Development Of On-site User Identification And Verification Instrument For Single-phase Energy Meter

Electricity is both energy and commodity,which is closely related to people’s life.As the most common meter of electric energy measurement and related economic settlement,electric energy meter has direct influence on the interests of power supply department and users.Our country has also classified the electricity meter into the compulsory verification meter,which needs to be checked before putting into use,and the power supply station should also conduct the second detection of the electric energy meter regularly during use.In addition,there is still a situation where the electricity meter and the user are wrongly connected and even the phenomenon of illegal electricity,so the electricity management department must be able to make an accurate judgment on the connection between the electricity meter and the user.In view of the above situation,this paper proposes the development of field user identification and verification instrument for single-phase electricity meter.It realizes the function of combining power meter calibration and user identification,and solves the problem of two instruments detection in the past.The single-phase energy meter on-site user identification and verification instrument has three major functions: electrical energy calibration,electrical parameter measurement,and user identification.The electrical parameter measurement function uses the synchronous sampling method to sample the electrical signal,and the FFT calculation of the sampled value yields the effective value and phase of the voltage and current data.The energy check function uses non-simultaneous sampling methods to sample electrical signals,and directly accumulates energy at each sampling point to obtain total electrical energy.The energy calculated by this method is affected by the frequency fluctuation of the signal.The user identification function is implemented by combining the power carrier communication technology with the pulse current identification method.Compared with the single power carrier communication technology,the recognition result is more reliable.The whole system consists of two parts: the calibrator and the pulse current generation device,both of which are powered by the AC-DC power module.The calibrator uses the STM32F407CZGT6 chip as the control and data exchange center,and which is equipped with 16 high precision A/D chip ADS8568 to sample the electrical signals.The pulsed current generation device is designed with the STM32F103C8T6 chip as the core,and uses the on-chip ADC to non-synchronously sample the electrical signals in the power grid.Based on thesampling value,The pulsed current generating circuit generates a pulsed current signal with a pulse width of 500 us and a frequency of 10 Hz.The calibrator is equipped with a WIFI communication module that can communicate with mobile communication terminals such as mobile phones,and which give full play to the advantages of mobile phones and network technologies,and provide data for power system user information management.The device is tested by the bd-3d multi-function calibrator at the level of 0.05,and the test results show that the accuracy level is 0.2,which has reached the precision requirement of the common electric energy meter.When the design device is used for user identification,There is no need to power off the user’s home,and the electrical appliances can work normally,so as to avoid unnecessary troubles to users.