Method and system of detection of dropped loads resulting from an electrical power quality event

The method of claim 8, wherein detecting the load loss based on the result of the comparison comprises:

• determining that VA load loss has occurred based on a determination that a difference between pre-event VA measured during the pre-event interval and post-event VA measured during the post-event interval exceeds the VA load variation tolerance;
• determining that a current load loss occurred based on a determination that the VA load loss has occurred and a determination that a difference between pre-event current measured during the pre-event interval and post-event current measured during the post-event interval exceeds the current load variation tolerance;
• determining a plurality of largest pre-event harmonic currents and corresponding post-event harmonic currents and determining that any of differences between the pre-event harmonic currents and corresponding post-event harmonic currents is greater than the harmonic load variation tolerance comprising a percentage of determined current load loss;
• in response to determining that any of differences between the pre-event harmonic currents and corresponding post-event harmonic currents is greater than the harmonic current load variation tolerance, determining that a Watt load loss has occurred based on a determination that a difference between pre-event Watt measured during the pre-event interval and post-event Watt measured during the post-event interval exceeds the Watt load variation tolerance;
• and
• in response to determining that a Watt load loss has occurred, determining that a VAR load loss has occurred based on a determination that a difference between pre-event VAR measured during the pre-event interval and post-event VAR measured during the post-event interval exceeds the VAR load variation tolerance. The method of claim 9, wherein the load loss parameters associated with the captured power quality event comprise the VA load loss, the current load loss, the Watt load loss, and the VAR load loss.

A power quality monitoring system comprising:

• a plurality of loads;
• a user device;
• and
• an intelligent power device coupled to the plurality of loads and structured to monitor power quality and energy within the power quality monitoring system, the intelligent power device comprising a power supply, a display, a metering device, and a controller structured to control power quality and energy monitoring by the intelligent power device, the controller comprising a power quality monitoring device and a communication device communicatively coupled to a user device and the plurality of loads,
• wherein the power quality monitoring device comprises:
• (i) a load loss detector structured to:
• capture a power quality event occurring over a part of a plurality of time intervals each having an equal duration, the part spanning one or more time intervals;
• determine that the captured power quality event is one of a voltage sag, a swell or an interruption;
• in response to determining that the captured power quality event is one of the voltage sag, the swell or the interruption, select a pre-event interval comprising one time interval preceding the one or more time intervals and a post-event interval comprising one time interval following the one of more time intervals;
• compare a pre-event load level measured during the pre-event interval and a post-event load level measured during the post-event interval;
• and
• detect a load loss based on a result of the comparison;
• (ii) a power quality event report generator structured to generate a power quality event report including at least one of the captured power quality event, a detected load loss and load loss parameters associated with the captured power quality event and transmit the power quality event report to the user device via the communication device;
• and
• (iii) a look-up table structured to store a plurality of data for use in the power quality and energy monitoring and be accessible by a user for at least one of viewing any of the plurality of data or categorizing the captured power quality event via at least the user device.