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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Optimal Placement of PV Smart Inverters With Volt-VAr Control in Electric Distribution Systems
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An Adaptive Virtual Oscillator Control Structure for Grid-Forming Inverters
The electrical grid is facing unprecedented challenges due to the increasing penetration of inverter-based resources. Grid forming inverters (GFMIs) are a promising technology to address these challenges. Recently, the virtual oscillator based GFMI control is attracting more attention due to its superior performance over other control strategies. In this article, an adaptive control strategy is proposed to provide flexible operation and transition between grid-connected and islanded modes. The controller adapts the virtual oscillator's parameter values depending on the operation mode. It also provides a feedback signal using a measured frequency to account for any steady-state errors and to allow a seamless transition from grid-connected to islanded mode. Finally, to show the feasibility of the proposed controller, this article discusses the simulation results from the implementation of the controller on a single inverter system and on a group of inverters on a large practical utility feeder, the IEEE 13 node feeder, using the DIgSILENT simulation environment.
Blockchain Enabled Named Data Networking for Secure Vehicle-to-Everything Communications
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Sharding-Enabled Blockchain for Software-Defined Internet of Unmanned Vehicles in the Battlefield
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UAV-Aided RF Mapping for Sensing and Connectivity in Wireless Networks
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PT Symmetry-Enabled Physically Unclonable Functions for Anti-Counterfeiting RF Tags
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NeuSB: A Scalable Interconnect Architecture for Spiking Neuromorphic Hardware
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Cross Modality Bias in Visual Question Answering: A Causal View With Possible Worlds VQA
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Reinforcement Learning for Dynamic Dimensioning of Cloud Caches: A Restless Bandit Approach
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Module-OT: A Hardware Security Module for Operational Technology
Increased penetration levels of renewable energy and other types of distributed energy resources (DERs) on the modern electric grid-combined with technological advancements for electric system monitoring and control-introduce new cyberattack vectors and increase the cyberattack surface of energy systems. According to the IEEE Std. 1547-2018, DERs must use Modbus, Distributed Network Protocol 3 (DNP3), or Smart Energy Profile 2.0 (SEP2) as their communication protocol. Previous research identified several vulnerabilities and security breaches in each one of these communication protocols; despite this, existing standards for DERs do not recommend cybersecurity measures. In order to reduce vulnerabilities in power distribution systems, this paper presents a novel open-source hardware security module that improves both information and operational security to better protect data and communications on the distribution grid. The security hardware is called “module for operational technology,” or simply Module-OT, and it has been validated and tested in an emulated distribution system application. Module-OT is integrated within a communication system in the transport layer of the Open Systems Interconnection (OSI) model. It improves system security through encryption, authentication, authorization, certificate management, and user access control. The main advancement of Module-OT is the addition of hardware cryptographic acceleration that improves the overall communication performance in terms of end-to-end latency.
Online EV Scheduling Algorithms for Adaptive Charging Networks with Global Peak Constraints
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Efficient Data Collection in IoT Networks Using Trajectory Encoded With Geometric Shapes
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