Gefei Kou

Wide-Area-Measurement System Development at the Distribution Level: An FNET/GridEye Example

Summary form only given. Electric power grid wide-area monitoring system (WAMS) have been extended from the transmission to distribution level. As the first WAMS deployed at the distribution level, the frequency monitoring network FNET/GridEye uses GPS-time-synchronized monitors called frequency disturbance recorders (FDRs) to capture dynamic grid behaviors. In this paper, the latest developments of monitor design and the state-of-the-art data analytics applications of FNET/GridEye are introduced. Its innovations and uniqueness are also discussed. Thanks to its low cost, easy installation and multi-functionalities, FNET/GridEye works as a cost-effective situational awareness tool for power grid operators and pioneers the development of WAMS in electric power grids.

Impact of Governor Deadband on Frequency Response of the U.S. Eastern Interconnection

This paper documents the effort to perform dynamic model validation for the U.S. Eastern Interconnection (EI) by modeling the governor deadband. The Western Electricity Coordinating Council-modified 1981 IEEE type 1 turbine governor model (WSIEG1) was added to the EI model. A frequency response sensitivity study is conducted to look at the impacts of a few major factors. The significance of modeling governor dead band is evident. Simulated frequency responses are adjusted and validated against the measurements collected by the frequency monitoring network. Two actual events are replicated in a 16 000-bus EI dynamic model. This paper demonstrates the need for a comprehensive effort on governor dead band modeling by the industry.

Impact of High PV Penetration on the Inter-Area Oscillations in the U.S. Eastern Interconnection

This study explores the impact of high-photovoltaic (PV) penetration on the inter-area oscillation modes of large-scale power grids. A series of dynamic models with various PV penetration levels are developed based on a detailed model representing the U.S. Eastern Interconnection (EI). Transient simulations are performed to investigate the change of inter-area oscillation modes with PV penetration. The impact of PV control strategies and parameter settings on inter-area oscillations is studied. This paper finds that as PV increases, the damping of the dominant oscillation mode decreases monotonically. It is also observed that the mode shape varies with the PV control strategy and new oscillation modes may emerge under inappropriate parameter settings in PV plant controls.

Developing generic dynamic models for the 2030 Eastern Interconnection grid

The Eastern Interconnection Planning Collaborative (EIPC) has built three major power flow cases for the 2030 Eastern Interconnection (EI) based on various levels of energy/environmental policy conditions, technology advances, and load growth. Using the power flow cases, this paper documents the process of developing the generic 2030 dynamic models using typical dynamic parameters. The constructed model was validated indirectly using the synchronized phasor measurements by removing the wind generation temporarily.

Dynamic Model Validation with Governor Deadband on the Eastern Interconnection

This report documents the efforts to perform dynamic model validation on the Eastern Interconnection (EI) by modeling governor deadband. An on-peak EI dynamic model is modified to represent governor deadband characteristics. Simulation results are compared with synchrophasor measurements collected by the Frequency Monitoring Network (FNET/GridEye). The comparison shows that by modeling governor deadband the simulated frequency response can closely align with the actual system response.

Developing dynamic models for the 2030 Eastern Interconnection grid

The Eastern Interconnection Planning Collaborative (EIPC) has established three major power flow cases for the 2030 Eastern Interconnection (EI) grid based on various levels of energy and environmental policies, technology advances, and load growth. This paper documents the procedures of developing 2030 EI dynamic models using parameters from the Multiregional Modeling Working Group (MMWG) model and using the generic models. The constructed model is validated indirectly using the synchronized phasor measurement by displacing wind machines with conventional generators.

Non-Invasive Identification of Inertia Distribution Change in High Renewable Systems Using Distribution Level PMU

This letter proposed an approach to identify the change of inertia distribution in high renewable power systems. Using the footprints of electromechanical wave propagation at the distribution level, this approach provides a new and non-invasive way to aware the system inertia distribution for primary frequency response. Actual measurements and high renewable dynamic models validated effectiveness of the approach.

Rotor angle stability and inter-area oscillation damping studies on the U.S. Eastern Interconnection (EI) under high wind conditions

This paper studies the impact of wind generation on generator rotor angle and inter-area oscillation stability. A comparative simulation study is conducted based on a U.S. Eastern Interconnection (EI) planning model for year 2030. The wind penetration level is 17% of the total generation. Generator critical clearing time (CCT) and inter-area oscillation damping ratio are evaluated. It is observed that rotor angle stability is barely affected while inter-area oscillation damping shows discernible improvement due to wind generation. Possible explanations are then explored.

Design of a large-scale virtual power grid for research community

Due to security and liability concerns, the research community has limited access to realistic large-scale power grid models to test and validate new operation and control methodologies. It is also difficult for industry to evaluate the relative value of competing new tools without a common platform for comparison. This paper proposes to develop a large-scale virtual power grid model that retains basic features and represents future trends of major U.S. electric interconnections. The proposed model will include realistic power flow and dynamics information as well as a relevant geospatial distribution of assets. This model will be made widely available to the research community for various power system stability and control studies and can be used as a common platform for comparing the efficacies of various new technologies.

Primary Frequency Response Adequacy Study on the U.S. Eastern Interconnection Under High-Wind Penetration Conditions

This paper investigates the primary frequency response adequacy of the U.S. Eastern Interconnection with high-wind penetration in the year 2030. This paper starts with the creation of a realistic baseline dynamic model by validating against synchrophasor measurements. A dynamic simulation is performed to evaluate the impact of high-wind generation on a primary frequency response. Mitigation measures are then investigated.