Electric Meter Line Inspection System Based On Non-contact Measurement

With the vigorous development of the real.estate industry and the increasing use of household electricity,the capacity and quantity of the ammeter are increasing as well as the demand of the accuracy and reliability of the electric energy measurement in the power supply department.It is easily led to frequent meter line problems by meter installation or alteration and unauthorizcd modification of residents,which not only results in the error of loss calculation but also brings about the electricity disputes caused by abnormal electricity.The existing solutions can only be carried out on the wire been energized and depend on the working status of the household load.It is difficult to complete the process when the breaker is off and the line is on no load.The way to resolve this case is to check the line and meter information one by one.It may be failure because of the errors about the information itself.In case of cable buried in the wall or in a confined space situation,the detection equipment will be difficult to access.According to the problems above,a meter inspection system based on the technology of non-contact measurement is presented in this paper,which is able to inspect the lines one by one in the two cases of live and no electricity.The inspection system designed in this paper mainly includes non-contact sensors,signal processing circuit,ZigBee wireless communication module and host computer display module.The entire system consists of patrol terminals and local terminals.When the line is charged,the local terminals connect to the outlet of the meter box to collect electrical data of each household.Patrol terminals carry out house-by-house inspection and receive the data from the local terminals for comparison inspection.At the same time,the inspection data sent to the host computer system to be display and storage.When the line is uncharged,the local terminals would generate a voltage signal on the line.The patrol terminals can complete inspections by detecting the signal at the household.The use of non-contact voltage sensor can solve the cases of no-load and uncharged.The feasibility of this system is proved by theoretical derivation and equivalent model establishment.Ansoft Maxwell software is used to simulate the non-contact sensing electrodes of different structures and to design the appropriate sizes and shielding structure of the electrode.By the simulation and debugging of signal processing circuit,a non-contact voltage signal measurement method is realized,while using ZigBee to build the data transmission network.In addition,this paper set up an experimental platform for the inspection system.Through the experiments of the non-contact voltage measurement module and the overall inspection system,the feasibility of this system is verified.Finally,aiming at the problem of direct access to the mode,the scheme of the wireless energy transmission technology is discussed to generate the signal source in the case of no load and uncharged,which provides a new idea for the whole process non-contact inspection.