Strong-magnetism electricity stealing prevention method

Abstract

The invention discloses a strong-magnetism electricity stealing prevention method. The method comprises the following steps of: firstly, connecting a Rogowski coil in parallel to an electromagnetic current transformer in an electric energy metering device, and acquiring signals IkA of the Rogowski coil and signals IkB of the electromagnetic current transformer in real time; secondly, performing analog-digital conversion on the IkA signals and the IkB signals at the same time; thirdly finding a waveform phase zero point to adjust a waveform of the Rogowski coil and a waveform of the electromagnetic current transformer so as to compare data of the two waveforms at the same time, thereby determining whether strong-magnetism electricity stealing exists; and alarming when the strong-magnetism electricity stealing is detected. The strong-magnetism electricity stealing prevention method accurately determines behavior of the strong-magnetism electricity stealing by using the Rogowski coil withlow detection precision, and has the advantages of simple operation, low cost and high efficiency or the like.

Description

technical field [0001] The invention relates to a method for preventing electric stealing by strong magnetism. Background technique [0002] With the deepening of the market-oriented reform of the power industry, power companies have begun to shift their focus to creating and maintaining their own economic benefits, which has also prompted them to pay more attention to the abnormal problems of power metering devices. With the development of science and technology, more and more high-tech stealing methods have troubled power companies. Strong magnetic stealing is one of them. Strong magnetic stealing uses the mutual inductance of the magnetic flux of a strong magnet on the energy meter. The transformer interferes to make the transformer magnetically saturated, so that the transformer in the meter cannot sense the current or the induced current is smaller than the actual current, thereby achieving the purpose of stealing electricity. [0003] In view of the emergence of this ...

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Problems solved by technology

[0007] Among the above methods, although the first scheme monitors the operation status of the electric meter, it can theoretically monitor all stealing behaviors on the electric meter side, but the electric meter needs to be refitted, the structure is complicated, and the cost is relatively large.

Moreover, the sensitivity to strong magnetic stealing behavior is not enough, and it may not be possible to judge strong magnetic stealing

Option 2 Although the monitoring circuit is specially designed for strong magnetic stealing, but because the monitoring circuit is too simple, it is easy to cause misjudgment due to natural magnetic field or non-human factors, and the effect is poor.

Although the third option can more accurately determine the strong magnetic stealing behavior, the signal of the Hall effect sensor is easily affected by temperature, and the Hall device is also affected by the interference of the external magnetic field, and the cost of the entire system is relatively high, which is not suitable for mass popularization.

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