University of Tennessee Research Foundation

Ut-battelle, Inc.

Lingwei Zhan

Yilu Liu

Wenxuan Yao

Jiecheng Zhao

He Yin

Peter L Fuhr

Thomas J King

Marissa E Morales-Rodriguez

Yong Liu

Bailu Xiao

Wei Gao

Haoyang Lu

Tom King

Daniel J King

Fuhua Li

Andrew N Herron

Thomas J King, Jr

A system determines the frequency of grid signals corresponding to an electrical grid in real time. The system includes a transient detector that monitors a grid signal from a voltage meter or a current meter connected to the electrical grid. The system produces, in real time and at a sampling rate, a deviation signal indicative of a periodicity of the monitored grid signal. The system determines, over one or more cycles of the monitored grid signal, a measurement signal corresponding to the deviation signal. The system determines a frequency signal that corresponds a frequency estimation of the monitored signal by applying a frequency estimation when values of the measurement signal are less than a deviation threshold and maintaining the frequency signal at a constant value when values of the measured signal equal or exceeds the deviation threshold.

Fault-tolerant grid frequency measurement algorithm during transients

A pulsar based timing synchronization method and system are disclosed. In one example, a method includes receiving, by a pulsar signal receiver device, a pulse signal emitted from one or more celestial objects and processing, by the pulsar signal receiver device, the pulse signal to discipline a local clock to determine an accurate time output. The method also includes generating, by the pulsar signal receiver device, a timing synchronization signal based on the determined accurate time output. The method further includes providing, by the pulsar signal receiver device, the timing synchronization signal to at least one of a local power system device and a timing distribution network server.

Pulsar based timing synchronization method and system

Embodiments of the present invention may provide a device for monitoring electric power at the distribution level. The device may include an analog-to-digital converter (ADC) to convert an input signal into digital samples at time intervals, a receiver to generate a pulse-per-second (PPS) signal, an oscillator to generate an oscillator signal, and a data processor coupled to the ADC, the receiver, and the oscillator. The data processor may include a counter to measure an oscillator frequency of the oscillator signal at each pulse of the PPS signal, an adjuster to adjust a timer period register value, and a timer to adjust the time intervals based on the adjusted timer period register value. Based on the digital samples, the data processor may generate a plurality of metrics, which may include one or more measurements of frequency, magnitude, phase, harmonic level, signal-to-noise ratio, sag, and swell of the input signal.

Universal grid analyzer

A synchrophasor measurement method for a device configured to take synchronized measurements in a power system is provided. The synchrophasor measurement method includes receiving global positioning system (GPS)-synchronized samples of a signal sensed by the device from the power system; determining a level of distortion of the signal; selecting, based on the level of distortion, a computation method, the computation method being one of an improved zero-crossing (IZC) method and an enhanced phase-lock-loop (EPLL) method; performing the selected computation method to determine at least one parameter of the signal at a reporting frequency, which is at least twice a line frequency of the power system; and outputting, at the reporting frequency, the at least one parameter to an operator of the power system to allow the operator to perform at least one of a monitoring and a controlling of at least one element of the power system.

Synchrophasor measurement method for power systems

A system may include an electric field sensor, an analog to digital converter, and an estimator. The electric field sensor may measure electric fields of electric power grid. The analog to digital converter may generate digital output based upon measurements from the electric field sensor. The estimator may estimate phasor data of the electric power grid based upon the digital output.

Mobile electric field sensor based phasor measurement unit for monitoring an electric power grid

Growing community of inventors

Knoxville, TN, United States of America

Lingwei Zhan