Power Handling Research Articles

Impacts of material design on heat dissipation and power handling of acoustic-wave devices based on bonding wafers

Heat dissipation in surface acoustic wave (SAW) devices has never been researched in detail previously. With the arrival of the 5G era, more SAW devices with more complicated structures such as bonding wafers need to be integrated, easily leading to heat accumulation, so investigating heat dissipation in SAW devices is now necessary and urgent. Learning from the thermal-management researches in other fields and considering the mechanism and properties of SAW devices, this work believes that optimizing material design is efficient for heat dissipation enhancement. Therefore, this work for the first time systematically investigates the impacts of material design on heat dissipation and power handling which is significantly influenced by heat dissipation, building up a thermal-management theory for SAW devices based on bonding wafers. This work proposes a theoretical thermal calculation method for SAW devices, building a model and coding a calculation program. This work develops an experimental method by which the impacts of material design on heat dissipation can be deduced from those on power handling, designing and fabricating band-8 duplexers based on bonding wafers with different material designs. This work reveals that SiO2 and epoxy both weaken heat dissipation and impair power handling, while Si, sapphire, and SiC can all be chosen as heat-sink materials. Cost-efficient Si is quite proper for supporting substrates, and metal bumps are effective for thermal dissipation. This work gives guidance on enhancements of heat dissipation and power handling, helping researchers manage thermal properties in SAW devices and promoting the development of 5G communication.

Fivefold increased power handling in waveguide UTC-PDs using dual-injection shared CPW PD-arrays

This work presents two circuit-based solutions to enhance the power handling capabilities of waveguide-integrated uni-travelling carrier photodetectors (WG-UTC-PDs). Compared to a baseline WG-UTC-PD, these solutions achieve a fivefold increase in photocurrent before thermal breakdown. First, dual-injection improves the optical power distribution within a baseline WG-UTC-PD, raising the photocurrent threshold before thermal breakdown. Second, an array of four optically parallel WG-UTC-PDs, electrically connected to a single coplanar waveguide (CPW) line, further increases the maximum photocurrent by distributing the input optical power across multiple PDs. The design omits a termination resistor, as the arrays do not rely on a traveling wave configuration, maximizing photocurrent without a 50% reduction of bandwidth. Both 4-PD single-injection and dual-injection arrays were designed, fabricated, and characterized. Compared to a baseline UTC-PD, with a maximum photocurrent of 1.8 mA at a 3 dB bandwidth of 55 GHz, the 4-PD single-injection circuit achieved 5.1 mA at 43 GHz. The dual-injection array further increased the photocurrent to 9.2 mA at a bandwidth of 35 GHz. Electrical reflection measurements confirmed the negative effects of CPW losses on RF performance. These power handling improvements enable compact, high-power integrated solutions for microwave photonics.

Power handling in a highly-radiative negative triangularity pilot plant

Abstract This work explores detailed power handling solutions for a class of high-field, highly-radiative negative triangularity (NT) reactors based around the MANTA concept [Rutherford et al. (2024)]. The divertor design is kept as simple as possible, opting for a standard divertor with standard leg length. FreeGS is used to create an equilibrium for the boundary region, prioritizing a short outer leg length of only ∼50 cm (∼40% of the minor radius). The UEDGE code package is used for the boundary plasma solution, to track plasma temperatures and fluxes to the divertor targets. It is found that for PSOL = 25 MW and nsep = 0.96 × 1020 m−3, conditions consistent with initial core transport modeling, little additional power mitigation is necessary. For a fixed impurity fraction of just 0.13\% Ne in the plasma, the peak heat flux density at the more heavily loaded outer targets falls to 7.8 MW/m2, while the electron temperature, Te, remains just under 5 eV. Scans around the parameter space reveal that even at densities lower than in the primary operating scenario, PSOL can be increased up to 50 MW, so long as a slightly higher fraction of extrinsic radiator is used. With less than 1% neon (Ne) impurity content, the divertor still experiences less than 10 MW/m2 at the outer target. Design of the plasma-facing components includes a close-fitting vacuum vessel with a tungsten inner surface as well as FLiBe-carrying cooling channels fashioned into the VV wall directly behind the divertor targets. For the seeded heat flux profile, Ansys Fluent heat transfer simulations estimate that the outer target temperature remains at just below 1550◦C. Initial scoping of advanced divertor designs shows that for an X-divertor, detachment of the outer target becomes much simpler, and plasma fluxes to the targets drop considerably with only 0.01% Ne content.

Novel 4H–SiC MESFET with high ability in gate capacitances control for high frequency applications

The ability to control the gate capacitances is crucial for high-frequency applications, as it affects the device's frequency characteristics, gain and power handling capabilities. We present a 4H–SiC metal-semiconductor field-effect transistor (MESFET) with high gate capacitance control ability for high-frequency applications. The proposed structure (GCC-MESFET) consists of a step gate and a SiC well for adjusting the channel depletion layer and modifying the channel charges. Therefore, the gate capacitances will be controlled (GCC-MESFET). The proposed structure significantly improves the cut-off frequency (fT) and maximum oscillation frequency (fmax). The fT has increased from 23.5 GHz to 33 GHz and the fmax from 50.1 GHz to 54.4 GHz in the proposed structure compared to a conventional structure (C-MESFET). The results show that the DC maximum output power density (Pmax), DC transconductance (gm), cut-off frequency (fT) and maximum oscillation frequency (fmax) of GCC-MESFET improve in comparison with a conventional structure (C-MESFET). It is necessary to mention that the drain current and the breakdown voltage of the proposed structure increase by 48 % and 20 % respectively, compared with the C-MESFET structure due to modifying the channel charges and adjusting the electric field. So, the proposed structure can be used for high current, high voltage, high-power and high frequency applications.

Impact of repetitive ELM transients on ITER divertor tungsten monoblock top surfaces

Abstract Owing to the high stored energy of ITER plasmas, the heat pulses due to uncontrolled Type I edge localized modes (ELMs) can be sufficient to melt the top surface of several poloidal rows of tungsten monoblocks in the divertor strike point regions. Coupled with the melt motion associated with tungsten in the strong tokamak magnetic fields, the resulting surface damage after even a comparatively small number of such repetitive transients may have a significant impact on long-term stationary power handling capability. The permissible numbers set important boundaries on operation and on the performance required from the plasma control system. Modelling is carried out with the recently updated MEMENTO melt dynamics code, which is tailored to tackle melt motion problems characterized by a vast spatio-temporal scale separation. The crucial role of coupling between surface deformation and shallow angle heat loading in aggravating melt damage is highlighted. As a consequence, the allowable operational space in terms of ELM-induced transient heat loads is history-dependent and once deformation has occurred, weaker heat loads, incapable of melting a pristine surface, can further extend the damage.

Ku-band 300 kW high power ferrite phase shifter.

Phase shifter (PS) is a key component of a phased array antenna (PAA) system, which controls the microwave phase and realizes the antenna beam forming and scanning. A ferrite PS (FPS) is a current-controlled PS that uses the ferrite's gyromagnetic properties to realize phase shifting. It has the advantages of short phase switching time, low microwave loss, and high reliability and, therefore, has been widely used in low-power PAA systems. However, the power handling capability of the traditional Ku-band FPS is only a few kW, prohibiting FPS from being used in high-power microwave (HPM) PAA systems. Spurred by this concern, this paper proposes a new dual-toroid FPS structure with an external magnetic excitation. By optimizing the PS configuration, improving the integration process, and enhancing the performance of ferrite materials, a single FPS in the Ku band has reached the power handling capability of more than 300 kW with an insertion loss of less than -1.2 dB, the phase shift range of 0°-360°, the width less than 11.5mm, and the ability of a one-dimensional array. The FPS has the potential to be used in the PAA of an HPM system, laying a foundation for the research of the HPM PAA system.

NSTX-U research advancing the physics of spherical tokamaks

The objectives of NSTX-U research are to reinforce the advantages of STs while addressing the challenges. To extend confinement physics of low-A, high beta plasmas to lower collisionality levels, understanding of the transport mechanisms that set confinement performance and pedestal profiles is being advanced through gyrokinetic simulations, reduced model development, and comparison to NSTX experiment, as well as improved simulation of RF heating. To develop stable non-inductive scenarios needed for steady-state operation, various performance-limiting modes of instability were studied, including MHD, tearing modes, and energetic particle instabilities. Predictive tools were developed, covering disruptions, runaway electrons, equilibrium reconstruction, and control tools. To develop power and particle handling techniques to optimize plasma exhaust in high performance scenarios, innovative lithium-based solutions are being developed to handle the very high heat flux levels that the increased heating power and compact geometry of NSTX-U will produce, and will be seen in future STs. Predictive capabilities accounting for plasma phenomena, like edge harmonic oscillations, ELMs, and blobs, are being tested and improved. In these ways, NSTX-U researchers are advancing the physics understanding of ST plasmas to maximize the benefit that will be gained from further NSTX-U experiments and to increase confidence in projections to future devices.

(Invited) Ultrafast Spectroscopy of Nanostructured Plasmonic and Energy Conversion Materials

Ultrafast processes that occur upon the absorption of photons by a material frequently play important roles in the efficiency of a desired energy conversion or photocatalytic outcome. For example, energetic carriers produced upon photoexcitation of plasmonic systems can quickly dissipate energy through electron scattering processes on femtosecond timescales, followed by electron-phonon coupling on picosecond timescales. Once the carriers are thermalized, less energy is available to drive a charge separation or photocatalytic process. At the same time, there are number of handles with which to improve the efficiency of photoinduced processes, and ultrafast spectroscopy can be used to characterize that improvement. Nanostructuring, for example, can produce higher efficiency of photocatalytic processes as free charges are more likely to reach a surface following photoexcitation, and local anisotropies at the surface can drive electromagnetic field enhancements and the greater production of “hot” electrons. Hybridization of differing materials is also a powerful handle with which to manipulate or improve charge separation and photocatalytic outcomes. New materials can lead to greater robustness under illumination, as well as lead to changes in dissipation processes. In this talk, I describe recent efforts to characterize novel nanostructures of interest for plasmonics and energy conversion via ultrafast spectroscopy, as well as explore the ultrafast dissipation processes in refractory plasmonic nanomaterials. Particular attention is paid to dissipation of energy to the local environment of the nanoparticles as well as to ultrafast electron scattering processes. Hybrid nanostructures are also explored. Work performed at the Center for Nanoscale Materials, a U.S. Department of Energy Office of Science User Facility, was supported by the U.S. DOE, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.

Compact circular Wilkinson power divider for wireless applications

Abstract This manuscript introduces an innovative 1-to-4 modified Wilkinson power divider designed to operate at a frequency of 3.5 GHz. The configuration of the proposed divider is fabricated on Rogers RT/Duroid 5,880, featuring a relative permittivity of 2.2 and a thickness of 0.565 mm, respectively. The circular shape employed in the design minimises size and enhances power handling capability. To achieve a 4-way power division with equal power distribution at each output port, a 1:2 power divider at 3.5 GHz is cascaded. Furthermore, we present and analyse a 1:4 WPD implemented on a microstrip line utilised as a power supply for measuring a four-port MIMO antenna. This divider exhibits excellent impedance matching at all ports and consistent phase and amplitude characteristics between the output ports. The performance metrics of the presented divider, as detailed in both experimental and simulated results, include a return loss of 27.92 dB (1:2) and 29 dB (1:4), isolation of 33.046 dB (1:2) and 35.56 dB (1:4) and insertion loss of 3.17 dB (1:2) and 6.6 dB (1:4) respectively. These proposed power dividers hold potential applications in microwave and communication systems, mainly where power division is imperative with minimal signal loss and robust impedance matching.

Transfer functions for QA /QB international regulatory limits for the safe transport of radioactive materials

This paper presents a proposed revision of the International Atomic Energy Agency transport regulations, related to the A 1 and A 2 limit values used to determine the radioactive transport classification. Based on the ‘Q system’, a novel methodology was introduced to derive QA and QB values related to scenarios involving external exposure from a distant source. These values are key parameters that respectively represent the total effective dose and total equivalent dose to the skin, from all primary and secondary particles contributing to radiation exposure. The International Working Group (WG A 1/A 2) is established and associated with the TRANSSC Technical Expert Group on Radiation Protection. A review of the A 1 and A 2 values is performed in response to identified limitations within the existing Q system. The followed approach is based on Monte Carlo simulations that enabled the development of transfer functions aimed at reducing computational time and increasing the flexibility of dose evaluations for any radionuclide with known particle emission spectra. This method allows updating the QA and QB values to account for future data evolutions (decay data, fluence-to-dose conversion coefficients) and standardizing the calculation of regulation limits across all referenced radionuclides and scenarios related to external exposure. The transfer functions are established using three Monte Carlo simulation codes—FLUKA, Geant4, and MCNP—and address the previous limitations of the ‘Q system’, reflecting the latest International Commission for Radiation Protection recommendations and improvements in calculation techniques. The results of the WG show consistent agreement across the codes, with minor discrepancies observed at low primary energies due to statistical uncertainties and different handling of stopping power for electrons/positrons in the codes. This revised approach aligns with current standards and recommendations, ensuring that the radiological consequences of transport accidents are acceptable for the new A 1 and A 2 limits from a radiological protection perspective.

Bronchoscopy-Guided High-Power Microwave Ablation in an in vivo Porcine Lung Model.

Percutaneous microwave ablation (MWA) is clinically accepted for the treatment of lung tumors and oligometastatic disease. Bronchoscopic MWA is under development and evaluation in the clinical setting. We previously reported on the development of a bronchoscopy-guided MWA system integrated with clinical virtual bronchoscopy and navigation and demonstrated the feasibility of transbronchial MWA, using a maximum power of 60 W at the catheter input. Here, we assessed the performance of bronchoscopy-guided MWA with an improved catheter (maximum power handling of up to 120 W) in normal porcine lung in vivo (as in the previous study). A total of 8 bronchoscopy-guided MWA were performed (n = 2 pigs; 4 ablations per pig) with power levels of 90 W and 120 W applied for 5 and 10 min, respectively. Virtual bronchoscopy planning and navigation guided transbronchial or endobronchial positioning of the MWA applicator for ablation of lung parenchyma. Following completion of ablations and post-procedure CT imaging, the lungs were harvested and sectioned for gross and histopathologic ablation analysis. Bronchoscopy-guided MWA with applied energy levels of 90 W/5 min and 120 W/10 min yielded ablation zones with short-axis diameters in the range of 20-28 mm (56-116% increase) as compared to ∼13 mm from our previous study (60 W/10 min). Histology of higher-power and previous lower-power ablations was consistent, including a central necrotic zone, a thermal fixation zone with intact tissue architecture, and a hemorrhagic periphery. Catheter positioning and its confirmation via intra-procedural 3D imaging (e.g., cone-beam CT) proved to be critical for ablation consistency. Bronchoscopy-guided MWA with an improved catheter designed for maximum power 120 W yields large ablations in normal porcine lung in vivo.

High performance power handling in the absence of an H-mode edge in negative triangularity DIII-D plasmas

Experiments performed during strongly-shaped high-power diverted negative triangularity (NT) experiments in DIII-D achieved detached divertor conditions and a transient-free edge, showcasing the potential for application of NT to a core-edge integrated reactor-like scenario and providing the first characterization of the parametric dependencies for detachment onset. Detached divertor conditions will be required in future devices to mitigate divertor heat fluxes. Access to dissipative divertor conditions was investigated via an increase in upstream density. Detachment onset at the outer strike point was achieved with H-mode level confinement H98−y2∼1 and reactor-relevant normalized pressures βN∼2 . Confinement degradation was observed with deeper detachment, associated with the loss of an electron temperature pedestal. Differences in geometry, radial transport, impact of cross field drifts are discussed to explain differences in access to detachment in NT discharges. Higher normalized densities, with respect to equivalent discharges in positive triangularity, were necessary to achieve detachment, partially explained by the shorter parallel connection length to the targets. The effect of cross-field particle drifts (E×B, B ×∇ B) on access to detachment was demonstrated by the lower upstream density needed to access detachment with ion B ×∇ B drift directed outside of the active divertor (Greenwald fraction fGw∼ 0.9–1.0 vs fGw∼ 1.3). The upstream density at detachment onset was observed to increase linearly with plasma current with ion B ×∇ B drift into the divertor, consistent with the observed narrowing of the scrape-off layer heat flux width λ q . Edge fluid simulations capture separatrix densities needed to achieve detachment in NT plasma and their dependence on drift direction. The ability to reproduce detachment dynamics in NT plasma increases the confidence in future design studies for NT divertors.

Optimisation of the poloidal field system for advanced divertor configurations in STEP

The power exhaust proves to be one of the most challenging and concept–defining aspects in the design of a commercial fusion power plant, while the magnetic coil system, capable of supporting advanced exhaust solutions, emerges as one of the main design and cost drivers. Consequently, much effort should be dedicated to the optimisation of a robust global magnetic configuration, which integrates both the plasma and edge scenarios, while ensuring engineering feasibility and compatibility with the available technology. Here we present a multidisciplinary framework employed to analyse, evaluate, and optimise the Spherical Tokamak for Energy Production (STEP) equilibrium configuration, coupled with a viable divertor solution, and a compatible poloidal field coil system. The complexity of this task leads to a multitude of potentially conflicting requirements and competing constraints. We identify interfaces and conflicts between the aspects of the design that were previously considered independently, and highlight the key benefits, trends, and trade–offs between alternative configurations. We demonstrate that advanced exhaust solutions, simultaneously applied to both inboard and outboard divertors, are accessible with feasible coil sets under conditions relevant for STEP. We show that the most promising inner–X geometry, paired with the outer super–X configuration, can significantly enhance divertor’s power handling capability, allowing access to stable detached regimes. The coil set feasibility is further assessed considering its compatibility with the assumed plasma initiation scenario, and with the most demanding plasma current density profiles utilising alternative heating and current drive schemes.

High power, broadband, coaxial to microstrip bi‐directional coupler in the VHF/UHF band

AbstractBroadband couplers consist usually of multiple coupled lines that are each a quarter wave‐length long. Herein, in contrast to conventional methods, a short length of a microstrip line is coupled to a coaxial line. The length of the coupled microstrip line is small compared to the wavelength at the lowest operating frequency. The coupling is weak and the microstrip line is λ/8 at the highest operating frequency. The proposed structure resembles a pair of coupled lines with a linear coupling response. The coupling exhibits a slope of 6 dB/octave over multi‐octave bandwidth. The microstrip line is connected to a lumped element compensating network at the coupled port. The compensating network is a low‐pass circuit with a slope of −6 dB/octave. The power handling of the coupler is high due to the coaxial line and the weakly coupled microstrip line. Electromagnetic simulations and analytical formulations are presented. The broadband coupler handles nearly 1 kW of input power. Due to the weak coupling of the microstrip‐coaxial coupler, the lumped element circuit needs to handle <1.5 W. A high‐power coupler has been fabricated for the frequency range of 30 to 500 MHz. It exhibits a coupling response of 56 ± 0.4 dB.

Harmonic modelling and control of dual active bridge converter for DC microgrid applications

Due to the intermittent power availability from renewable sources, the bidirectional DC-DC converter (BDC) must integrate with the energy storage system for bidirectional power flow. Among many BDCs, the Dual Active Bridge (DAB) converter is the most promising because of the system's power handling capacity and efficiency. DAB bidirectional DC-DC converter is a topology with the advantages of a decreased number of devices, soft-switching commutations, low cost, and high efficiency. This work describes the guidelines for designing a DAB converter for small DC microgrid applications. It is shown that the judicial selection of reactive elements leads to soft switching for all the switches in the converter in varying load conditions. A guideline for the controller design is given and the operations are validated through the simulation. A harmonic modelling technique has been implemented to model the DAB converter based on an efficient closed-loop regulator. A solar PV system has also been implemented here with a SEPIC converter that is used as an interfacing element between the PV system and the load bus. At last, a DC Microgrid is simulated in a PSIM environment to showcase its various modes of operation. It is shown that the battery bank can support variable loads independently through the DAB converter. In inadequate solar power generation, load power demand is shared between the battery and PV system. In case of deep discharge of the battery, the PV system can charge the battery through a DAB converter.

Dual-Module Ultrawide Dynamic-Range High-Power Rectifier for WPT Systems

Rectifier plays a pivotal role in wireless power transfer systems. While numerous studies have concentrated on enhancing efficiency and bandwidth at specific high-power levels, practical scenarios often involve unpredictable power inputs. Consequently, a distinct need arises for a rectifier that demonstrates superior efficiency across a broad range of input power levels. This paper introduces a high-power RF-to-DC rectifier designed for WPT applications, featuring an ultrawide dynamic range of input power. The rectification process leverages a GaN (gallium nitride) high electron mobility transistor (HEMT) to efficiently handle high power levels up to 12.6 W. The matching circuit was designed to ensure that the rectifier will operate in class-F mode. A Schottky diode is incorporated into the design for relatively lower-power rectification. Seamless switching between the rectification modes of the two circuits is accomplished through the integration of a circulator. The proposed rectifier exhibits a 27.5 dB dynamic range, achieving an efficiency exceeding 55% at 2.4 GHz. Substantial improvement in power handling and dynamic range over traditional rectifiers is demonstrated.

A high‐power coaxial to rectangular waveguide transition

AbstractThe high‐power characteristic of the coaxial to waveguide transition plays an important role in modern communication and radar systems. In this letter, a novel design of a high‐power transition from a 50 Ω coaxial line with an N‐type connector to a WR‐90 rectangular waveguide. The power handling capability (PHC) of the proposed structure is significantly enhanced by a cone‐shaped excitation probe with a bold end, a transitional cavity, and a mode conversion cavity with a curved shorted back wall. The simulated results reveal that the transition possesses high PHC of 257 kW at 8.5 GHz, which is the upper limit of the power tolerance for the N‐type connector. The measured results show that the return loss and insertion loss are better than 15 and 0.15 dB, respectively, in the range of 7.96–9.16 GHz. In addition, experimental validation confirms the normal operation of the structure under a 250 kW power level test, demonstrating the applicability of the proposed transition in high‐power microwave systems.

Comparative Analysis of 5-Level and 7-Level Single-Phase Cascaded H-bridge Multilevel Inverters

The demand for high-performance, efficient, and reliable power electronic systems has been steadily increasing in various industrial applications, including renewable energy systems, electric vehicles, and smart grids. In response to this demand, the Cascaded H-Bridge Multi-level Inverter (CHB-MLI) has emerged as a promising solution, offering advantages such as improved voltage waveform quality, reduced harmonic distortion, and enhanced power handling capabilities. The CHB-MLI is characterized by its modular structure, comprising multiple H-bridge cells cascaded in series. Each H-bridge cell operates with a separate DC power source, enabling the generation of stepped voltage levels at the inverter output. By intelligently controlling the individual H-bridge cells, the CHB-MLI achieves the synthesis of a high-quality multilevel output voltage waveform. The different multi-level inverter topologies are Diode-Clamped MLI, Capacitor-Clamped MLI and Cascaded H-bridge MLI. This paper focused on key aspects like design, simulation, control strategies, performance evaluation, overall comparison and analysis of 5-level and 7-level CHB-MLIs. By addressing these aspects, this paper aimed to contribute to the advancement of power electronics technology and promote the adoption of the CHB-MLI in real-world applications, fostering energy efficiency and sustainability in power conversion systems. Index Terms: Inverter, Multi-level inverter, CHBMLI, switching, SPWM, MCSPWM, gate signal, waveform, harmonics, THD, MATLAB.

A practical introduction to radio frequency electronics for NMR probe builders

In this tutorial paper, we describe some basic principles and practical considerations for designing probe circuits for NMR or MRI. The goal is building a bridge from material that is familiar from undergraduate physics courses to more specialized information needed to put together and tune a resonant circuit for magnetic resonance. After a brief overview of DC and AC circuits, we discuss the properties of circuit elements used in an NMR probe and how they can be assembled into building blocks for multi-channel circuits. We also discuss the use of transmission lines as circuit elements as well as practical considerations for improving circuit stability and power handling.

Optimal number of supercapacitors per submodule in the energy storage system based on a modular multilevel converter with embedded balance control

As renewable energy sources interconnected to the electric grid increase, deploying distributed energy storage systems along the grid is a viable solution to sustain grid stability. One of the critical aspects of any energy storage system is its efficiency in transferring power to the grid. Another important aspect is managing high power levels in a short time and being easily expandable in terms of energy capacity and power handling. For this reason, supercapacitors are suitable energy storage devices to fulfill these requisites. This article focuses on analyzing the losses and improving the efficiency of a supercapacitor energy storage system based on a modular multilevel converter, which accomplishes all the abovementioned functions and capabilities. The analyzed energy storage system is based on submodules, including the power electronic interface and the supercapacitors. Hence, the system can be easily expanded because the submodule provides the functions of balancing the energy storage devices, the DC/AC, and the DC/DC conversions by using the modular multilevel converter topology approach. Therefore, any number of submodules can be connected, and the operator can make an array of the desired power, energy, and voltage ratings. This study details a probabilistic loss analysis for the proposed supercapacitor energy storage system and presents a case study using 3000F supercapacitor cells for a 6.6 kW single-phase system. The improved submodule version is validated through simulations and experimentally with a lab-scale prototype. The results show how the proposed methodology increases the system's overall efficiency with a 95 % confidence level.