Method for evaluating small current variable by apparent power

Abstract

The invention discloses a method for evaluating a small current variable by apparent power, and belongs to the technical field of electromagnetic measurement. The method comprises the steps of S1, detecting a small current on a line; S2, collecting the current detected in the step S1, and multiplying the current by a given apparent voltage to obtain apparent power; S3, accumulating the apparent power obtained in the step S2 in real time to obtain apparent electric quantity; and S4, reading the apparent electric quantity in the step S3 once at an interval T, calculating the variation of the apparent electric quantity in each time period, comparing the relative variation amplitude of the apparent electric quantity variations in two adjacent time periods, and making a decision of continuing to detect or report according to the relative variation amplitude. According to the judgment method, the change trend of the damage energy in the line is automatically judged according to the change amplitude of the apparent electric quantity in the adjacent same-length time periods, the development situation of the damage energy is mastered, and an early warning signal is given when the increase amplitude is large, so that workers are reminded to take security check measures, safe production is ensured, the waste of raw materials is avoided, and the loss is reduced.

Description

technical field [0001] The invention belongs to the technical field of electromagnetic measurement, and in particular relates to a method for judging small current variables by using apparent power. Background technique [0002] Since the end of the 1960s, in order to strengthen the safety of electricity use, my country has gradually adopted protection measures in the power system, among which the leakage protector is a general technical means. The leakage protector detects the abnormal current or voltage signal of the monitoring equipment or the circuit. When the detected signal reaches its set threshold, it prompts the actuator to act to cut off the power supply, so as to avoid accidents such as burning out electrical appliances, fire or electric shock, so as to ensure personal safety and health. To ensure the safety of electrical equipment and achieve the purpose of protection. [0003] Later, some adopted the low-current grounding method, which installed a zero-sequence...

AI Technical Summary

Problems solved by technology

[0005] It can be seen that technologies such as leakage protectors and low-current grounding can no longer meet the needs of power grid development. It is urgent to develop a new detection technology that can actively find problems to avoid disorderly power outages, achieve safe and energy-saving production, and reduce waste.

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