A MOSFET is often applied as the switch in medium and small power single-phase full-bridge inverters. In order to achieve efficient operation at a high switching frequency, a new efficient inverter is presented in this paper. In addition, two sets of identical auxiliary units are arranged on the two bridge arms. When the main switches need to be turned on in each switching period, the voltage across

The overmodulation operation of a three-phase inverter can enhance the output torque capacity of the AC motors. In this case, the enhancement varies depending on the overmodulation schemes applied for the overmodulation operation. Steady-state overmodulation schemes are usually employed to give the unit voltage gain up to the six-step mode of an inverter. However, these schemes lead to a slow transient

The breakdown strength and electron mobility of gallium nitride (GaN) are almost ten and three times higher than those of the silicon devices. Wide band-gap devices have a higher thermal conductivity, higher switching frequency capability, lower on-state resistance and lower power dissipation. Detailed analytical models in the electrical network and channel current variations of these devices during

Generally, position controllers for servo motor drives utilize cascaded structures with speed and current controllers in inner loops. This structure provides easy gain setups and independent limits for control variables such as maximum torque or speed. However, it suffers from a large computation time and poor dynamic characteristics for the position control since the bandwidth must be low enough to

The series capacitor converter is one kind of high-gain bidirectional DC–DC converter based on interleaved and switched capacitor techniques. For the n-phase series capacitor converter, n times voltage gain when compared with the traditional boost converter under a specific duty cycle, as well as automatic current sharing among phases can be achieved. The specific duty cycle is (n − 1)/n to 1 in the

An optimization approach for automotive power semiconductor switch module with shunt resistor using an inlay printed circuit board (PCB) is proposed in this study to analyze electrical and thermal characteristics under a given maximum temperature rise constraint. The final module with a shunt resistor and current measurement block is designed and manufactured by adopting the optimization results. The

An open-end winding induction motor drive system fed by two boost inverters with fault-tolerant capability is presented to improve the reliability and safety of the drive system. The boost inverters consist of an impedance-source network and a two-level inverter. It can realize the boost/buck function. An analysis of its fault-tolerance is presented in detail. Short circuits and open circuits are commonly

This paper discusses an isolated switching mode power supply (SMPS) with an AC 30 kVrms insulation capability for application to the solid-state transformers (SSTs) in railway vehicles. The insulation capability of the SMPS should be higher than AC 25 kVrms for application at the SSTs in railway vehicles. The proposed highly isolated SMPS is superior to commercial isolated power supplies with low insulation

Estimation of the state of charge (SOC) of a lithium-ion battery is one of the key technologies in battery management systems. The accuracy of SOC estimation mainly depends on the accuracy of the battery model. The traditional Thevenin model has limited application due to its fixed parameters. In addition, its accuracy is not high. This paper proposes a variable parameter equivalent hysteresis model

This paper proposes a simple current control method without a grid voltage sensor for a rectifier of traction solid-state transformer. The proposed control scheme estimates the phase angle of grid voltage from the fundamental frequency current of the grid. The extracted phase signal is normalized to generate a sinusoidal current reference by adopting a scaling factor to achieve a unity gain. Since

Quasiresonant converters (QRCs) are increasingly being used in autonomous power supply systems. These converters are efficient, have small dimensions, and operate stably when the load changes. This study is devoted to the development of a zero-current switching QRC with improved characteristics. The main advantages of this QRC are a wide range of regulation and a low level of output voltage ripple

Due to the advantages of multiple power supply points and multiple power receiving points, the multi-terminal direct current (MTDC) technology has gradually become the main trend in the future development of DC power grids. The coordinated control of a MTDC system is one of the key technologies to realize the stable operation of power systems. Droop control is an effective coordinated control method

This paper presents a method for transitioning between sensorless rotor position estimation methods for an interior permanent magnet synchronous motor (IPMSM). Through the proposed method, rotor position estimation over the entire speed range of the IPMSM is possible. Considering that each sensorless method governs a different speed range for estimating rotor position and speed with good accuracy,

This study proposes a modified modulation scheme based on the phase-shifted pulse-width modulation (PS-PWM) method to improve the output performance and reduce the switching loss in cascaded H-bridge multilevel inverters. The PS-PWM method is one of the most popular modulation schemes. However, it generates significant switching loss, which can lead to the failure of power semiconductor switches. Various

For high-power quasi-continuous laser drivers, the switched pulse power supply (PPS) is a promising technique due to its higher efficiency when compared with linear drivers. However, there are some digital control challenges with high precision, fast response and zero overshoot during the flat-top current stage. To promote the use of a switched PPS, this paper proposes a digital control strategy based

The delay effect caused by the switching device is not considered in traditional methods of induction motor flux observation. However, ignoring the delay effect causes the mathematical model of the induction motor flux observation to be inaccurate. In actual work, this disadvantage will affect the flux observation of the induction motor. It will also influence the anti-load performance of the motor

This paper presents a fault online simulation (FOS)-based diagnosis scheme for single and simultaneous open-circuit faults of voltage-source inverters in closed-loop-controlled permanent magnet synchronous motor (PMSM) drive systems. First, the hybrid model (HM) of the motor drive system is established, and the current observer is designed according to the normal HM to detect the fault. This approach

A device modeling and topology design method suitable for high-power-density and high-temperature applicationare important to develop with the development of devices. A novel multi-physics analysis model based on GaN high electron mobility transistor (HEMT) is proposed in this paper. The coupled electromagnetic and electrothermal model for GaN HEMT is beneficial to simulate a device’s external characteristic

A microgrid (MG) is an effective way to integrate various distributed generators (DGs) into a power distribution system. The synchronization of DG voltage with MG voltage is indispensable to prevent inrush currents before connection to a MG system and for working in parallel with other DGs in the MG. In the past, synchronization in terms of both phase and magnitude was realized using additional voltage

A Lorentz force-type magnetic bearing (LFMB) with good linearity is suitable for the high-precision deflection control of a magnetically suspended gimballing flywheel (MSGFW). In this paper, a novel LFMB with improved double magnetic circuits is presented. Inclined magnetization Halbach array permanent magnets (PMs) and trapezoidal PMs are utilized for improving the magnetic flux density. A mathematical

This paper proposes a model-free predictive current control (MFPCC) for interior permanent magnet synchronous motors (IPMSMs) with a multiple current difference updating (MCDU) technique. Firstly, to improve robustness against machine parameter variations and reduce the computational burden, current difference-based prediction that only requires accumulation operation is implemented, which avoids the

A digital current sharing control method leveraging a CAN bus is developed to inhibit the fluctuating current distributions of parallel converters in high-output oxidation power systems. When compared to conventional current sharing strategies, the proposed design significantly reduces circuit complexity without resorting to an analog current sharing bus, and is extremely robust in maintaining system

Cascaded multilevel inverter cells produce double-grid frequency ripples that require a large electrolytic capacitor bank for every cell, resulting in reduced system reliability and lifespan. This paper proposes a new generalized power-decoupling methodology that is applicable to any three-phase cascaded multilevel inverter topology. The proposed flux cancellation method is based on forcing a three-phase

A typical battery energy storage system consists of a combination of battery packs and a grid-tied power conversion system. The control algorithm of the power conversion system plays an important role when interfacing the DC energy stored in battery packs with the conventional AC grid to generate an obedient bidirectional power flow. Finite control set model predictive control is believed to be one

This paper proposes a new approach that allows the diagnosis and the ability of discernment between the frequency signatures of eccentricity faults and those of demagnetization in a permanent magnet synchronous motor (PMSM). This approach is based on the application of a very selective band-pass filter in the stator current. A judicious calculation of the parameters of this filter makes it possible

In this paper, a simplified active islanding detection method based on a power control disturbance signal for a three-phase grid-connected inverter application is presented. The disturbance and observation method is used to simplify the significant indicator, which determines the islanding condition. The control algorithm, which is used to command the observation and disturbance method, is derived

For dual-active-bridge (DAB) DC-DC converters, a variable frequency triple-phase-shift (VF-TPS) modulation strategy based on a particle swarm optimization (PSO) algorithm was proposed to solve the problem of the low efficiency of TPS modulation in larger power conditions. To facilitate the implementation of the PSO algorithm, the mathematical expressions between the transmission power or the RMS square

The conventional current and voltage control methods of AC/DC power factor correction (PFC) rectifiers have been applied using proportional-integral (PI) or proportional-resonant controls. However, these approaches do not guarantee global stability at various operating points and are sensitive to disturbances, such as parameter or load variations. In this paper, a new control method is proposed based

Due to an unfortunate oversight the acknowledgement section has been omitted.

A current-balancing strategy for a multileg interleaved DC/DC converter with a reduced number of current sensors for electric-vehicle chargers is proposed in this paper. There are imbalances between the leg currents of multileg DC/DC converters, which are caused by the difference between the leg impedances and the driver delay. Each of the leg current sensors must achieve current balancing. However

This paper proposes the independent switching technique to remove abnormal output voltage in hybrid active neutral-point clamped (ANPC) inverters. The hybrid ANPC inverter is composed by mixing silicon (Si) devices and silicon carbide (SiC) devices, unlike the conventional ANPC inverter which is generally composed of Si devices only. SiC devices provide low switching losses under a high switching frequency

In this paper, a new SVPWM switching technique, named ZSVM_1TI, has been proposed for a three-level (3L) T-type Z-source inverter (ZSI). ZSVM_1TI is based on three main modifications of the existing PWM techniques for 3L inverters. First, the existing SVPWM of a 3L ZSI has been modified to double the frequency of the null interval. After that, an improved version of the maximum boost control (MBC)

Existing PWM methods suffer from a tradeoff between zero-sequence circulating current (ZSCC) and line-current ripple, which are two major concerns of two parallel interleaved two-level (2L) voltage-source converters (VSCs). Thus, this paper introduces a novel space vector-based PWM strategy to reduce both line-current ripple and ZSCC. Given the redundancy of the vector combination of two parallel interleaved

This paper studies the characteristics of SiC inverter powertrains on common-mode (CM) EMI emission. First, a CM noise source model of an EV powertrain is built. Then, the factors of switching frequency, switching speed, and switching ringing on the CM noise source are analyzed. Finally, experiments on a conducted EMI test-bed are carried out to verify the influence of SiC inverters on conducted CM

To study the temperature distribution and change the law of the permanent magnet synchronous motors used in vehicles during extreme driving, the concept of extreme variable working condition (a running process from a low-power condition where a motor can run for a long time, to peak power and then to a low-power condition) was proposed. To calculate the temperature field, an overall simplified model

This paper analyzes and compares the typical rotating high-frequency voltage injection (RTHF) method and the typical pulsating high-frequency voltage injection (PSHF) method in terms of torque ripple and vibration. Analysis and experiment results indicate that the PSHF performs better when it comes to torque pulsation and vibration. In addition, it is more suitable for rim motors which have strict

This paper presents an enhanced compensation strategy for distributed generation (DG) systems to simultaneously achieve accurate power sharing and harmonics compensation at the point of common coupling (PCC). In the proposed control strategy, the output impedance is modified at the fundamental and harmonic frequencies to compensate for the line impedance mismatches among DG units, which results in

A high step-up isolated forward–flyback DC–DC converter with pulse frequency modulation (PFM) is presented in this paper. The proposed converter has features of both a forward and a flyback converter and can deliver energy during the turn-on and turn-off intervals in a switching period. In addition, by utilizing resonance it can achieve zero-voltage switching (ZVS) for the primary switches and zero-current

The LCL filter is widely used in grid connected converters for good harmonic mitigation performance. With pulse width modulation strategy, converter terminal voltage contains various sideband harmonic components together with expected components corresponding to the modulation wave, especially under a low switching frequency. Considerable resonant current can be generated if the undesired sideband

A modified topology to obtain a high efficiency bidirectional type DC–DC converter without magnetic coupling is proposed in this paper. The modified circuit contains four switches with their body diodes, two inductors and a capacitor, and the topology arrangement uses two boost converters to develop the gain. The input current of the modified topology is divided between two different values of inductors

State of charge (SoC) balancing and accurate power sharing have been achieved among distributed batteries in a DC microgrid without a communication network by injecting an AC signal. The frequency of the generated signal is proportional to the SoC of a predefined master battery and it is used for the other batteries as a common variable to estimate the SoC and output power of the master battery. Based

Wide band gap semiconductor device silicon carbide (SiC) metal oxide semiconductor field effect transistors (MOSFETs) have many advantages and are considered to be the most promising alternative to silicon (Si) insulated gate bipolar transistors (IGBTs) in low-/medium-voltage fields. However, a faster switching speed results in more serious electromagnetic disturbance problems in the application of

A new three-phase buck/boost/buckboost power factor correction rectifier is presented in this paper. For the converter, only two high-frequency switching actions exist in each sample period, and only one inductor is used. As a result, system efficiency can be improved. The commutation procedures are analyzed for the three modes, the controller design of the rectifier is discussed, and the output duty

The right-half plane (RHP) zero in the control to output voltage transfer function of a boost converter operating in the continuous conduction mode limits the loop bandwidth. By injecting a scaled version of the inductor current into the loop, it is possible to shift the zero from the right-half plane to the left-half plane, which leads to increased stability of the control loop. This solution generates

With the rapid development of semiconductor technology, the applications of silicon carbide (SiC) MOSFETs have been booming in recent years, where short-circuit fault protection plays an important role. In this paper, voltage and current waveforms under different short-circuit faults are analyzed. Then, two types of turn-off modes, namely a soft turn-off mode and a two-stage turn-off mode are introduced

Due to an unfortunate oversight, the funding number of the Fundamental Research Funds for the Central Universities has been given erroneously. It should be read: 2013/2019B04114

A new structure for doubly fed induction generator (DFIG) wind farms with coordinated power control under grid fault conditions are proposed in this paper. The proposed structure uses one grid side converter (GSC) and one energy storage system (ESS) for the entire wind farm unlike conventional structures, which have one GSC for each of the DFIGs. A converter loss decrease and a reliability enhancement

This study implemented a 30 kW, 750 Vdc, silicon-carbide (SiC)-based uninterruptible power supply(UPS) applied it on a three-phase four-leg inverter. For component selection, LC filter and DC-link capacitor were designed based on the PSIM simulation. SiC MOSFET was used to achieve higher efficiency and better reliability than the conventional Si IGBT-based UPS applications. Furthermore, desaturation

In this paper, an online junction temperature monitoring method based on the on-state voltage under high collector current density measurements for IGBT power modules is proposed. Unlike the conventional junction temperature monitoring method, the presented method can extract the junction temperature during operation without altering the modulation strategy or topology of the converter. The proposed

The soft-switching buck inverter, which is mainly applied to solve the contradictions between the switching frequency and the shoot-through problem along with the dead-time effect, is proposed in this paper. A detailed analysis of the relationship between the range of the duty ratio to realize soft-switching as well as the additional voltage stress and the current stress is conducted. In addition,

With the rapid development of DC transmission technology, DC circuit breakers, the key equipment for DC fault handling, have become a research hotspot of scholars. This paper proposes a novel hybrid DC circuit breaker topology to improve the shortcomings of traditional hybrid DC circuit breakers. Traditional hybrid DC circuit breakers use too many IGBTs, which results in a large volume and a high cost

Under an unbalanced network, model predictive control (MPPC) with a new definition of the instantaneous reactive power has attracted a great deal of attention due to its simple control structure and outstanding steady-state performance. However, the reactive power cannot precisely trace the nonzero reference. In this paper, a model predictive DC-component power control (MPDCPC) is proposed to tackle

Due to an unfortunate oversight some equations (4, 5, 6 and 7) have been given errorneously.

This study proposes a design of an inner control loop for the load torque control of an electric load simulator (ELS), which is specifically designed to simulate load torque (i.e., load) for mechanical equipment. By mainly drawing on linear active disturbance rejection control, a mechatronic model-based inner loop controller of ELS is designed using measured torque to reduce the complexity of the estimator

Flux estimator (FE) is critical for achieving high-performance sensorless drive of induction motors. A voltage model (VM) is an excellent candidate for a FE since it does not require speed information and has a simple structure. A VM using a closed-loop style has excellent sensorless drive capability over a wide speed range. However, it is limited by the uncertainties such as offset and parameter mismatch

The carrier phase-shift PWM strategy is widely used in modular multilevel converters to satisfy the driver demands of the numerous switches in submodules. However, the traditional carrier phase-shift PWM strategy can cause an imbalance phenomenon in the submodule capacitor voltages, which deteriorates the system working performance. This study develops a mathematical model of an MMC system, which is

Although the silicon carbide (SiC) metal–oxide–semiconductor field-effect transistor (MOSFET) is superior to the conventional silicon (Si) insulated gate bipolar transistor in terms of switching performance, the switching losses of SiC devices increase rapidly by hard switching when the switching frequency (fsw) increase to hundreds of kilohertz (kHz). This paper proposes an auxiliary zero-voltage-transition

In a three-phase multilevel cascaded inverter (MLCI), when a failed module is bypassed, the number of modules in each phase becomes unbalanced. Under this condition, a method to obtain a balanced three-phase output is to move the neutral point of the MLCI. The neutral-point shift (NS) method has attracted a great deal of attention since the output of the inverter has a relatively low harmonic distortion

Silicon carbide (SiC) metal–oxide–semiconductor field-effect transistors (MOSFETs) are expected to be an attractive replacement for Si MOSFETs in high power applications due to their high blocking voltage, high switching speed, and low switching losses. However, a high switching speed can lead to voltage and current overshoot as well as oscillation during the switching process, which results in additional

With the large number of applications for multi electric aircraft (MEA), the power capacity of the aviation static inverter (ASI) has been continuously improved. Therefore, more and more modular parallel-based topologies are being used in the ASI to achieve power expansion. Combined with carrier phase-shift modulation, the harmonic components of a system can be further reduced. However, due to the