Power Electronic Components Research Articles

Local adaptive insulation in amorphous powder cores with low core loss and high DC bias via ultrasonic rheomolding

Amorphous powder cores are promising components for next-generation power electronics. However, they present inherent challenges of internal air gaps and stresses during cold compaction, which significantly deteriorate soft magnetic properties. Here, we report the formation of a local adaptive insulation structure of biconcave lens in amorphous powder cores by ultrasonic rheomolding. Consequently, compared with conventional cold-compacted powder cores, the ultrasonic rheomolded powder cores offer significant simultaneous improvements in the permeability from 31.3–32.4 to 41.8–43.3 and the direct-current bias performance from 69.4–69.7% to 87.4–87.8% (7960 A/m), thereby overcoming the trade-off between permeability and direct-current bias performance. In particular, their core losses are as low as 13.73–15.45 kW/m3, approximately one twentieth of that of the cold-compacted powder cores (282.84–304.03 kW/m3) at a magnetic field of 100 mT and 100 kHz. The biconcave-lens insulation structure can effectively buffer the impact of high mechanical stress on the magnetization of magnetic powder particles, allowing for the ultrasonic rheomolded powder cores to maintain better magnetization efficiency and consequently resulting in excellent soft magnetic properties under the cooperative effect of very low internal stresses and low porosity. The ultrasonic rheomolded powder cores can be used as alternative core components in next generation miniaturized power electronics.

Remarks on High-Frequency Electromagnetic Field Analysis of Magnetic Components for Power Electronics

Remarks on High-Frequency Electromagnetic Field Analysis of Magnetic Components for Power Electronics

High performance Calcium Copper Titanate/Polyimide dielectrics composites enabled through colloidal stabilization

AbstractTransition to electrified transportation demands advanced power electronic components with the capability to improve range, reliability, and cost of ownership to accelerate mass market adoption. Thus, improvement in the current designs, manufacturing processes, materials, and components capable of providing reliable and efficient operation at higher temperatures play important roles in meeting future needs. To address these challenges, this article focuses on novel dielectric materials designed to reduce the volume of the most important and bulky component of a power electronic system, a capacitor. A new composite dielectric material was developed by integrating the positive attributes of both polymer and ceramic capacitors to overcome the challenges of state‐of‐the‐art dielectric materials. The developed composite properties have been evaluated and showed promising results, achieving a dielectric constant of 250 at 100 Hz, 25°C, unseen in current literature. Additionally, these materials can function at high temperatures (>150°C) with good breakdown strength, providing promising working conditions for capacitors, especially in electric vehicle applications.Highlights Dielectric composites were synthesized from calcium copper titanate and polyimide. A dispersive agent showed promise in achieving a homogenous, stable mixture. Composites were prepared using tape casting. A dielectric constant of 250 was achieved at 100 Hz, 25°C. At elevated temperature, the dielectric constant increased to over 700%.

Comparison of active and passive vibration control techniques for electric drive power electronic subsystem: Experimental validation

Reducing vibration and noise from power electronics components is vital for enhancing the performance and acceptance of electric vehicles, emphasizing the need for effective mitigation strategies in sustainable transportation. This paper compares passive and active vibration techniques, with a specific focus on utilizing particle damping for passive vibration control. The method achieves vibration reduction through viscoelastic deformation and friction resulting from the movement and collisions of granular material within the cavity. This contribution outlines diverse design strategies for integrating particle dampers into power electronic components. The active control approach, operating typically in the 50 Hz to 1200 Hz frequency range, can concurrently support passive noise treatments. Piezoelectric ceramics serve as both actuators and sensors in active noise reduction. Following the identification of dominant mode shapes, appropriate actuator and sensor positions are chosen. The control problem of the smart system is then addressed, opting for a velocity feedback control algorithm in a real collocated design. This algorithm computes input signals for actuators bonded to the outer surface, achieving significant active damping effects. Lab-tested techniques are validated in real-world conditions with a full-scale electric-drive toolkit, affirming their efficacy in reducing vibration and noise and underscoring their potential for implementation in electric vehicles.

Asymmetric Multilevel DC Link inverter for Reducing THD using a Meta-Heuristic Algorithm

Multilevel inverters are essential for increasing power quality, boosting efficiency, and lowering harmonic distortion in the field of power electronics. This research presents a new method using the Pelican optimization algorithm (POA) to create pulse patterns in multilevel inverters. The work focuses on deploying a 125-level asymmetric multi-level inverter that is powered by solar panels through a Dc-Dc converter in order to address power quality difficulties. In order to get better performance in multilevel inverter systems, the Pelican optimization algorithm is used to create pulse patterns that are modeled after the hunting strategies of pelicans. The Distributed Static Synchronous Compensator, is a leading device that uses power electronic components to control power flow and improve power quality in power grids. It is one of the many specialized power devices available. The primary objective is to enhance reactive power to ensure the stability of voltage within the power system and the aim of this research is to maintain voltage stability. Using the pelican optimization algorithm, the method entails creating and deploying a DSTATCOM based on a 125-level asymmetric multi-level inverter.

Theoretical and experiment optimization research of a frequency up-converted piezoelectric energy harvester based on impact and magnetic force

Harvesting environmental vibrations to power electronic components is an essential approach for addressing the power supply challenge in MEMS. However, conventional vibration energy harvesting systems frequently suffer from limited frequency bandwidth and high-frequency deficiencies. This paper proposes a novel up-frequency structure for piezoelectric vibration energy harvesting (VEH) that relies on both nonlinear magnetic force and piecewise linear force. The proposed VEH’s nonlinear dynamic characteristics are analyzed theoretically, and an experimental prototype machining and vibration test platform are constructed. Theoretical and experimental results are compared and analyzed by conducting basic experiments and key parameter optimization experiments. The research results demonstrate that the proposed VEH can efficiently harvest vibration energy in low-frequency and wide-band environments. Regarding the system parameters, higher vibration acceleration results in increased output voltage and wider working frequency bandwidth. Reducing the gap distance enhances piecewise linear vibration, which broadens the working frequency bandwidth. Furthermore, the proposed VEH’s ability to harvest low-frequency vibrations can be enhanced by reducing the magnet distance, thereby reducing the linear resonance frequency of the system. The findings of this study offer valuable insights for advancing the engineering application of MEMS self-power supply technology.

Research on load-resistant enhancement control optimization of composite energy power supply system based on deep reinforcement learning

Abstract To solve the problem of insufficient inertia in the power electronics components under the development trend of power electronics in the transmission system of heavy-duty electric vehicles, combined with the composite energy power supply mode and control method, voltage-based feedback channels and virtual capacitor branches are designed for both engine-generator sets and DCDC control loops. These innovations compensate for system inertia and introduce a TD3 deep reinforcement learning-based adaptive regulation component to manage electrical systems in response to DC voltage fluctuations. This approach enhances the stability of the entire system in the face of load disturbances. Strategy validations demonstrate that this method ensures stable system operation, significantly mitigates DC voltage fluctuations during sudden load changes and is highly adaptable without relying on system models.

Research on simulation accuracy of equivalent aggregate electromagnetic model optimization for large renewable energy stations

Abstract The traditional power grid is rapidly transforming into a new power system with high penetration of new energy. Simulation modeling plays an important role in supporting the cognition and research of the new power system. A high proportion of renewable energy is connected to the grid through power electronic components, which puts forward a higher demand for research on the accuracy and stability of power grid simulation modeling. Renewable energy plants usually have a large number of single units, and equivalent aggregation modeling is the usual way to simplify the modeling of renewable energy plants. However, the transmission line power multiplier equivalent module inevitably introduces series impedance into the network, resulting in errors between simulation and actual engineering. Therefore, the study of lossless multiplier elements based on Modified Nodal Analysis (MNA) can improve the simulation accuracy, and it is verified with the simulation results of detailed models in actual scenarios, proving that MNA lossless multiplier elements can optimize the accuracy and stability of equivalent aggregation modeling of large-scale multi-unit renewable energy stations.

Symmetrical Multilevel High Voltage-Gain Boost Converter Control Strategy for Photovoltaic Systems Applications

This paper proposes a Symmetric High Voltage-Gain (SHVG) boost converter control for photovoltaic system applications. The concept is based on a multilevel boost converter configuration, which presents an advantage compared to a classic boost converter such as the ability to transfer a high amount of power with less stress on the power electronics components in the high voltage-gain conditions. This advantage allows the power losses in the converter to be reduced. A mathematical-based voltage model of the PV system using variable series resistance depending on solar irradiance and the temperature is proposed. This model is connected to an SHVG boost converter to supply the load’s power. A control strategy of the DC-bus voltage with maximum power point tracking (MPPT) from the PV system using PI controllers is developed. The contributions of the paper are focused on the SHVG operating analysis with the passive components’ sizing, and the DC-bus voltage control with maximum power point tracking of the PV systems in dynamic operating conditions. The performances of the proposed control are evaluated through simulations, where the results are interesting for high-power photovoltaic applications.

Thermal Resistance Modeling for the Optimal Design of EE and E/PLT Core-Based Planar Magnetics

With the integration of power electronic converters and components, an accurate thermal design becomes essential. Hence, precise thermal models for components are needed for their optimal design. This paper focuses on the development of an analytical model for the design of thermal resistance of planar magnetic cores (PMC). Based on computational fluid dynamic (CFD) simulations, the PMC design thermal resistance variation is studied, according to ambient temperature and level of losses. Then, a polynomial equation is developed to model those variations, and coefficients are deduced for all the sizes of PMC. This analytical model, useful for designers, is finally validated with thermal measurements on a planar transformer prototype.

Review of semiconductor devices and other power electronics components at cryogenic temperature

Review of semiconductor devices and other power electronics components at cryogenic temperature

Lead‐Free High Permittivity Quasi‐Linear Dielectrics for Giant Energy Storage Multilayer Ceramic Capacitors with Broad Temperature Stability

AbstractElectrostatic energy storage capacitors are essential passive components for power electronics and prioritize dielectric ceramics over polymer counterparts due to their potential to operate more reliably at > 100 ˚C. Most work has focused on non‐linear dielectrics compositions in which polarization (P)/electric displacement (D) and maximum field (Emax) are optimized to give values of energy density, 6≤U≤21 J cm−3. In each case however, either saturation (dP/dE = 0, AFE) or “partial” saturation (dP/dE → 0, RFE) of P limits the value of U which can be achieved before breakdown. It is proposed that U can be further improved with respect to relaxors (RFEs) and anti‐ferroelectrics (AFEs) by designing high permittivity quasi‐linear dielectric (QLD) behaviour in which dP/dE remains constant up to ultrahigh Emax. QLD multilayer capacitor prototypes with dielectric layers composed of 0.88NaNb0.9Ta0.1O3‐0.10SrTiO3‐0.02La(Mg1/2Ti1/2)O3 deliver room temperature U ≈ 43.5 J cm−3, supporting an extremely‐large Emax ≈ 280 MV m−1, both of which exceed current state‐of‐art by a factor of two for devices based on powder, tape‐cast technology. Importantly QLD capacitors exhibit scant variation in U (≈15 J cm−3) up to > 200 ˚C and robust resistance to cyclic degradation, offering a promising new approach for the development of sustainable technology.

Assessment of the state-of-the-art of solid-state transformer technology: design, control and application

The structure and principle of operation of conventional iron-and-copper conventional transformers has not changed for the past decades largely to its high efficiency and reliability. However, conventional transformers are generally heavy and limited to transformation of AC power only in a unidirectional pattern. However, due to the increasing integration of distributed generation to grid, bidirectional power flow within the present grid systems is now inevitable. This makes solid-state transformer (SST), as a more flexible, portable, and cost-effective alternative, to gain considerable attention in recently. The SST is designed using power electronic components and a high frequency transformer (HFT). As an energy router, SST is crucial to the deployment of internet energy system due to its compact size, improved controllability, resiliency, bidirectional power flow, and variety of applications. Various designs and control approaches have been proposed for the SST to suit various applications. Thus, this paper reviews the extent of research works carried out on the SST vis-à-vis classifications, design, control and applications. The review is centered on establishing the state-of-the-art and identify future research prospects in the design, control, and applications of SST.

Thermal analysis of an integrated motor drive with a switching cell array power converter

In modern electric propulsion systems the electric motor is tightly integrated with the power converter and control unit. These so called Integrated Motor Drives can allow for vast improvements in efficiency and volume reduction, due to the elimination of redundant electric components, and the shared case and cooling system between the motor and the power converter. The cooling systems used in these applications must be carefully designed as the motor and power electronics components may feature greatly different temperature limits. This work discusses the development of a thermal model for an integrated motor drive composed by a six phase permanent magnet motor with hairpin windings and a switching-cell-array-based multilevel power converter. The system is modelled by means of a lumped parameter thermal network which includes an accurate model of the motor stator and rotor, as well as the arrangement of the power switches on the converter boards. The conductive resistances are simply obtained from geometric data and material properties. Instead, the convective resistances are evaluated by means of empirical models available in the literature and a CFD model for the cooling jacket. The developed model is employed to assess the feasibility of the presented arrangement of motor and power electronics components from the thermal point of view.

Modeling a Solenoid Driver with Nonlinear Inductive Load Using Circuit Simulation and Magnetic Flux Measurement

This paper describes the procedure for creating a electronic simulation model of a solenoid power electronic driver with a nonlinear inductive load. Furthermore, it discusses the electromagnetic interaction between the driver and the load example electromagnetic valve. The consideration of nonlinear effects in the power electronic components MOSFET and diode is particularly important to distinguish their effects from the nonlinear behaviour of the inductive load.

A novel electro-hydraulic unit design based on a shaftless integration of an internal gear machine and a permanent magnet electric machine

In recent years, increasingly stringent emission regulations have spurred an electrification trend in off-highway vehicle technology. To address challenges such as the high cost of power electronics components, limited battery capacity, and the substantial modifications required for the vehicles, there is a pressing need to develop high-speed, cost-effective, compact, and efficient electro-hydraulic units capable of powering vehicle functions. In response to these demands, this paper introduces an innovative morphology for an electro-hydraulic unit and outlines the integration method for a crescent-type internal gear machine with a permanent magnet synchronous electric machine. The proposed morphology aims to minimize component count through a shaftless solution while incorporating a cooling system that utilizes the same working fluid as the hydraulic machine. The design approach utilizes a genetic algorithm optimization process to maximize overall energy efficiency and compactness. Insights gained from the optimization results shed light on the relationship between key design parameters and unit performance, enhancing the understanding of this electro-hydraulic unit. A prototype of the unit was manufactured and tested, demonstrating a volumetric efficiency ranging from 81 % to 97 % at a maximum rotational velocity of the pinion of 6000 rpm. These results validate both the morphology and the design approach, indicating the feasibility of designing compact electro-hydraulic units that leverage hydraulic machines with higher maximum rotational velocities than commercially available counterparts as a mean to enhance efficiency and compactness.

Impact of Chaos on MOSFET Thermal Stress and Lifetime

The reliability of power electronic switching components is of great concern for many researchers. For their usage in many mission profiles, it is crucial for them to perform for the duration of their intended lifetime; however, they can fail because of thermal stress. Thus, it is essential to analyze their thermal performance. Non-linear switching action, bifurcation and chaotic events may occur in DC-DC power converters. Consequently, they show different behaviors when their parameters change. However, this is an opportunity to study these bifurcation phenomena and the existence of chaos, e.g., in boost converters, on their performance as the effects of load variations (mission profiles) on the system’s behavior. These variations generate many non-linear phenomena such as periodic behavior, repeated period-doubling bifurcations and chaos in the MOSFET drain-source current. Thus, we propose, for the first time, an analysis of the influence of chaos on the junction temperature. First of all, this paper provides a step-by-step procedure to establish an electrothermal model of a C2M0080120D MOSFET with integrated power loss. Then, the junction temperature is estimated by computing the power losses and a thermal impedance model of the switch. Additionally, this model is used to investigate the bifurcation and chaotic behavior of the MOSFET junction temperature. The paper contributes by providing a mathematical model to calculate several coefficients based on experimental data and thermal oscillations. Estimation of the number of cycles to failure is given by the Coffin–Manson equation, while temperature cycles are counted using the rainflow counting algorithm. Further, the accumulated damage results are calculated using the Miner’s model. Finally, a comparison is made between the damage accumulated during different mission profiles: significant degradation of the MOSFET’s lifetime is pointed out for chaotic currents compared to periodic ones.

Enabling magnetic pulse welding for dissimilar tubular arrester cable joints

Climate change exacerbates the need for resource-efficient and cost-effective production processes across manifold industries, including the field of electrical connections. This specific field is characterized by a conflict of objectives, i.e., weight reductions while maintaining joint strength and electrical conductivity. From a material point of view, the use of aluminum as a conductor material is suitable for this application, as it is lighter than copper, a classical conductor material. Electrical conductors are often used in the form of flexible cables, so-called stranded wires. This type of conductor as well as the fact that the sole use of aluminum in electrical systems is not feasible, e.g., because the predetermined connection terminals of power electronic components are made of copper, creates a substantial demand for dissimilar aluminum-copper cable arrester joints. However, traditional fusion-based welding processes have proved incapable of reliably producing these dissimilar aluminum-copper joints because of thermophysical effects and chemical incompatibilities, the latter eventually leading to the formation of intermetallic phases. These phases adversely affect the quality of the joint in terms of both mechanical and electrical performance. Yet, magnetic pulse welding, a pressure welding process, is ideally suited for producing dissimilar metal joints on the basis of a low energy input during the welding process. Consequently, the formation of intermetallic phases is restrained. However, magnetic pulse welding has not been sufficiently investigated for the reliable contacting of stranded cables to tubular arresters. As a result, this paper focuses on the fabrication of tubular stranded cable arrester joints using magnetic pulse welding. To shed light on possible material combinations, aluminum-to-aluminum and copper-to-copper joints as well as their dissimilar counterparts are welded. Subsequently, the joints are characterized with regard to their microstructure and quasi-static material strength. Electrical characterization comprises the four-wire Kelvin measurement method to evaluate the resistance of the electrical joints. The results demonstrate that magnetic pulse welding is ideally suited to join the aforementioned material combination and joint configuration due to its process characteristics eventually leading to material continuity. As a result, the stranded wires are welded to the tubular arresters rather than crimped. Consequently, a comparative analysis of the joint properties with those of the joining partners shows that the measured electrical resistances and mechanical tensile forces may be considered very good.

SISTEM AVANSAT DE ÎNCĂRCARE WIRELESS DE MARE PUTERE CU TRANSFORMATOR ELECTRONIC PENTRU VEHICULE ELECTRICE

"The rapid transition from internal combustion engine (ICE) vehicles to electric vehicles (EVs) is accompanied by many technical and economic challenges. One is related to the improvements the power distribution grid requires due to the increasing number of charging power stations, which will require important investments and improvements. A promising technology that may contribute to these improvements is the solid-state transformer (SST), which could be used to replace the classical distribution transformers. Such an SST is made of complex power electronics components and is more flexible than the classical transformers, being able to regulate easily the voltage and frequency in the secondary circuit. This paper is focused on the numerical simulation of a flexible high-power wireless charging system that may be used for heavy-duty and commercial electric vehicles. The numerical computations are carried out using Matlab/Simulink environment and allow us to estimate the performance of such complex systems."

A Modular Multilevel Converter-Shunt Active Power Filter-Based Hybrid Topology for Grid Power Quality Improvement

With the increasing penetration of renewable energy sources and active loads into the electrical power system, the limitations of traditional low-frequency power grids are becoming apparent. The solid-state transformer (SST), with its multiple conversion stages offering various power ports, is an innovative solution to these challenges. However, the high cost of the SST, due to its heavy reliance on power electronic components, makes the complete replacement of traditional grids an economically nonviable option. Therefore, this paper proposes a parallel connection of the SST to an existing traditional power grid in order to divide the transmitted power, thus reducing the investment costs. Furthermore, a hybrid topology based on modular multilevel converter (MMC) and shunt active power filter (SAPF) is proposed in this paper in order to compensate the harmonic currents caused by non-linear loads while maintaining steady energy delivery. Additionally, an artificial neural network (ANN) controller is adopted for the MMC output DC voltage control to ensure a regular DC-link voltage for both the SAPF and the DC-to-DC converter of the SST. The proposed topology is implemented and evaluated in MATLAB/Simulink software, and various simulation results are presented.