Schweitzer Engineering Laboratories, Inc.

Daniel B Rippon

Shankar V Achanta

Raymond W Rice

Systems, methods, and devices for protecting against spoofing of Global Navigation Satellite System (GNSS) data are provided. An electronic device may include memory and one or more processors that execute instructions to cause operations to identify potential GNSS spoofing. The operations may include obtaining a first distance between a first GNSS receiver and a second GNSS receiver, obtaining first GNSS data indicating a first range measurement between a first GNSS satellite and the first GNSS receiver, obtaining second GNSS data indicating a second range measurement between the first GNSS satellite and the second GNSS receiver, and calculating a first expected range measurement between the second GNSS receiver and the first GNSS satellite based at least in part on the first distance and the first range measurement. Spoofing may be determined to have occurred based on a comparison between the first expected range measurement and the second range measurement.

GNSS authentication through multi-site observables and data comparisons

An optically powered Global Navigation Satellite System (GNSS) antenna may use a fiber-optic link to receive optical power and transmit an optical signal that contains a common time signal from one or more satellites, which may allow long-distance power and signal transmission with high efficiency and reliability. The common time signal may be used to synchronize intelligent electronic devices (IEDs) of an electric power delivery system.

Fiber-optically powered antenna

The present disclosure pertains to systems and methods for reducing startup times of line-mounted fault detectors. A line-mounted fault detector may comprise a power harvesting subsystem and an energy storage subsystem configured to store electrical energy. A fast-start power coupling subsystem may receive power from the energy storage subsystem in a startup state and provide power to a subset of components. A DC-DC converter subsystem may start up after a voltage of the energy storage subsystem exceeds a threshold. A control subsystem may transition the line-mounted fault detector to an operating state once the DC-DC converter has started and may de-energize the fast-start power coupling subsystem. The control system may enable a flow of electrical energy from the DC-DC converter to the fast-start subsystem. A fault detection subsystem in electrical communication with the DC-DC converter subsystem may communicate an indication of a fault via an RF transmitter subsystem.

System to reduce start-up times in line-mounted fault detectors

Disclosed herein are a variety of various systems and method for adaptive holdover time error estimation. In one embodiment a system may include a local time source configured to generate a local time signal and an external time source interface configured to receive an external time signal. A time source subsystem may be configured to compare the local time signal and the external time signal and to determine a temperature-dependent signal drift rate of the local time signal relative to the external time signal. The time source subsystem may be a time-dependent signal drift rate of the local time signal relative to the external time signal. A holdover subsystem may detect a loss of reception of the external time signal during a holdover period and may estimate a total maximum error based on an estimated maximum time-dependent error and an estimated maximum temperature-dependent error.

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Pullman, WA, United States of America

Daniel B Rippon