone, depending

This letter proposes a multiagent soft actor-critic (MASAC) enabled multiagent deep reinforcement learning (MADRL) algorithm for output current sharing of the input-series output-parallel dual active bridge converter. The modular converter is partitioned into different submodules, which are treated as DRL agents of Markov games. Furthermore, all agents are executed decentralized to provide online control