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Hempel, Michael

Publications and source records attributed to Hempel, Michael.

5 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Time and Frequency Analysis of Load Profile Data

Technology advancements and integration of modern advanced metering systems can monitor, forecast, inform, control, and operate the building's mechanical, electrical, and plumbing (MEP) systems. They offer a higher level of information, which can contribute to making smart buildings more energy efficient and to making them closer to becoming grid-interactive energy efficient buildings (GEB). This paper builds on the ongoing research on variability analysis of a case study building with a 1-minute load profile and examines the Discrete Wavelet Transform (DWT) process in the frequency domain to quantify the signal's energy in each bandwidth, with respect to each end-use category. Moreover, the amount of variability in the total variability is not similar among the end-use categories. This information is needed to understand the behavior of the variability in the frequency domain for future applications, such as generating synthetic load profiles with a similar frequency spectrum as the measured signal.

decomposition↗
DOE OSTI2024

Toward Wireless Smart Grid Communications: An Evaluation of Protocol Latencies in an Open-Source 5G Testbed

Fifth-generation networks promise wide availability of wireless communication with inherent security features. The 5G standards also outline access for different applications requiring low latency, machine-to-machine communication, or mobile broadband. These networks can be advantageous to numerous applications that require widespread and diverse communications. One such application is found in smart grids. Smart grid networks, and Operational Technology (OT) networks in general, utilize a variety of communication protocols for low-latency control, data monitoring, and reporting at every level. Transitioning these network communications from wired Wide Area Networks (WANs) to wireless communication through 5G can provide additional benefits to their security and network configurability. However, introducing these wireless capabilities may also result in a degradation of network latency. In this paper, we propose utilizing 5G for smart grid communications, and we evaluate the latency impacts of encapsulating GOOSE, Modbus, and DNP3 for transmission over a 5G network. The OpenAirInterface open-source library is utilized to deploy an in-lab 5G Core Network and gNB for testing with off-the-shelf User Equipment (UE). This creates an effective 5G test platform for experimenting with different OT protocols such as GOOSE. The results are validated by measuring two different Intelligent Electronic Devices’ contact closure times for each network configuration. These tests are also conducted for varying packet sizes in order to isolate different sources of network latency. Our study outlines the latency impact of communication over 5G for time-critical and non-critical applications regarding their transition toward private 5G-based OT network implementations. The conducted experiments illustrate that in the case of GOOSE packets, simple encapsulation may exceed the protocol’s time-critical nature, and, therefore, additional measures must be taken to ensure a viable transition of GOOSE to 5G services. However, non-critical applications are shown to be viable for migration to 5G.

42 ENGINEERING↗
DOE OSTI2023

CYVET: A Cyber-Physical Assurance Framework Based on a Semi-Supervised Vetting Approach

The project is designed to directly address the needs described in the Topic Area 4 (“Cybersecurity Verification and Validation”) of the CEDS’19 Research Call. The proposed CYVET system directly addresses the need to elevate the current industry capabilities to verify and validate OT cybersecurity and associated control system infrastructure. Currently, there is a significant gap in the energy sector’s capability in that regard during infrastructure improvement, equipment procurement, and compliance certification. CYVET provides that needed capability. CYVET is device and architecture agnostic and thus broadly applicable across the energy sector. The goal of this project is to develop and deliver a cybersecurity verification and validation framework testing capability to verify and validate OT equipment, software, and the underlying control system architecture. The primary project objectives are (i) Verification: the synthesis and reconciliation of standards and vendor supplied features, (ii) Validation: the generation, execution, and presentation of testing scripts of verified security features, and (3) Demonstration: apply the developed technology capabilities for verification and validation at a relevant end-user facility in the energy sector.

Lopez Jr, Juan↗