This paper presents a PI gain design and decoupling voltage compensation method for vector-controlled switched reluctance motors, incorporating inductance harmonics up to the 10th order. Unlike conventional approaches that consider only the DC and 2nd-order components, the proposed method effectively suppresses 6th-order dq0-axis current ripple during high-speed operation. Simulation results demonstrate that incorporating at least the 4th-order inductance harmonics significantly improves current tracking and reduces the current ripple at a rotational speed of 30,000 min⁻¹, achieving an 81.7 to 90.8% reduction in 6th-order dq0-axis current ripple compared to conventional methods.

This paper discusses the inrush current of an inverter-equipped refrigerator connected to a domestic power outlet for various source-voltage phase-angles. A theoretical equation for the inrush current is derived to calculate the peak values of the inrush currents for various source-voltage phase-angles. The peak value of the inrush current is maximized at a source-voltage phase-angle of 60◦. The derived equation is verified by a digital computer simulation, performed using PSIM software. Simulation results show that the peak values of inrush currents agree well with those calculated using the derived equation.

In this paper, a novel permanent magnet biased bearingless switched reluctance motor (BSRM) is proposed based on traditional 12/14 BSRM. The proposed structure adopts stepped rotor structure and inserts permanent magnets in the middle of each suspension pole to generate biased magnetic field. Compared with traditional 12/14 BSRM, it has advantages, such as achieving self-starting at any rotor position, greater bearing capacity, better decoupling characteristics between torque and suspension force, and less suspension loss. The characteristics of the proposed and traditional structures are analyzed and compared by finite element method to verify the effectiveness of the proposed structure.

This letter proposes a T-type multi-level linear amplifier (TMLA) as a new topology of Multi-level linear amplifier (MLLA) circuit based on the T-type NPC multi-level inverter. The proposed TMLA can improve output voltage drop and efficiency because the output current passes through only one MOSFET when outputting large voltages compared to other topologies of MLLAs. The principal operation of the proposed TMLA was verified by LTspice simulation.

Advances in semiconductor technology have dramatically improved the computing performance of controllers in embedded control system, making it possible to realize fast and precise control systems. In this study, 10 MHz multi-sampling deadbeat (MSDB) control was applied to a permanent magnet synchronous linear motor (PMLSM) drive system with a 20 kHz carrier frequency inverter using an FPGA controller. Simultaneously, a high-speed encoder detection system with T-methods based on 100 MHz DIO was implemented. The control characteristics of the proposed method and the conventional motion control method were evaluated and compared through simulations and experiments. As a result, it was confirmed that the proposed method achieves fast control response and robust characteristics compared to a conventional PI control and single-rate deadbeat (SRDB) control. Threfore, in this study we demonstrate the effectiveness of the proposed next-generation motion control method, which can achieve both high control response and robustness.

This paper proposes a compensation method for addressing transmission power errors in dual active bridge (DAB) converters operating under fluctuating DC-bus voltages. Transmission power errors arise from dead time, whose effect varies nonlinearly with the relationship between the transformer turn ratio and the voltage ratio. The proposed method classifies nonlinear errors into five operating modes within a three-level framework. By combining phase-shift control with zero-voltage period adjustment on both the primary and secondary sides, the method effectively compensates power errors while reducing switching losses. Unlike conventional two-level operation, where two legs undergo hard switching under dead-time influence, the proposed method limits hard switching to at most one leg. Experimental results show the effectiveness of the proposed method, demonstrating a reduction in the maximum power error from 0.43 p.u. to 0.024 p.u. when the output voltage is increased by 25%. Furthermore, the method achieves a maximum efficiency of 93.9%, reducing losses by up to 25.2% compared to conventional two-level operation.

With the widespread integration of photovoltaic (PV) power generation into power grids, the reliability of PV converters is becoming crucial, and there is an urgent need for comprehensive testing before PV converters are put into field operation. Due to complex mission profiles, significant challenges have been experienced to reliability testing. A mission profile emulation (MPE) system, involving a three-level neutral-point-clamped (NPC) converter and a two-level converter, is proposed as a promising method for new approaches of converter testing, offering programmable mission profiles, improved testing efficiency and reduced testing costs. Typically, to reduce power loss, DC links of two converters are connected to achieve power circulation, which inevitably creates zero-sequence current, as can be classified as high-frequency zero-sequence ripples and low-order zero-sequence harmonics, and will further result in current distortions. However, in terms of MPE system with different converter topologies and mismatched carriers, mechanism of zero-sequence current excitation remains unclear, and potential sampling distortions and control errors have seldomly been studied. In this paper, the mathematical model of zero-sequence current in MPE system with different converter topologies and mismatched carriers is established. Impacts of zero-sequence current, including waveform distortions, sampling distortions and control errors, are also discussed in details.

A two-winding method is widely used for inductor core loss measurement in power converter circuits. However, this can lead to measurement errors when applied to low-permeability materials or when the secondary winding cannot be implemented. To overcome these challenges, this study evaluates the feasibility of the single-winding method for core loss measurement by subtracting copper loss to estimate core loss. Air-core inductors were introduced in the experiment to verify the accuracy of the core loss measurement results. In addition, several copper loss calculation methods were compared, and recommendations for different testing conditions were provided. Experimental results confirmed that the single-winding method is a practical alternative for core loss measurement when the use of secondary windings is restricted.

With the advantages of high precision, high reliability, and strong environmental adaptability, resolvers play a central role in position detection across various fields, including aerospace, automotive, and servo systems. However, prolonged operation in harsh environments can lead to faults such as eccentricity and short/open winding, and interference from non-ideal factors. These issues lead to a decrease in position detection accuracy and potentially cause system failure. Thus, fault diagnosis technology has become the focus of considerable research interest. This paper summarizes the research progress related to fault diagnosis of the resolver. First, it explains the working principle of the resolvers and rotor position extraction methods, clarifying their signal output characteristics. Next, it classifies and analyzes typical faults such as eccentricity, winding faults, and those caused by non-ideal factors. systematically summarizes diagnostic methods, including those based on signal processing, model resolution, and artificial intelligence, comparing their diagnostic accuracy, real-time performance, and applicability. Finally, it identifies common challenges in current research, such as unclear fault characteristics, insufficient synergy between diagnosis and fault tolerance, and poor adaptability of diagnostic methods to new structures, and proposes future research directions aligned with technological trends. This review aims to provide a reference for both engineering applications and academic research in resolver fault diagnosis and fault-tolerant control.

Measurement of bi-articular muscle strength related to human limb motor control is required for clinical practice and sports training evaluation. The muscle strength measurement method that utilizes functionally different effective muscle theory employs a two-dimensional musculoskeletal model of six muscles for two joints, wherein limb muscles are classified according to their functions and used to measure the muscle strength for each muscle group. In this study, we evaluate the muscle strength measurement system (MSMS) of each muscle group in a five-muscle model including a bi-articular muscle of the knee-ankle joints in ten young adult males. Instructions are provided to participants, and measurements are conducted while checking the results displayed on the monitor. The knee extension torque of MSMS was comparable to that of the conventional joint torque measurement systems. In addition, we propose two new methods for drawing output force distributions (OFD). Five muscle group torques obtained by the two methods are evaluated by the physiological cross-sectional area of the ankle plantar flexors. Reconsidering the measurement instructions given to participants for the two sides of the OFD related to the bi-articular muscle and the OFD drawing methods is necessary.

Efficient warehouse management is critical to optimizing overall logistics performance. This study provides a brief overview of radio-frequency identification (RFID) technology and its application in warehouse operations. A logistics company in Zhengzhou City, Henan Province, was selected as the case study. In its Phase 1 warehouse, traditional barcode system were used, while the Phase 2 warehouse implemented RFID technology. Both short-term and long-term warehouse management capabilities were evaluated. The results indicated that the RFID-enabled Phase 2 warehouse outperformed the barcode-based system, benefiting from features such as non-contact operation, large-scale automated data capture, and efficient information retrieval. These advantages contributed to improved warehouse management performance with in a one month period.

SiC MOSFETs are preferred over Si-based power devices due to their low switching loss and ability to operate at high switching frequency. However, they have drawbacks such as higher noise emissions due to high 𝑑𝑣/𝑑𝑡 during switching transients. The common-mode conducted emissions are caused by displacement current flowing through the parasitic capacitance between switching nodes and ground. This paper proposes a non-destructive method for identifying parasitic capacitances in a full-bridge power module (FBPM) using a combination of time- and frequency-domain measurements. An equivalent circuit model for noise analysis is presented, and parasitic components are characterized for FBPM operating as a single-phase inverter. For validation, calculated parasitic capacitances are compared with values obtained from finite element method (FEM) simulation of 3D model of FBPM.

A modular multilevel converter (MMC) with octal-switch redundant submodules is proposed to ride through open-circuit faults from insulated gate bipolar transistors. Faults are detected using a residual analysis method, followed by prompt compensation for insufficient voltage. An active fault diagnosis method is subsequently applied to accurately identify the faulty switch location, bypass the affected submodule, and engage redundant modules to maintain converter output, thereby achieving ride-through operation for open-circuit faults. The proposed fault ride-through can quickly detect faults and identify the types without requiring additional sensors or complex mathematical models. This ensures the stable operation of the MMC with the proposed octal-switch redundant submodules. The proposed circuit and control are validated through simulations.

In switch-mode power supplies for audio applications, maintaining a low and flat output impedance and achieving a high current slew rate are critical. This paper presents an advanced switch-mode power supply architecture based on a current source and current choppers. Theoretical analysis and simulation results confirm the effectiveness of the proposed system.

In current control systems using a flying capacitor multi-level converter (FCMLC) or a multi-phase interleaved converter (MPIC), modulation using multiple carriers is expected to expand the control bandwidth. This is achieved by sampling and updating command values at the equivalent carrier frequency, which can increase with the number of levels or phases. However, when such a synchronization is applied to an FCMLC, it has been confirmed that the capacitor voltage fails to stabilize at the specified value under certain control gain settings, even under ideal conditions. This leads to degraded current control performance. In this study, an MPIC, which also allows sampling and command value updates at the equivalent carrier frequency, similar to FCMLCs, is introduced for comparison. The differences in the effects of control bandwidth expansion depending on the converter type and circuit behavior under these conditions are investigated through simulations and experiments.

Field modulation and magnetic gearing effects in electrical machines can be derived from the well-known field harmonic theory. This two-part series of papers reviews the origins, history, and relationship of different types of electrical machine technologies and topologies with field modulation and magnetic gearing effects, as well as recent developments. In this Part I, the origins and early development of field modulated and magnetically geared machines are reviewed, including switched reluctance machines, stator-PM machines, vernier PM machines, multi-port machines, and brushless doubly-fed machines, etc. The general principle of field modulation and magnetic gearing effects and the torque production mechanism of field modulated and magnetically geared machines are introduced based on the field harmonic theory. The common features of field modulated and magnetically geared machines are summarized based on the evolution of machine topologies and general principles of field modulation and magnetic gearing effects. It is shown that electrical machines can be unified by magnetic gears, various field modulated and magnetically geared machines can be obtained by different combinations of magnetic field excitations and modulators, which provides guidelines for developing more novel machine topologies with synergies of different field modulated and magnetically geared machines.

The origins and early development of field modulated and magnetically geared machines was reviewed in Part I. This paper (Part II)reviews the recent development of different types of field modulated and magnetically geared machines, including switchedreluctance machines, doubly salient PM machines, flux reversal PM machines, switched flux PM machines, partitioned stator PMmachines, vernier PM machines, and wound field machines, etc. Novel topologies developed by combining different magnetic fieldexcitations and modulators are introduced, including dual-stator vernier PM machines, dual-PM machines, dual-rotor PM machines,and hybrid excited machines.

High-speed path-tracking control for ground vehicles presents challenges that are exacerbated by inherent time delays in vehicle steering systems. Model Predictive Control (MPC) is widely used for path-tracking control due to its high accuracy and performance at high vehicle speeds. However, its complexity and high computational demand pose practical challenges. To address these issues, we propose a practical control design scheme, as an alternative, which integrates feedback, feedforward, and lead compensator components. The feedback component uses output feedback of vehicle lateral errors from a look-ahead point, while the feedforward component provides curvature-dependent compensation. To enhance control bandwidth while preserving vehicle stability, we employed a lead compensator to construct the output feedback controller, optimized via a heuristic loop-shaping method. Simulation studies on a high-fidelity vehicle model were conducted to evaluate the proposed method and compared with an output feedback controller and an MPC in both lane-change and double-lane-change maneuvers. Compared to the baseline output feedback controller, the proposed approach achieved 52.98% and 48.61% reductions in root mean square error for vehicle lateral tracking in single and double lane-changes, respectively. Our method is comparable in performance and robustness to the MPC-based method for highway velocity range while requiring significantly lower computational effort.

The Tactile Internet is an important future-oriented topic focused on real-time communication between humans and machines. Tactile Internet applications require haptic sensor and actuator solutions that are low latency, low weight, bendable, easy to use, wearable, and integrable. This article introduces several wearable haptic interfaces developed by a research team led by the author using a range of technologies. These haptic interfaces aim to bring the sense of „touch“ to both human-machine and humancomputer applications. In this paper, the developed interfaces are introduced. The technological and construction properties are discussed with regard to their function, quality, power consumption, amplitude, frequency response, size, and weight. One presented example is the recently developed electronic skin, which consists of printed capacitive force sensor arrays fabricated using Kapton as substrates. Other examples include technologies based on graphene, dielectric liquids, dielectric elastomers, piezoelectric, and hybrid metamaterials. Perceptual knowledge and multimodal interaction are used to enhance the capabilities of the hardware and for the haptic signal design.