A5077225839- Microgrid Control and Optimization
- Multilevel Inverters and Converters
- Advanced DC-DC Converters
- Islanding Detection in Power Systems
- HVDC Systems and Fault Protection
- Electric Motor Design and Analysis
- Sensorless Control of Electric Motors
- Power Systems Fault Detection
- Photovoltaic System Optimization Techniques
- Power Systems and Renewable Energy
- Silicon Carbide Semiconductor Technologies
- Smart Grid Energy Management
- Energy Harvesting in Wireless Networks
- Advanced Battery Technologies Research
- Optimal Power Flow Distribution
- Induction Heating and Inverter Technology
- Electrostatic Discharge in Electronics
- Machine Fault Diagnosis Techniques
- Electromagnetic Compatibility and Noise Suppression
- Electrical Fault Detection and Protection
- Parallel Computing and Optimization Techniques
- Electric Power Systems and Control
- Electric and Hybrid Vehicle Technologies
- Advanced Aircraft Design and Technologies
- Distributed and Parallel Computing Systems
Georgia Institute of Technology
2021-2025
Kansas State University
2017-2020
Simón Bolívar University
2017
Universidad Simón Bolívar
2015
The main purpose of this article is to provide an instructive review the technological challenges hindering road toward more electric powertrains in aircraft. Hybrid, all-electric, and turboelectric powertrain architectures are discussed as possible fuel consumption weight reduction solutions. Among these architectures, short-term implementation hybrid all-electric limited, particularly for large-capacity aircraft due low energy/power density levels achievable by state-of-the-art electrical...
This article introduces a signal reformation-based direct phase-angle detection (DPD-SR) technique for three-phase inverters supporting asymmetrical grids. Asymmetries in systems may happen because of unbalanced loads, which can lead to the voltage asymmetry at terminals grid-tied inverters. The proposed DPD-SR detect phase angle under conditions. also offers precise and rapid through reformation trigonometric functions. In essence, is directly derived from properties line–line voltages,...
Grid-forming (GFM) inverters, like synchronous generators (SGs), form voltage at their terminals and are considered crucial for enabling high renewable energy integration. Most GFM controllers mimic the power-synchronization characteristics of SG rotor's swing dynamics to synchronize with system. However, inverters differ significantly from SGs in both design control. This paper systematically explores these differences. The analysis reveals that coupling between steady-state transient...
In a more electric aircraft (MEA) design, the onboard generators are mechanically coupled directly to jet engines, thus producing variable-frequency constant magnitude voltage. This wild-frequency characteristic imposes new design challenge on power converters. this article, an experimental performance comparison between model predictive and proportional-integral (PI)-based control schemes for active rectifiers in MEA applications is presented. The of aforementioned controllers executed...
The modern power grid is one of the greatest achievements engineering, an intercontinental scale machine with thousands generators and millions customers interconnected by miles passive transmission distribution network. foundation society, we take it for granted. When considers that basic principles operation have not changed in over 100 years these were formulated era before microprocessors digital controls, begin to appreciate importance rules govern system behavior.
A parameter estimation method for deep-bar induction machines is presented. The parameters are estimated using two instantaneous voltage and current waveforms during a direct startup. input impedance used as stator indicator to solve constrained nonlinear optimization problem that outputs the model's parameters. For such purposes, novel analytical expression introduced. validated in distinct National Electrical Manufacturers Association (NEMA) design type (designs B), accuracy of obtained...
Permanent magnet synchronous generator (PMG) based direct-drive wind turbines (DDWTs) have recently drawn the attention of power market given their low operation and maintenance cost, reliability, longer lifetime. In this paper, a zero dc-link impedance topology for DDWT-PMG systems is presented. The proposed eliminates use failure-prone dc bus capacitor by replacing grid-side converter with phasor pulse-width modulation (PPWM) boost current source inverter (CSI), also referred to as...
Standards and specifications for inverter-based resources (IBRs) focus primarily on grid-following (GFL) technologies at present. Therefore, these may generally not be appropriate application in power systems to ensure acceptable operation with grid-forming (GFM) technologies. In some cases, the direct of prevailing standards for—or even inadvertently limit potential of—GFM resources. The Universal Interoperability Grid-Forming Inverters (UNIFI) Consortium is a U.S. Department Energy funded...
This article presents a tri-port current-source soft-switching medium-voltage string inverter (TMVSI) to reduce the Levelized cost of energy (LCOE) large-scale solar-plus-storage (SPS) farms. Throughout this work, topology, operating principle, circuit simulation, control, and hardware design TMVSI are introduced. In addition, three key challenges compromising performance addressed in article. First, new feed-forward compensation for model predictive control is proposed compensate sampling...
In this paper, an ultrafast active rectifier is presented for variable-frequency applications. Three-phase ac-dc converters (rectifiers) are extensively implemented in motor-drives, wind turbines, electric vehicles, and aircraft's power systems. some technologies, e.g., more aircraft drones, systems may employ generators higher efficiency reliability indices. The proposed equipped by a step-ahead predictive control scheme, instantaneous phase-locked loop (PLL), module of six SiC MOSFETs....
Magnetic components have become one of the primary barriers to high power density converters, especially current-source converters (CSCs). In CSCs, inductors/transformers a predominantly dc flux store energy, which can be offset by standard permanent magnets (PMs). However, eddy currents in PMs induce significant losses and thermal stress for medium-frequency applications. This article proposes using laminated while reducing currents, leading reductions size, cost, inductors/transformers....
Power electronic converters are the enabling technology and future of More Electric Aircraft (MEA). One major changes in MEA is that main ac-bus frequency varies over a wide range (360-800Hz). Thus, for applications power must operate under wild conditions. In this paper, three-phase unity factor (UPF) active rectifier with optimum space-vector predictive dc voltage control (OSVP) variable supply presented. The proposed controller takes into account supply's change by means an instantaneous...
In this article, a seamless dynamics controller for wild-frequency active rectifiers in more electric aircraft (MEA) is presented. The novelty of the proposed control scheme resides its ability to seamlessly regulate output dc-bus voltage and input reactive power presence rapid frequency changes. These smooth are achieved through multivariable direct model reference adaptive (MRAC) formulation, which allows gains adjust themselves operation MEA generation. validity performance effectiveness...
Grid-forming inverters are the key enablers for integration of inverter-based resources at scale. A critical component grid-forming control architecture is emulation virtual impedance. However, impedance implementation along with inner current loops can affect converter stability. To ensure harmonic stability under widely varying operating conditions, this paper analyzes passivity inverter and converter-side loop. Effective admittance derived from then used to analyze properties inverters....
Variable-frequency schemes have increased their presence in aerospace applications while maintaining popularity hybrid electric vehicles. In this article, the dynamic performance under parameter mismatch of a variable-frequency ac-dc converter is analyzed. A Lyapunov-based adaptive estimation algorithm developed, and included control scheme to address degradation that occurs from between hardware controller due ambient operating conditions. Because technique, proposed can effectively...
Energy access to off-grid communities has been historically limited by the availability and cost of bulk power system interconnection. Modern technologies with steep, sustained learning rates, e.g., solar batteries, are capable disrupting this trend making energy available equitably across population, especially if storage combined create a dispatchable resource. Nonetheless, cost-effective scalable solution that integrates solar, storage, output ac remains key roadblock toward distributed...
This paper presents a novel isolated bidirectional tri-port microconverter (TPMC) for hybrid solar plants that integrates panels with energy sources, such as batteries. The proposed TPMC achieves high-performance functionality minimal component count using the developed mode-sequence-based control scheme. It also features inherent ability to manage and recover stored in leakage reactance leading enhanced efficiency, reduced stress on switching devices. strategy realizes simpler low-cost...
Low inertia power generation units make islanded microgrids and nanogrids more vulnerable to voltage fluctuations. Smart loads are a possible solution suppress fluctuations in nanogrids. Since smart utilize inverters with short-time responses, their dynamics would have considerable effect on the stability of nanogrids, Therefore, play significant role for analysis these systems. This paper analyzes dynamic behaviors Furthermore, state-space model is developed loads. The studied using model,...
This paper proposes an off-line method to determine the electrical parameters of induction machine based on two instantaneous indicators (impedance and power). The uses start-up voltage current measurements. Also, proposed employs a space vector dynamic model referred fixed stator reference frame. allows representation in terms parameters. An error function is defined using obtained from measurements, versus corresponding derived machine. estimated are by minimizing this means constrained...
The efficiency estimation of electric motors has become a key subject due to industrial energy policies, environmental concerns, and the cost electricity. It is major interest test machine in-situ, as installation conditions local grid voltage unbalance deeply affect motor. To address this issue, paper presents methodology estimate three-phase induction in-situ. proposed method only requires direct start-up motor acquire stator current waveforms during acceleration process. was validated...
In this paper, an adaptive control scheme for active rectifiers in wild frequency applications is presented. The proposed controller addresses the performance degradation when parameters of model deviate from actual system a variable power system, e.g. More Electric Aircraft. particular, dynamically tracks input filter converter order to minimize prediction error one-step-ahead algorithm. Experimental results on SiC-based rectifier are provided assess effects parameter mismatch under...
The distribution grid of the future will have a variety generation resources. With help such distributed energy resources (DERs), should be able to fragment and coalesce form microgrids as needed for enhanced resiliency. In microgrids, distinction between different events faults topology change/load step can challenging. Especially single line grounds in an unbalanced microgrid, where zero sequence components are already present. proposed method analyses current waveform through...
Grid-forming (GFM) converters are gaining momentum as one of the keys to enabling large-scale integration distributed energy resources (DER) with grid. Among desired functionalities, GFM must demonstrate a stable fault-ride-through (FRT) behavior, i.e., during and after fault is cleared in system. As GFMs exhibit voltage source current needs be limited under conditions. In addition, control should ensure that load angle does not go into an unstable region. Also, once cleared, converter...
This two-part paper presents a novel multimode control-scheme for family of single-stage high-frequency-link bidirectional Universal Minimal Converters (UMC). Part-I developed multi-mode control strategy around the idea reducing converter to UMC cell, where deadbeat response was single switching cycle. It seen that desired objective charge transfer from sending-port receiving-port could be done with multiplicity modes, each widely different attributes. An optimization approach showed an...
This two-part paper presents a novel multimode control scheme for family of single-stage high-frequency-link bidirectional converters with DC or AC ports. These configurations represent universal-minimal-converters (UMC), which can all be reduced to generic unit cell over each switching cycle using the proposed scheme. universal and simpler integrates major parasitic while achieving lower device stresses than traditional schemes. A mode selection strategy is also utilized optimize...