Research Activity

EPIC has developed an extramural-funded research program that is “additive” to existing departmental activities. Through focused corporate engagement and government leverage from corporate funds, EPIC Research Verticals empower EPIC Assistant Directors of Research (ADoR) to complete research deliverables on an industrial client’s schedule. With the ability to use dedicated full-time staff that report to an ADoR and by recruiting faculty from UNC Charlotte and outside institutions, EPIC is able to successfully tackle cross-cutting, multidisciplinary, large research projects.

EPIC Research Verticals

  • Energy Infrastructure
  • Energy Systems Management
  • Environment & Construction
  • Power & Energy Conditioning
  • Precision Manufacturing
  • Research & Special Projects
  • Strategic Development & Faculty Liaison

See below for more details and examples of recent research activities.

Energy Infrastructure

Utilizing the resources of the EPIC High Bay Structures lab and associated specialty labs, large-structures research on transmission and distribution designs, materials characterization and development, and performance monitoring are performed.

Mechanical Load-Carrying Characteristics and Failure Mechanisms of Composite Insulators

New polymer materials being used to manufacture insulators require a thorough experimental evaluation before they can be used with confidence in the grid. For example, as insulator materials and geometries change, so do failure mechanisms, thereby effecting design requirements. Also, improved computational capabilities allow vendors to analyze their insulators in more detail and customize their products in terms of base material, weathersheds, and end fittings. These differences among vendors make it more difficult to establish a standard design protocol across the industry and may be leading to more (or less) conservative designs. Beginning almost five years ago and with continuing support from the Electric Power Research Institute (EPRI), faculty and staff at EPIC evaluate the physical load-carrying capabilities and failure mechanisms of various insulators. Using the HighBay Structures Lab at EPIC, both braced and unbraced insulators are configured, attached, and loaded at full scale just as they will be installed and loaded in the field. Deflections, stresses, strains, and failure data are collected during the test, simultaneously in three directions. This on-going research evaluates various insulators, conducts feasibility studies on new designs, identifies key parameters that alter performance regardless of the vendor, and recommends standard design requirements that reduce the risk of damages or failure, optimize the use of materials, and improve grid resiliency.

Energy Systems Management

The Energy Management group (EM) at EPIC primarily supports EPIC and its partners in developing and testing the technologies needed to modernize the power grid and better manage the flow of energy. This research unit focuses on all aspects of the power system, from generation all the way down to end-use applications. The group maintains state-of-the-art facilities with the computational infrastructure needed for advanced modeling applications and hardware-in-the-loop (HIL) testing.

A key facility maintained by the EM group is the Duke Energy Smart Grid Laboratory (DESGL). Managed by Dr. Behnaz Papari, the DESGL includes a real-time digital simulation test-bed that can perform real-time power-system analysis and functional testing for smart-grid devices. Using its power amplifiers, the lab can perform power hardware-in-the-loop (PHIL) testing at levels up to 100kW. The lab also includes many protective relays and is capable of real-time, closed-loop relay testing.

Researchers in the EM group have been leading many projects that leverage the capabilities of the DESGL. In collaboration with researchers in the Power and Energy Conditioning Group and members of The Charlotte Visualization Center in the College of Computing and Informatics, several faculty have been developing real-time power-system models for microgrids. The lab has also initiated proprietary contracts with companies developing new technologies for power generation and energy storage. The team has been developing hardware-in-the-loop tests designed to investigate how these devices function in a real power system.

The DESGL has also continued to play a major role in many Senior Design projects. Duke Energy and Schweitzer Engineering Laboratories (SEL) have been the primary sponsors, with many projects focused on protection, fault location, and meter and device placement. Several projects have also been supported by the Center for Advanced Power Engineering Research (CAPER). These activities have focused primarily on simulation and control algorithms for optimizing microgrids that combine photovoltaic generation with battery storage.

The EM group also includes projects focused on energy efficiency in end-use applications. Dr. Robert Cox maintains the Industry/University Cooperative Research Center for Sustainably Integrated Buildings and Sites (SIBS), which leverages support from both the National Science Foundation and private sector partners to focus on improving energy management in commercial buildings. Lead partners include Wells Fargo, Bank of America, Ingersoll Rand, and the City of Charlotte. A major focus for SIBS has been energy-management strategies for retail banking locations. SIBS researchers have also leveraged the computational capabilities of the DESGL to develop design tools intended to help our partners design, build, and operate zero-net-energy buildings.

The EM group has also been focused on expanding its technical service offerings. Initially, these activities included only hardware-in-the-loop testing, but they have now been expanded to include end-use energy auditing.

Environment & Construction

The Environment & Construction vertical provides solutions for problems related to the treatment of industrial wastewater and stabilization and reuse of waste produced during energy generation. In addition, this vertical is closely working with industry partners to solve the technological hurdles related to the construction of new power plants.

Power and Energy Conditioning

Power and Energy Conditioning (PEC) group at EPIC is committed to supporting EPIC and its partners in developing and evaluating solutions for safe, reliable, and affordable delivery of electrical energy to the end consumers. This research unit works on both transmission and distribution aspects of power delivery infrastructure and has been thematically focused on resilience along with two key enablers flexible grid-edge power conversion and open-source control solutions. Specifically, on the topic of resilience, our PEC team has been leading activities in two major programs: Cyber Vulnerability of Electrical Infrastructure and Protection & Control in Electrical Infrastructure and our personnel are actively engaged in developing the Flexible Energy Laboratory as a prime resource for EPIC and partners.

The Flexible Energy Laboratory offers a secure environment to conduct functional performance and pre-compliance testing of power and energy systems. This laboratory provides a grid simulator capability to test and evaluate equipment rated up to 1 MVA power at voltages up to 4160Vac and 1200Vdc. Test capabilities include pre-compliance testing for IEEE and UL standards such as IEEE 1547 and UL 1741 with common tests that this laboratory has been designed to perform being anti-islanding testing and low voltage and zero voltage ride through. Functional performance tests include efficiency and accelerated tests for reliability. The Flexible Energy Laboratory also includes high voltage (100kV) and high current (4000A) area for testing cables, transformers, and other high voltage equipment. Focusing on standards such as IEC 60840, IEC 620067, AEIC-CS-9, and ICEA-S108-720, this laboratory offers infrastructure to conduct water penetration tests, impulse type tests, corrosion tests, dielectric tests, tension/elongation tests, hot set and hot creep tests and HALT tests. The Flexible Energy Laboratory is also home to a grid modernization testbed, which includes real-time digital simulators such as Typhoon and Opal RT, multiple racks with protection and control equipment, and state of the art tools to perform hardware TPM based and PMU data-based cyber vulnerability assessments.

Principal projects at PEC included design, prototyping, and testing of a Si and SiC-based grid edge power converter and development of real-time digital simulation models of a distribution feeder with microgrid and customer-owned distributed energy resources for Duke Energy. In addition to these flagship projects, in support of the Affiliate Program at EPIC, our researchers also initiated hardware TPM based cybersecurity activity with support from Duke Energy and conducted a successful evaluation of a low voltage (600V-class) solid-state circuit breaker with support from Atom Power. The team also received a grant awarded by the UNC Coastal Studies Institute (CSI) to investigate aspects of protection and control in a multi-terminal HVDC system and a grant awarded by the Center for Advanced Power Engineering Research (CAPER) to study the effectivity of PMU data analysis for cyber event detection. The investigators associated with PEC also received a small RAPID project from the National Science Foundation to investigate the power ecosystem failure in Puerto Rico in the aftermath of Hurricane Maria, and a multi-year large grant from US Department of Energy to perform evaluation of Open-Field Message Bus (Open-FMB) based Fault Location, Isolation, and Supply Restoration (FLISR) in power distribution system.

Carbon-Ion Energy Storage Testing, Measurement and Characterization Capability

Carbon-Ion (C-Ion) is a capacitive energy storage technology using novel nano-carbon materials and advanced electrolytes. It is an economically competitive technically viable solution for utility grid energy storage. A flexible, multi-functional single and multi-cell (pack) test setup with repeated cycling capability and test data acquisition has been built at EPIC with the capability for constant current, voltage charging, and power discharging. EPIC offers expertise in analysis, modeling, and design of the Utility Scale Prototype Energy Storage Demonstrator.

Precision Manufacturing

The Precision Manufacturing research unit is committed to supporting EPIC efforts related to part production and measurement. These efforts cover multiple lengths scales from meters in overall dimensions to micrometers in measurement accuracy. The two primary resources to achieve this high-quality support are personnel and equipment. Personnel includes multiple faculty and graduate students from MEES. State-of-the-art manufacturing and metrology equipment are maintained in the department and associated laboratories, including the Siemens Large Manufacturing Solutions Laboratory (SLMSL), Center for Precision Metrology (CPM), and Center for Freeform Optics (CeFO).

Externally funded research includes a three-year, $1.8M grant from the University of North Carolina General Administration Research Opportunities Initiative to advance the art and science of metal-based additive manufacturing (AM). UNC Charlotte is partnering with NC State University and NC A&T University on this effort. A major deliverable of this project is to demonstrate how metal-based additive manufacturing can be used to save time and cost and enable new capabilities. Siemens Energy is also participating in this effort with a focus on the creation of geometrically complex copper components for generators. Siemens Corporate Technology has also joined and is studying in-process methods to detect internal flaws in metal AM parts.

Current projects encompass research in design, measurement, machining, and other areas.

Digital Assembly of Generator Stator Cores Into Frames

In the assembly process, 12 custom tapered shims are manufactured and welded into place to ensure proper alignment of the stator core within the frame. Previously, the core was placed on the support beam and the frame is brought over it and supported on jacks. An iterative process of manual adjustment and measurement was followed until the correct alignment was achieved. Next, the gaps to be filled were measured and custom shims were machined. The process required two to three shifts and is in the critical path for generator assembly. The UNC Charlotte team verified a new method where off-line measurements of the relevant surfaces on the stator core and frame were performed with a laser tracker. The digital models of the as-built components were then assembled in software and the shim dimensions computed. The shims were then pre-manufactured and directly installed with no iterative adjustments. This resulted in substantial time savings and removed effort from the critical path.

Strategic Development and Faculty Liaison

Responsible for managing two centers affiliated with EPIC, the Center for Advanced Power Engineering Research (CAPER) and the Center for Grid Engineering and Education (GridEd).

The Center for Advanced Power Engineering Research (CAPER) is a membership-driven consortium among three regional universities (UNC Charlotte, NCSU, and Clemson) and industry partners in the Southeast region of the US. The main mission of the center is to develop and demonstrate grid modernization technologies and enhance the educational experience for students in electric power engineering. With an aging infrastructure, rising demands for cleaner electricity and extreme weather conditions, the nation’s utilities are working to meet these operational and planning challenges while maintaining a resilient and reliable grid. As a collaborative effort, CAPER will develop research and demonstrate advanced technologies to meet the operational and expansion needs under uncertainties with an increased penetration of distributed renewable generation.

How State Regulators are Attributing Costs and Benefits to Distributed Generation

As Distributed Generation (DG) has become more common, state regulators have grappled with how to properly value the resource in relation to its impacts on the grid. Numerous state agencies have studied the issue of valuing DG to varying degrees in an attempt to determine fair, long-term solutions. To determine best practices for the southeast, the team will undertake an analysis of DG valuation studies conducted by state utility commissions and other agencies. This project will compare the overall DG values themselves, the value of various DG components where available, and methodologies used to determine DG value components.

Critical Infrastructure Resilience of the Distribution Grid

A grid resiliency improvement solution was studied. It features extensive use of distributed energy resources (DER) as well as the emerging concept of a microgrid operating within a wireless sensor network (WSN) for enhanced responsiveness and faster restoration of power to critical loads. The project has the potential to significantly reduce the outage time during high-impact, low-frequency weather events. The team has developed software that uses data analytics to identify the type and location of faults on the distribution system. The software will also identify the boundary of the service area that will experience an outage and the total number and location of customers who will experience an outage. The team also developed a software algorithm that optimizes a schedule for first responders for the fastest most effective restoration of distribution system during routine and major network outages due to severe weather events and terrorist attacks.

Identification, and Mitigation of Coordinated Attacks on Distributed Energy Management

The power grid of the future will contain millions of intelligent embedded sensors and control devices that will allow the system to operate in a distributed and decentralized manner. This project will develop a formal framework to characterize the attack space by verifying the feasibility of an attack, determining its consequences, identifying adversarial attributes, and determining how these are influenced by interdependencies between the cyber/computing and physical components. The proposed framework also determines the most cost-effective risk mitigation considering the security benefit.

Smart Fault Location Algorithms for Improved Distribution System Resilience

There is now an increased interest among electric utility companies to implement an advanced distribution management system (ADMS) software platform in their regular operational activities. ADMS provides smart grid functionalities, such as conservation voltage reduction (CVR), demand response (DR), fault location, isolation, and service restoration (FLISR) etc. The ADMS platform improves power quality, increases reliability and resiliency, and manages the integration of distributed energy resources (DER) effectively. This project proposed a fault location scheme as a part of the FLISR program based on the measurement from wireless sensors and smart meters deployed throughout the feeder to locate simultaneous faults. Sensors and smart meters use wireless sensor network (WSN) and advanced metering infrastructure (AMI), respectively. The fault location scheme also considers the bi-directional power flow complexities with the integration of PV based DERs at the edges of the grid. Initially, a modified depth-first search (MDFS) was utilized to reduce the search space to find the faulty zone(s) bounded by two sensor buses, and then, a voltage profile analysis is conducted in the specified zone(s) to find the actual faulty section(s). To demonstrate the robustness, the entire algorithm was tested on a utility-scale feeder with various loading, DER penetration, and fault resistance condition using Monte-Carlo (MC) method.

Planning an Affordable, Resilient, and Sustainable Grid in North Carolina

EPIC is currently embarking on an ambitious project to develop a roadmap to be used during the integrated resource planning process to support investments that build grid resiliency while maintaining affordable and reliable power. Reliability is commonly a component of utility planning and operation, yet resilience is an emerging emphasis in the aftermath of large weather-related events. Grid reliability studies focus on expected disruption events as well as evaluate the meantime between failures and system availability through well-known metrics such as SAIFI (System Average Interruption Frequency Index) and SAIDI (System Average Interruption Duration Index). On the contrary, resiliency studies emphasize the impact of low-probability, high- impact events such as hurricanes. Multiple groups, including the Department of Energy, the National Association of Regulatory Utility Commissioners (NARUC), and the National Academies, cited the need to develop metrics that can guide resiliency-based investments. The project team is conducting such a study in the context of North Carolina, emphasizing resiliency to ready the state for large-scale hurricanes. The results of the study would be broadly applicable to other states and regions.