A fault type determination method and device of a terminal unit for automation used in a power distribution network are disclosed. The method includes: for each line of incoming lines and outgoing lines of a distribution device, recording the number of faults occurring on the line; after a fault occurs, determining, according to the current and/or voltage on each line, whether automated reclosing is executed, and recording the number of executed automated reclosings; in a fault type determination period, for each line, if the number of faults occurring on the line is greater than the maximum number of automated reclosings allowed by the transformer substation side, or the fault is a repeat fault, then identifying the fault on the line as a permanent fault.

A wiring device including an interrupting device, a fault detection circuit, and a testing circuit. The interrupting device is electrically connecting one or more line terminals to one or more load terminals. The fault detection circuit is configured to detect a fault condition and generate a fault detection signal in response to detecting the fault condition. The fault detection signal being provided to the interrupting device to place the interrupting device in a tripped condition. The testing circuit is configured to determine a frequency of an input voltage at the one or more line terminals, filter the frequency of the input voltage, determine whether the filtered frequency is within a predetermined range, and when the filtered frequency is within the predetermined range, perform a test of the wiring device.

A wiring device including an interrupting device, a fault detection circuit, and a testing circuit. The interrupting device is electrically connecting one or more line terminals to one or more load terminals. The fault detection circuit is configured to detect a fault condition and generate a fault detection signal in response to detecting the fault condition. The fault detection signal being provided to the interrupting device to place the interrupting device in a tripped condition. The testing circuit is configured to determine a frequency of an input voltage at the one or more line terminals, filter the frequency of the input voltage, determine whether the filtered frequency is within a predetermined range, and when the filtered frequency is within the predetermined range, perform a test of the wiring device.

A wiring device including one or more line terminals and a controller. The controller is configured to, determine a frequency of an input voltage at the one or more line terminals, determine whether the frequency is within a predetermined range, and when the frequency is within the predetermined range, perform a test of the wiring device.

A wiring device including one or more line terminals and a controller. The controller is configured to, determine a frequency of an input voltage at the one or more line terminals, determine whether the frequency is within a predetermined range, and when the frequency is within the predetermined range, perform a test of the wiring device.

A wiring device including an interrupting device and a controller. The interrupting device electrically connects one or more line terminals to one or more load terminals when the interrupting device is in a reset condition and disconnects the line terminals from the load terminals when the interrupting device is in a tripped condition. The controller is configured to, determine a frequency of an input voltage at the one or more line terminals, determine whether the frequency is within a predetermined range, and when the frequency is within the predetermined range, perform a test of the wiring device.

A wiring device including an interrupting device and a controller. The interrupting device electrically connects one or more line terminals to one or more load terminals when the interrupting device is in a reset condition and disconnects the line terminals from the load terminals when the interrupting device is in a tripped condition. The controller is configured to, determine a frequency of an input voltage at the one or more line terminals, determine whether the frequency is within a predetermined range, and when the frequency is within the predetermined range, perform a test of the wiring device.

The present disclosure relates to a recloser control that provides autosynchronization of a microgrid to an area electric power system (EPS). For example, a recloser control may include an output connector that is communicatively coupled to a recloser at a point of common coupling (PCC) between the area EPS and the microgrid. The recloser control may include a processor that acquires a first set of measurements indicating electrical characteristics of the area EPS and acquires a second set of measurements indicating electrical characteristics of the microgrid. The recloser control may send synchronization signals to one or more distributed energy resource (DER) controllers to synchronize one or more DERs to the area EPS based on the first set of measurements and the second set of measurements.

The present invention discloses an auto re-closing device and method for an electric vehicle charging cable control device. The present invention is directed to an auto re-closing device and method for an electric vehicle charging cable control device, which are capable of stopping charging when a fault occurs and retrying to resume charging when charging is stopped.

The present disclosure relates to a recloser control that detects islanding based on a continuous analysis of frequency and rate of change of frequency. For example, a recloser control may include protection circuitry that is communicatively coupled to a recloser. The recloser control may receive measurements of an electrical characteristic in an electric power delivery system. The recloser control may determine frequency (F) and a rate of change of frequency (ROCOF) based on the received measurements. The recloser control may detect islanding of a microgrid in the electric power delivery system based at least in part on F and ROCOF. The recloser control may send a signal to the recloser to trip the recloser based on the islanding of the microgrid.