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Multiple active bridge (MAB) converters have gained relevance in applications such as photovoltaic systems, microgrids, aircraft, solid-state transformers, and electric vehicles. One of the challenges for the MAB is the existing coupling between its different ports since the operating point of each port depends on the parameters of the others; therefore, the dynamic response depends on all ports. This article proposes a feed-forward compensation for the MAB converter, which allows for achieving a good dynamic response under load and power supply changes, reducing the coupling issue; additionally, the proposal is not complex compared to other schemes, this work considers a piecewise model instead of the trigonometric model; and for the uncoupling process no linearization is performed, therefore, the operation is secure for different operating conditions. The proposal is described, analyzed, and experimentally tested in a 200 W triple active bridge prototype.

The traditional deadbeat control-model predictive control (DBC-MPC) algorithm is often adopted to reduce the computational requirements. However, for the selection of the expected voltage vector for a grid-connected power converter with an inductor-capacitor-inductor (LCL) filter, only the current tracking error of the traditional DBC-MPC algorithm has been addressed, while the influence of the filter capacitor voltage tracking error was ignored. Therefore, the calculated output voltage vector of the power converter may deviate from the expected value, degrading the system control performance. In this article, an enhanced DBC-MPC control strategy is proposed. The tracking error of the filter capacitor voltage is also considered, which effectively enhances the performance of the control algorithm. Compared with the traditional DBC-MPC algorithm, the output current THD is reduced by more than 56%. An experimental platform of a three-phase two-level grid-connected power converter with LCL filter is established to evaluate the feasibility and effectiveness of the proposed enhanced DBC-MPC control strategy.

This article reviews the transformerless single-phase common-ground (TLSPCG) rectifiers. According to the number of output terminals and the polarity of the output voltage, the existing TLSPCG rectifier topologies are divided into two categories, that is, three-terminal outputs rectifiers with bipolar dc voltage and two-terminal outputs rectifiers with unipolar dc voltage. The principle and characteristics of different TLSPCG rectifier topologies are described first. The fundamental rectifier circuit units and basic circuits for changing input voltage polarity in two-terminal output rectifiers are extracted, respectively. Then, the topological derivation method of the TLSPCG rectifier is proposed. Following this, the comparisons between various TLSPCG rectifier topologies are constructed detailedly in terms of configuration, research status, performance, and applications. Next, the procedure of topology selection and component sizing are designed and verified with a case study. Finally, future development trends of key technologies used to improve rectifier performance are summarized.

This article deals with the postfault operation of a modular multilevel converter (MMC) with multiple submodules failures. A selective harmonic mitigation (SHM)-based fault-tolerant method is proposed where the modulation references of MMC phase arms are modified under postfault conditions to achieve the maximum possible balanced line-to-line voltages using unbalanced phase voltages. In addition to mitigating the low-order harmonics, a set of constraints is defined in SHM equations so that overmodulation is avoided after modification of modulation references. The suggested method optimizes the MMC capacity to provide the highest attainable line-to-line voltages with a suitable harmonic profile under postfault conditions. Furthermore, the proposed method reduces the peak value of common mode voltage (CMV) and high-frequency components of CMV. This function decreases the CMVs adverse impact on the converter and the load. Comparative simulation and experimental results are provided to validate the feasibility and effectiveness of the proposed method.

Green transportation and renewable energy production have attracted a global attention due to the needs of decreasing the environmental impact and still sustain increased energy needs. In this framework, the aircraft and airports are facing a profound renovations towards green technologies, among which the electrical ones are playing a central role. This paper explores how a Smart Transformer can upgrade the existing airport power system, enabling an efficient interface for renewable energy, electric vehicles and the future hybrid/electric aircraft, substituting the ground power units and enabling a smarter behavior of the electrical grid.

Component sizing and energy management are two critical issues that affect the fuel economy of fuel cell hybrid electric trucks. Solving these two strongly coupled problems separately may lead to compromised performance at the system level. To address this concern, this paper proposes a bi-level optimization framework in which the upper level optimizes the fuel cell and lithium-ion battery sizes while the lower level optimizes the power allocation between them. Based on the sizing variables at the upper level, the lower level utilizes convex programming and rolling optimization to generate an optimal energy management solution and returns the solution to the upper level. Then, the upper level runs a particle swarm optimization process to determine the optimal sizes of the fuel cell and battery to minimize the system total cost including the component costs and operating costs. This framework is health-aware in that it considers the fuel cell and battery degradation by incorporating the corresponding degradation costs in the objective function. A case study using a modified CYC_WVUCITY drive cycle is conducted. Results demonstrate that the proposed framework can optimize the component sizes and the power allocation between them while reducing the component degradation. Moreover, this framework can complete the computation within the sampling interval and therefore can be implemented in real-time applications.

Digital twins are emerging in power electronics as a tool for optimized design, fast prototyping, and smart maintenance, given the increasing demand in terms of high power density, reliability, and low cost. A power electronics digital twin can be regarded as a virtual representation of a power electronics system, embodied by a high-fidelity model running in real time, of which the states and model parameters are updated based on the feedback from the sensors or their data fusions. Digital twin models are developed in multiple domains and run in real time or even faster than real time. The data collected from the physical entities are transferred with controlled latencies and quality, and then processed to iterate the models to represent physical power electronics from application-oriented views. However, due to the nonlinearities and fast switching behaviors of power electronics, one significant challenge is to ensure high fidelity and fast computation simultaneously, which stimulates the real-time simulation (RTS) of power electronics with an ultralow time step. Moreover, the electrical, thermal, and electrothermal aspects shall all be considered to improve the model’s accuracy. To consider the uncertainties, the parameters of the digital twin models are either identified by advanced optimization algorithms or represented by probabilistic expressions. To make it possible, real-time communication should be established between the physical and digital twins. Empowered by modern Internet of Things (IoT) technology, many sensor signals can be transferred in a timely fashion to ensure real-time capability of the digital twin. The digital twin gives insightful information about its physical counterpart based on which smart decisions can be made to improve the design, prototyping, control, and lifecycle management of power electronics converters and systems. In this article, we review the digital twin of modern power electronics, and get an insight into its enabling technologies and possible applications.

Supercapacitor (SC) is an energy storage suitable for meeting short-term requirements in power conversion systems. However, the low and variable terminal voltage of SC-based energy storage poses challenges to the design of its power electronic interface (PEI) to achieve a high round-trip efficiency and a rapid response of the energy storage system. The PEI design methodologies existing in the literature do not clearly tackle the mitigation of switching and conduction losses over the entire operating range of the SC. This article proposes a design strategy for an SC-interface dual active bridge (DAB) converter. The terminal characteristics of the SC are incorporated into an analytical design formulation aiming to maximize the DAB efficiency over the SC discharging cycle. The resulting optimization problem, addressing both conduction and switching losses, is solved numerically to obtain the optimal circuit parameters. The realization of the design objectives and the obtained efficiency is validated in circuit simulation and experiments on a 250 W laboratory prototype with a 125 V dc bus and a nominal SC voltage of 37.5 V, illustrating the improvement achieved over the conventional design approach.

This article proposes a new control strategy for power electronic converters interfacing two dc networks. The proposed control, based on a modification of the dc virtual generator concept, has grid-forming capability in both sides of the converter simultaneously without intermediate energy storage device. Departing from the dc virtual generator control concept, capable of controlling voltage in one of the converter sides while withdrawing the power from the other side, an adaptation is done to make it reversible. A priority weight is assigned to each side voltage control. A weight calculation method, proportional to the voltage deviation from its rated value, is proposed. This weight calculation strategy makes the control system to contribute to the side most in need (using voltage deviation with respect to rated value as an indicator of the neediness). The interlinking converter with the proposed weighted strategy is capable of stable work in grid-forming mode at both sides simultaneously, just requiring a grid-feeding converter with $P/V$ droop to be connected in either side. No control architecture was found in the literature with this capability for dc–dc interlinking converters. The theoretical discussion has been supported with small-signal analysis and hardware-in-the-loop validation.

Talkative power conversion (TPC), which embeds information into the switching ripples of power converters to achieve the simultaneous transmission of power and data without the installation of additional hardware, can reduce the additional communication infrastructure in cyber–physical systems of digital energy and modern power plants. TPC in dc/dc converters has been the subject of numerous investigations, but comparatively few studies have focused on dc/ac converters. In this article, a novel variable zero-vector-width modulation (VZVWM) for three-phase dc/ac converters is proposed to achieve TPC. The dc/ac converters can transmit information to the receiver, crossing the LCL filter and power cable, with a good power quality. The harmonic distribution is mathematically analyzed, underpinning the viability of VZVWM-based TPC, and leading to the proposed sliding FFT-based demodulation. The electromagnetic interference (EMI) performance of the VZVWM-based talkative dc/ac converter is studied in detail. The correctness of harmonics distribution and feasibility of the VZVWM-based TPC is validated in simulations and experiments. Total harmonic distortion (THD) and bit error rate (BER) are evaluated with regard to variable cable distances, types, and zero vector’s widths.