System and method for identifying user change relationships in low-voltage power distribution based on power-frequency voltage distortion

Abstract

The invention discloses a system and method for identifying user change relationships in low-voltage power distribution based on power-frequency voltage distortion. The method includes the following steps of: step 1, signal modulation: after a distribution transformer, a low-voltage line, an end user and two modulation demodulation devices are connected, the system is started, the user end triggers a silicon controlled rectifier around 150 degrees of a power frequency voltage cycle, and therefore, short-circuit current i can be generated between a low-voltage side phase line and a low-voltage side null line, and the magnitude of the short-circuit current i is determined by L2, R2 and the turn-on time of the silicon controlled rectifier; step 2, signal demodulation; and step 3, information exchange. The system and method of the invention are improved based on TWACS technologies. According to the system and method of the invention, a current modulation technique is utilized, and voltage distortion caused by current modulation is fitted, so that threshold values of various kinds of typical transformer areas can be automatically selected; and the number of non-distortion cycles between adjacent distortion cycles is utilized to transfer information; and therefore, the method for identifying the user change relationships in a low-voltage power distribution system can be realized. With the method of the invention adopted, effective and reliable means can be provided for electricity utilization management departments in the realization of user archive establishment, verification and the like.

Description

technical field [0001] The invention relates to a system and method for identifying the relationship between low-voltage power distribution household transformers based on power frequency voltage distortion, and belongs to the field of power distribution automation. Background technique [0002] In the business management of the low-voltage distribution network, the power management department often needs to check user files to ensure that the files are accurate and provide correct management data for marketing management, including user file ownership, network topology, and user equipment power consumption. Phase and working phase sequence, etc. These data are the basic data to ensure the balance of electricity load in the station area, reduce the unbalanced load loss, and ensure the correctness of line loss in the station area. They are the basic elements for realizing the construction of smart grid. [0003] Products currently on the market for the above purposes are main...

AI Technical Summary

Problems solved by technology

However, the grounding systems in the United States, Canada and other countries use high-current grounding systems, while my country uses low-current grounding systems. In addition, the power grid environment in my country is poor and the interference is serious. The original TWACS technology is not suitable for my country.

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