Publications

• Authors: Kevin Chen (EPG), Lin Zhang (EPG)

Collect three phase measurements from substation equipment–Process data from PMUs, DFRs and Instrument Transformers to derive synchrophasor equivalents and run a three phase Substation Linear State Estimator (SLSE) in real-time–Monitor and characterize equipment data signatures–Detect signature anomalies–Alert end-users and provide equipment signatures for detailed forensic analysis

• Authors: Lin Zhang (EPG), Heng Chen (EPG), Kenneth E Martin (EPG), Anthony Faris, Megan Vutsinas, Tim Bradberry, Evan Phillips, Backer Abu-Jaradeh, Josh Bui

The US power industry has been pushing forward the adoption of synchrophasor technology for wide-area monitoring and situational awareness. Many applications have been developed to take advantage of the GPS time-stamped synchrophasor data. Linear State Estimator (LSE) is one of the recent developments in the synchrophasor industry that has been gradually accepted and adopted by several US utilities under pilot projects. This paper is aimed to provide the insights of successful deployments at the utility level, and to ...

• Authors: Lin Zhang (EPG), Heng Chen (EPG), Ken Martin (EPG), Anthony Faris

Phasor Measurement Units (PMUs) measure voltage and current phasors at the same time and relative to the same angle reference, so that it is feasible to use a Linear State Estimator (LSE) to provide a full system solution from these measurements. This paper explores the practical issues of LSE implementation using a phasor measurement system in the Western Electricity Coordinating Council (WECC) system. This project started with the Virginia Tech LSE algorithm and enhanced it to handle some special issues like series ...

• Authors: Heng Chen (EPG), Lin Zhang (EPG), Jianzhong Mo (EPG), Kenneth E. Martin (EPG)

State estimation is a critical functionality of energy management system (EMS) to provide power system states in real-time operations. However, problems such as failure to converge, prone to failure during contingencies, and biased estimates while system is under stressed condition occur so that state estimation results may not be reliable. The unreliable results further impact downstream network and market applications, such as contingency analysis, voltage stability analysis, transient stability analysis, system alarming, and unit ...

• Authors: Neeraj Nayak (EPG), Heng Chen (EPG), Wayne Schmus (EPG), Ryan Quint

Models are used widely in power system planning and operations studies, and play an important role in predicting the grid's response and preparing for contingencies. The North American Electric Reliability Corporation (NERC) has adopted standards for generator model validation requiring periodic validation of generator, exciter, governor, and stabilizer models. Using synchrophasor data provides a unique opportunity for generator owners to verify their dynamic models while the units are on-line, avoiding time-consuming and ...

• Authors: Lin Zhang (EPG), Anjan Bose, Anil Jampala, Vahid Madani, Jay Giri

As more phasor measurement units (PMUs) are installed, portions of the power grid become observable with just phasor measurements, making feasible the estimation of the state of these observable portions at much faster rates than the traditional state estimator. Although such a linear state estimator (LSE) was proposed over a decade ago, the first field implementation was completed at Dominion Virginia Power in 2013. Although this LSE is a stand-alone function not integrated to their energy management system

• Authors: K.D. Jones, E. Cano, H. Chen (EPG), F. Robinson, K. Thomas, R. Gardner

Of the many electric power grid characteristics that contribute to its strength and effectiveness, there are two attributes that truly illustrate the nature of the grid, its fibrousness and its scale. Continental interconnectivity allows for fast, affordable, and reliable energy delivery but comes at the cost of complexity. In this way, the properties of the grid that embody its magnitude also contribute to the challenge of monitoring, operation, and control.

• Authors: J. Ballance (EPG), B. Bhargava (EPG), H. Chen (EPG), P. Palayam (EPG), J. Hiebert

• Authors: H. Chen (EPG), J. Mo (EPG), U. Kothapa (EPG), B. Bhargava (EPG), J. Dyer (EPG)

SynchroPhasor measurement provides high resolution and time-synchronized data, which exposes the complex dynamics of the power systems across wide areas. Taking advantage of this technology, the Real-Time Dynamics Monitoring System (RTDMS®) Platform for on-line wide area dynamics monitoring has been developed by Electric Power Group. The platform utilizes an open and modular architecture and offers a suite of applications for real-time reliability monitoring, analysis and alarming. This paper provides ...

• Authors: H. Chen (EPG), K. Martin (EPG), B. Bhargava (EPG), V. Budhraja (EPG), J. Ballance (EPG)

Synchrophasor measurements provide highresolution, time-synchronized data, which exposes the complex dynamics of the power systems across wide areas. This technology enables collection of sub-second data from any part of the system the capability of real time monitoring of an entire interconnection. Taking advantage of this technology, an on-line islanding detection application has been developed in the RealTime Dynamics Monitoring System Platform. The islanding detection application utilizes frequency signals ...

• Authors: Lin Zhang (EPG)

With the advent of phasor measurement units (PMUs), the synchro-phasor data related applications at control centers have been researched in recent decades. Time- stamped phasor data can benefit the applications in modern power system, such as state estimation, voltage stability, oscillation monitoring, transient stability and so forth. As one of the key applications in Energy Management System (EMS), state estimation utilizing synchro- phasor data is the major objective of this dissertation.

• Authors: J. Dyer (EPG), J. Balance (EPG), R. Barreno, H. Chen (EPG), J. Mo (EPG), I. Singh (EPG)

• Authors: D. K. Molzahn, B. C. Lesieutre, H. Chen (EPG)

Existing literature claims that an algorithm based on continuation is capable of finding all solutions to the power flow equations for all power systems. This claim is demonstrated to be incorrect through the use of a five-bus system counterexample. Existing literature also claims that a similar algorithm is capable of finding all Type-1 solutions (ie, solutions where the power flow Jacobian has a single eigenvalue with positive real part) to the power flow equations for all systems. This claim is also shown to be incorrect using the ..

• Authors: Heng Chen (EPG), Bharat Bhargava (EPG), Farrokh Habibi-Ashrafi, Joshua S. Park, Juan Castaneda

Southern California Edison (SCE) is deploying advanced smart grid technologies in an integrated system as part of its Smart Grid Strategy and Roadmap. An integrated lab environment combined with Real Time Digital Simulator (RTDS) for simulation and Electric Power Group's (EPG) synchrophasor technology applications for data synchronization, visualization and analysis has been set up at SCE. This lab is being utilized to build simulation cases and models to test equipment, interoperability, control schemes, ...