Universal grid analyzer

Patent metadata

Field	Value
Publication number	US-10598704-B2
Application number	US-201514802307-A
Country	US
Kind code	B2
Filing date	Jul 17, 2015
Priority date	Jul 17, 2015
Publication date	Mar 24, 2020
Grant date	Mar 24, 2020

Abstract

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.

First claim

What is claimed is:

1. A device, comprising:
an analog-to-digital converter (ADC) to convert an input signal into digital samples, wherein the ADC is configured to receive the input signal from a power grid;
a receiver to generate a pulse-per-second (PPS) signal, wherein the ADC is configured to convert the input signal into the digital samples at each of a plurality of sampling times, the plurality of sampling times being distributed between two consecutive PPS signals;
an oscillator to generate an oscillator signal having an oscillator frequency (f osc ); and
a data processor coupled to the ADC, the receiver, and the oscillator, wherein the data processor is configured to:
receive the oscillator frequency and a sampling rate (F s ) and calculate an ideal timer period register value (N ideal ) which is a number of cycles of oscillator signal between two sampling times;
calculate a timer period register value (N i ) for each two consecutive sampling times distributed between two consecutive PPS signals, the timer period register value (N i ) for a period between an (i-1) and an ith sample is determined by:

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Assignees

• Univ Tennessee Res Found

Inventors

• Liu Yilu
• Zhan Lingwei
• Yao Wenxuan

Classifications

• G01R21/00 Primary

  Arrangements for measuring electric power or power factor (G01R7/12 takes precedence) · CPC title

• G01R19/2513

  Arrangements for monitoring electric power systems, e.g. power lines or loads; Logging · CPC title

• G01R21/133 Primary

  by using digital technique · CPC title

• G01R19/2516

  Modular arrangements for computer based systems; using personal computers (PC's), e.g. "virtual instruments" · CPC title