arXiv subjects

Tuyen Vu

Publications and source records attributed to Tuyen Vu.

28 records · Page 2Linked to original sources

arXiv2022

Integrated Multiport Bidirectional DC-DC Converter for HEV/FCV Applications

This paper proposes a novel integrated multiport bidirectional dc-dc converter to interface the battery, the ultra-capacitor, the fuel cell, or other energy sources with the dc-link capacitor of the hybrid energy systems such as the hybrid electric vehicle (HEV) and fuel cell vehicle (FCV) applications. The proposed converter can be applied to the distributed generation systems which include local energy sources, storage, and loads. It can perform both buck and boost functions with fewer switches. In addition, it is extendable when more inputs and/or outputs are required. The operating principle and control strategy of the proposed converter will be analyzed in detail. For verification, simulation, and experimental results of the four utilized operating modes of an HEV/FCV are provided.

eess.SY↗

arXiv2022

Grid-Forming Inverter-based Wind Turbine Generators: Comprehensive Review, Comparative Analysis, and Recommendations

High penetration of wind power with conventional grid following controls for inverter-based wind turbine generators (WTGs) weakens the power grid, challenging the power system stability. Grid-forming (GFM) controls are emerging technologies that can address such stability issues. Numerous methodologies of GFM inverters have been developed in the literature; however, their applications for WTGs have not been thoroughly explored. As WTGs need to incorporate multiple control functions to operate reliably in different operational regions, the GFM control should be appropriately developed for the WTGs. This paper presents a review of GFM controls for WTGs, which covers the latest developments in GFM controls and includes multi-loop and single-loop GFM, virtual synchronous machine-based GFM, and virtual inertia control-based GFM. A comparison study for these GFM-based WTGs regarding normal and abnormal operating conditions together with black-start capability is then performed. The control parameters of these GFM types are properly designed and optimized to enable a fair comparison. In addition, the challenges of applying these GFM controls to wind turbines are discussed, which include the impact of DC-link voltage control strategy and the current saturation algorithm on the GFM control performance, black-start capability, and autonomous operation capability. Finally, recommendations and future developments of GFM-based wind turbines to increase the power system reliability are presented.

eess.SY↗

arXiv2022

Scalable Cyber-Physical Testbed for Cybersecurity Evaluation of Synchrophasors in Power Systems

This paper presents a real-time cyber-physical (CPS) testbed for power systems with different real attack scenarios on the synchrophasors-phasor measurement units (PMU). The testbed focuses on real-time cyber-security emulation with components including a digital real-time simulator, virtual machines (VM), a communication network emulator, and a package manipulation tool. The script-based VM deployment and the software-defined network emulation facilitate a highly-scalable cyber-physical testbed, which enables emulations of a real power system under different attack scenarios such as Address Resolution Protocol (ARP) poisoning attack, Man In The Middle (MITM) attack, False Data Injection Attack (FDIA), and Eavesdropping Attack. The common synchrophasor, IEEE C37.118.2 named pySynphasor has been implemented and analyzed for its security vulnerabilities. The paper also presented an interactive framework for injecting false data into a realistic system utilizing the pySynphasor module. The framework can dissect and reconstruct the C37.118.2 packets, which expands the potential of testing and developing PMU-based systems and their security in detail and benefits the power industry and academia. A case for the demonstration of the FDIA attack on the linear state estimation together with the bad-data detection procedure are presented as an example of the testbed capability.

cs.CR↗

arXiv2022

Real-time Transient Simulation and Studies of Offshore Wind Turbines

This paper presents developed real-time simulation models for offshore wind turbine generators in compliance with industry standards. The critical control functions such as negative sequence injection, sequence current limit, voltage ride through, and power curtailments are designed to meet the industry requirements for future electromagnetic transient (EMT) testing and controls of offshore wind farms. Average-value and switching detailed models are developed in the Opal-RT real-time simulator. Real-time capabilities of these models are compared to show the effectiveness of the average-value model in terms of accuracy and computation efficiency. Studies of balanced and unbalanced faults illustrate the ability of the proposed turbine models to inject active and reactive currents during fault events. The models are validated against the second-generation generic wind turbine model proposed by Western Electricity Coordinating Council (WECC). Validation results reveal that the proposed models are aligned with the WECC generic model. In addition, the models provide an extended capability in mitigating the active power oscillation during unbalanced fault conditions.

eess.SY↗

arXiv2021

Advanced Load Shedding for Integrated Power and Energy Systems

This paper introduces an advanced load shedding algorithm to improve the operability performance of a medium voltage direct current (MVDC) integrated shipboard power and energy system. Outcomes are compared to a baseline algorithm while considering power generation contingency scenarios. The case study is conducted with a real-time, embedded algorithm implementation using a control hardware-in-the-loop (CHIL) setup.

eess.SY↗

arXiv2021

Energy Management System for Resilience-Oriented Operation of Ship Power Systems

This paper proposes an original energy management methodology for enhancing the resilience of ship power systems considering multiple types of energy storage systems, including battery energy storage systems (BESS) and supercapacitor energy storage systems (SCESS). The primary function of the proposed EMS is to maximize the load operability while taking ramp-rate characteristics of energy storage systems (ESS) and generators into account innovatively. Balancing state-of-charge (SoC) of BESS and prioritizing the SoC level of SCESS are two additional objectives of the proposed EMS to manage energy storage systems. The receding horizon optimization (RHO) technique is proposed to reduce the computational burden, making the proposed method feasible for real-time applications. An all-electric MVDC ship power system is used to evaluate the performance of the proposed methodology. Simulation studies and results demonstrate the effectiveness of the proposed method in managing the ESS to ensure the system resilience under generation power shortage. In addition, the proposed RHO technique significantly reduces the computation burden seen in the FHO technique while maintaining an acceptable resilience performance.

eess.SY↗

arXiv2020

Modeling Communication Networks in a Real-Time Simulation Environment for Evaluating Controls of Shipboard Power Systems

Interest by the U.S. Navy in the development and deployment of advanced controls in future shipboard platforms has motivated the development of the Controls Evaluation Framework (CEF) for use in investigating dynamics present in complex automated systems. This paper reports on the implementation and investigation of a communication network component within the CEF. This implementation is designed to augment the CEF's available feature set, permitting the exploration of various communication conditions on advanced control performance. Results obtained from controller hardware-in-the-loop testing are presented and analyzed to demonstrate performance characteristics pertaining to the implemented module.

eess.SP↗

arXiv2019

Cyber-Physical Microgrids: Toward Future Resilient Communities

Research in monitoring and control of microgrids has been ongoing for the last two decades to protect and enhance communities' socio-economic performance. However, of increasing concern are the possible cyber-physical threats that could disrupt the provision of macrogrids' energy services to critical infrastructure and consequently impact the resilience and sustainability of communities. As cyber-physical systems, microgrids are not immune to these threats. Advanced monitoring and control are critical for real-time operations of microgrids and, therefore, directly influence communities' resilience. Research trends in monitoring have recently shifted from normal situational awareness in forecasting, state estimation, and prediction to anomalies' analysis and cyber-physical attacks' detection to support resilient control systems. In addition, confounding the interpretation of research findings is the lack of a widely accepted definition, analytical methods, and metrics to consistently describe the resilience of power grids, especially for microgrids. This paper provides an overview of current research in microgrid resilience and presents an outlook for future trends.

math.OC↗

arXiv2019

Distributed Optimal Dynamic State Estimation for Cyber Intrusion Detection in Networked DC Microgrids

In this paper, we present a novel distributed state estimation approach in networked DC microgrids to detect the false data injection in the microgrid control network. Each microgrid monitored by a distributed state estimator will detect if there is manipulated data received from their neighboring microgrids for control purposes. A dynamic model supporting the dynamic state estimation will be constructed for the networked microgrids. The optimal distributed state estimation, which is robust to load disturbances but sensitive to false data injected from neighboring microgrids will be presented. To demonstrate the effectiveness of the proposed approach, we simulate a 12kV three-bus networked DC microgrids in MATLAB/Simulink. Residual information corresponding to the false data injected from neighbors validates the efficacy of the proposed approach in detecting compromised agents of neighboring microgrids.

math.OC↗

arXiv2019

Plug-n-Play Alternating Projection Algorithm for Large-scale Security Constraint Optimal Power Flow

In this paper, we present an optimization algorithm based on an alternating projection method to solve the large-scale security constraint optimal power flow (SCOPF) problem in power systems. The SCOPF is first partitioned into sub-problems, which share common power components. The proposed algorithm is fundamentally a distributed computing algorithm, which optimizes power flow in each electrical bus. The output of the local optimization problem will be exchanged among neighboring buses for the overall solution for the whole power system. We performed the algorithm against a modified 14-bus power system and demonstrated that the method is competitive with the commercial products regarding the CPU computation time.

math.OC↗