A system and method for detecting and isolating a high-altitude electromagnetic pulse (“HEMP”) along electrical lines electrically connected to a monitored infrastructure so as to protect the monitored infrastructure, the method including a phase unit receiving sensor signals from a plurality of sensors electrically connected to each of the electrical lines, respectively, upstream of and associated with the monitored infrastructure. The method includes determining if the received sensors signals associated with the respective electrical line is indicative of an E1 component of an EMP and, if so, actuating an isolation subsystem in less than 300 nanoseconds to electrically isolate the respective electrical line against propagation against the monitored infrastructure. Determining in real time if received sensor signals is indicative of the E1 component includes a hardware implemented neural network (NN) having algorithms for machine learning (ML) and artificial intelligence (AI) operable to provide instantaneous detection and classification.

A filter design configured to operate in the medium voltage range of 1000 to 5000 volts, provides protection against Electromagnetic Pulse/High Altitude Electromagnetic Pulse (EMP/HEMP) intentional electromagnetic interference pulses. The filter utilizes no oil filled components to preclude the catastrophic failures (explosions) during operation. Many of the components incorporated in the present design are suited to absorbing harmonics without failing. In addition to mitigating E1 and E2 pulses, the filter is resistant to line harmonics which have proved to cause filter failure in past designs. The filter provides EMP/HEMP conducted pulse protection for downstream electronics inside hardened shelters for medium and high voltage applications.

Embodiments of a single event latch-up (SEL) protection circuit are provided, including: a first circuitry block coupled to a source of an input voltage a load, and digitally controlling a first switch; the first switch generates a load and senses an instantaneous load current iLoad. A second circuitry block is configured to generate an average iLoad and generate single event latch-up triggers (i.e., SEL fault detection) as a function of at least a comparison of the inst_iLoad and average iLoad; wherein this first circuitry block contains the analog based SET filtering needed to reduce false SEL triggers. A supervisor module generates on/off commands for the first switch, responsive to receiving the SEL detection in excess of a preprogrammed delay to provide the final SET filtering to prevent false SEL triggers. The first circuitry block removes the load voltage at N1 upon receiving an off command from the supervisor module.

Systems and method for automated self-testing of a protective device for a transformer are disclosed. One system includes a protection circuit electrically connected to a transformer neutral, the transformer electrically connected to a power grid, the protection circuit may include a DC blocking component, a switch assembly, and a spark gap assembly each positioned in parallel between the transformer neutral and ground, a switch assembly. The system may further include various testing circuits configured within the protection circuit and switches which when actuated inject a signal to test various components in the protective device.

A control device for an electrical protection circuit for use in an alternating current system including a transformer is disclosed. An example system includes a first measurement probe, a second measurement probe configured to measure an electrical property within the electrical protection circuit, and a control module, including a processing device. The control module is configured to monitor a measurement from the first measurement probe and transmit a protection activation control signal to the switch assembly based on the measurement from the first measurement probe exceeding a first predetermined threshold. The control module is also configured to monitor a measurement from the second measurement probe and transmit a protection deactivation control signal to the switch assembly based on the measurement from the second measurement probe satisfying a second predetermined threshold.

An electric power substation includes a circuit breaker, an electromagnetic pulse mitigation module coupled to the circuit breaker and comprising a continuous conductive enclosure that is impervious to radiated or coupled electromagnetic energy, an input/output device housed within the electromagnetic pulse mitigation module, and a control house communicably coupled to the circuit breaker via a primary communication line and housing one or more primary relay panels.

An electric power substation includes one or more primary relay panels located at a substation site and susceptible to damage caused by radiated or coupled electromagnetic energy, and an electromagnetic pulse mitigation module located at the substation site and comprising a continuous conductive enclosure that is impervious to the radiated or coupled electromagnetic energy. One or more backup relay panels are housed within the electromagnetic pulse mitigation module and capable of assuming operation of the one or more primary relay panels.

A system and method for suppressing EMP-induced electrical system voltage surges due to detonation of a nuclear weapon, the EMP comprising E1, E2, and E3 component pulses. A plurality of shunting assemblies, each including MOVs, gas discharge tubes, other mechanical, electrical and ionization discharge devices and combinations thereof, detect and react to the overvoltage according to timing parameters associated with each of the E1, E2, and E3 components and shunt the overvoltage to decrease to under a predetermined allowable level. Respective shunting assemblies may include automatic self-monitoring of any faults in respective circuitry and also a challenge mode for on-demand circuit monitoring using an optical coupling switch, the optocoupler including an infrared light supplied by an LED flashlight and having a phototransistor light receiver.

An integrated circuit (IC) chip having circuitry adapted to detect and unlatch a latched transistor, and methods for operating the same are provided. In one example, an IC chip includes a body, a power rail disposed in the body and coupled to at least one of a plurality of contact pads disposed on the body, and a first core circuit disposed in the body. The first core circuit includes a first current limiting circuit, a silicon controlled rectifier (SCR) device having a first transistor, a second transistor, and a first latch sensing circuit. The first current limiting circuit is coupled to the power rail. First terminals of the first and second transistors are coupled to the first current limiting circuit. The first latch sensing circuit has a first input terminal coupled to second terminals of the first and second transistors. The first latch sensing circuit also has an output terminal coupled to the first current limiting circuit.

Cellular tower sites generally include a remote radio head conductively connected to a base station. A system for protecting the site from an electromagnetic pulse (EMP) includes an antenna array; an EMP detection circuit in communication with the antenna array; and a disconnect switch in communication with the EMP detection circuit. The disconnect switch is conductively connected between the remote radio head and the base station; when opened, it physically interrupts the connection between the remote radio head and the base station. For instance, if a comparison, within the EMP detection circuit, between the pulse duration and/or frequency of an electromagnetic signal received by the antenna array to the frequency and/or pulse duration of an EMP E3 signal component determines a match, the EMP detection circuit can output an EMP detection signal to the disconnect switch, thereby disconnecting the remote radio head from the base station.