Research Activities

BUDGET PERIOD 1: RESEARCH ACTIVITIES

Under Task 1: Model integrated T&D system with control (device level) and communication layer and incorporating DER

  1. The reduced model of 118 bus Transmission (T) system has been developed. The reduced model of 118 bus system is 19 bus transmission system.

  2. The reduced model of 8500 bus Distribution (D) system has been developed. The reduced model of 8500 bus system is 650 bus distribution system.

  3. A combined T&D model with 19-bus T-system and 650-bus D-system has been successfully developed.

  4. Power flow convergence error are with in 1% for combined T&D system when compared with independent T and D system power flow results .

  5. The average and EMT, DER models are developed using Powerfactory.

  6. The average solar inverter model developed in Powerfactory was tested for different operational scenarios.

  7. Developed a python-based OpenDSS – NS3 – ReDisPV controller interface incorporating the communication network with the physical power grid model.

Under Task 2: Design and develop algorithms for forming DER clusters

  1. Developed a dynamic T and D co-sim model with DER models operating in different modes.

  2. Load flow results validation of 650 bus distribution system.

  3. Developed a spectral clustering-based DER clustering approach including sensitivities.

  4. Testing the clustering approach with varying grid conditions on 123 bus and 650 bus distribution systems.

  5. Both static and dynamic clustering have been developed and tested on 123 bus and 650 bus distribution systems.

Under Task 3: Build a centralized version of distribution optimal power flow-DOPF

  1. Developed a simple 33-node single-phase multi-period NLP DOPF to highlight advantages over sequential single period NLP DOPF model.

  2. Multi-period 3-phase DOPF with continuous variables (SOCP) for three-phase 650-node distribution system with 50 PV inverters has been developed.

  3. Multi-period 3-phase DOPF with continuous variables (SOCP) for 3-phase 650-node distribution system with 50 PV inverters and 5 inline regulators has been developed.

  4. Multi-period Three-phase DOPF with discrete variables (SOCP) for three-phase 123-node distribution system is developed.

  5. A three-phase distribution grid optimal power flow (DOPF) model is developed with LTC as integer control variables using mixed-integer second-order cone program (MISOCP).

Under Task 4: Develop dynamic control architecture, controller design adaptation, and lead controller selection

  1. Designed components/modules of dynamic resilient control architecture (DRCA) that implements a moving target defense algorithm to minimize the vulnerability surface of a cluster of DERs against both cyber and physical threats .

  2. Developed two distinct computational platforms: Design and Optimization platform (DOP) and Verification and Validation platform (VVP), to analyze and optimize performance of DRCA.

  3. A test setup comprising of 4-10 DERs has been successfully developed in MATLAB/Simulink and evaluated under diverse scenarios.

  4. DER models include completed modules of DRC architecture. Communication channels has also been simulated between: i) area control center (ACC) and lead DER controller; ii) DERs within cluster.

Under Task 5: Evaluate conventional protection schemes in the presence of renewables and propose/evaluate a suitable method

  1. Average models of the detailed switching models of inverters developed during the first two quarters were created and tested successfully.

  2. A fully reconfigurable 123-bus feeder model was created in PSCAD, with 7 protection/reconfiguration zones and 15 IBRs (average models).

  3. Several cases were run to show the isolation and reconfiguration of zone(s) can be stably performed.

  4. This lays the foundation for implementing the protection scheme that is being developed. Reconfiguration and protection strategies will be topology-agnostic and scale-able.

  5. Conceived and implemented the primary protection scheme on a fully reconfigurable 123-bus feeder model created in PSCAD in Q3.

  6. Successfully tested the primary protection scheme based on the metric provided.

  7. Successfully tested the backup protection scheme when the primary protection fails to clear the fault for any reason.

  8. Clearance and reconnection for temporary faults also addressed and tested.

Under Task 6: Creating a communication network model that provides robust communication structures for enabling the communications in the distributed PV systems enabled the smart grid and integrating the model with Task 1

  1. The communication modeling architecture has been developed which focuses on building a scalable, information-centric networking (ICN) based network infrastructure, to meet the latency and bandwidth requirements of communications.

  2. To validate communication modeling architecture and implementation we performed several simulation tests on three test network 19 bus, 37 bus and the 650-node power network.

  3. An integrated power grid and communication simulator is also designed and developed.

Under Task 7: Transmission and Distribution network model development/conversion and validation using OPAL-RT simulator.

  1. The IEEE 118 bus transmission network and 650 nodes distribution model were converted to ePHASORSIM. Models validated with the respective offline simulations.

  2. Models integrated to form a T&D integrated model for real-time simulation and characteristic validation performed.

  3. Developed EMT domain IEEE 123 nodes distribution feeder in eMEGASIM. Configured the model to run real-time in two CPU cores.

  4. A preliminary DER model developed in SPS.

BUDGET PERIOD 2: RESEARCH ACTIVITIES

Under Task 8: Identify and model physical vulnerabilities based on the power grid model.

  1. Encapsulates (T&D) system integrated model in one platform: Digsilent Powerfactory.

  2. Initial development of vulnerability assessment capability for assessing distribution system assets.

  3. Development of voltage deviation metric to quantify the impact of DER operation on system voltage.

  4. Initial development of vulnerability ranking of DERs based on their impact on system operation.

  5. α-version of development of vulnerability assessment capability for assessing distribution system assets.

  6. Development of various metrics to quantify impact of DER operation on distribution system operation.

  7. Development of vulnerability ranking of DERs using various metrics based on their impact on system operation.

  8. Vulnerability analysis of DER clusters and feedback to cluster formation.

Under Task 9: Develop area controller for dynamically selected clusters and evaluating the architecture.

  1. ADMM algorithm has been designed and verified which can optimally manage each area power flow and provide a consensus framework.

  2. MPC algorithm has been designed .

  3. The model predictive control architecture is integrated with ADMM framework and will provide control signal to the lead cluster device.

Under Task 10: Large-scale distribution optimal power flow (DOPF) and integration with other modules.

  1. A three-phase distribution grid optimal power flow (DOPF) model is developed with PV as controllable resource using a second-order cone program (SOCP) model.

  2. The performance and computational complexity of SOCP based DOPF model is tested using a 2522-node three-phase distribution system with 50 PVs.

  3. A three-phase distribution grid optimal power flow (DOPF) model is developed with PV as controllable resource using a Linear Programming (LP) model and performance was evaluated using 2522-node distribution network distribution network with 50 PVs.

  4. A distributed version of DOPF model is developed and initial testing and validations are carried out using the IEEE 123-node test feeder.

Under Task 11: Development of risk/health-based resiliency modeling/monitoring framework.

  1. Initial formulation of risk informed cluster evaluation (RICE) framework.

  2. RICE quantifies risk indices utilized by DRCA and command center to proactively resist and mitigate physical and/or cyber threats to DERs and clusters and inform cluster configuration to form low risk clusters.

  3. Development of Monte Carlo simulation infrastructure to simulate various threat scenarios and collect data for training of RICE module.

Under Task 12: Integrate (with Task 9, Task 13 and Task 14) the protection methodology with the controller.

  1. As a first step in the integration task, the simplified (average) inverter models developed in the PSCAD platform are migrated onto the MATLAB platform.

  2. IEEE 123-node test feeder, averaged inverter models, primary protection scheme, load shedding scheme, and reconnection of the island using the check-synchronizing feature are ported successfully from PSCAD to MATLAB/Simulink Platform.

  3. Except for Load Shedding Scheme, these models are also ported to Opal-RT platform.

  4. Alongside, at Clemson facilities, primary protection is co-simulated with the 61850-compliant communication on the RTDS platform with HIL – Preparation for Year 3.

Under Task 13: Design threat detection model and latency sensitive communication considering vulnerability assessments from Task 8 and risk threats from Task 11.

  1. The communication modeling architecture has been developed which focuses on building a scalable, information-centric networking (ICN) based network infrastructure, to meet the latency and bandwidth requirements of communications.

  2. To validate our design and implementation we performed several simulation tests on four test network 19, 37, 123, and 650-bus power network.

  3. An integrated power grid and communication simulator is also designed and developed.

  4. Implemented DDoS attacks and studied the impact of NDN in general on it.

  5. To validate co-simulation we have performed co-simulation with the 650-bus power network.

  6. We notice the network characteristics changes when run in combination with ReDisPV.

Under Task 14: T&D network large-scale model development/conversion, validation and interfacing of communication and other modules with OPAL-RT simulator.

  1. 2500 nodes distribution model was converted, validated, and integrated with the IEEE 118 bus model.

  2. The EMT model of IEEE 123 nodes distribution feeder updated with circuit breakers and optimized to run in two CPU cores of OP4510 within 50µs time-step.

  3. The EMT model was validated by comparing results from real-time simulation and IEEE data.

  4. T&D integration method was improved and was used in integrating IEEE118 and 2500 node distribution feeder.

  5. Framework for integrating EMT domain inverter models in ePHASORSIM grid model was completed. Grid connected operation of inverters was validated.

  6. Fault detection and synchronization check modules were validated real-time in small circuit and were integrated in 7 zones of IEEE 123 model

  7. •Communication architecture between OPAL-RT and NS3 has been finalized.