What is energy meter
The energy meter is also called electric meters. It is an instrument for measuring active electric energy by integrating the active power with time. The appearance and development of the electric energy meter has a history of more than 100 years. Different electric meters have different measurement principles. The following is an introduction based on the development history of electric meters.
The first stage: Inductive mechanical energy meter
The internal measuring mechanism of the inductive mechanical watt-hour meter includes an electromagnetic drive unit (voltage element, current element), rotating element, braking element, bearing and counter, etc.
The inductive mechanical energy meter uses the principle of electromagnetic induction to rotate the turntable of the energy meter, and then drives the counting of the mechanical counter, so as to achieve the purpose of energy measurement. When the watt-hour meter is connected to the circuit under test, alternating current flows through the current coil and the voltage coil, and these two alternating currents generate alternating magnetic flux in their iron cores respectively, and the alternating magnetic flux passes through The aluminum disk induces an eddy current in the aluminum disk, and the eddy current receives force in the magnetic field, so that the aluminum disk gets torque and rotates (this torque is proportional to the power consumed by the load). When the aluminum disk rotates, it drives The counter indicates the consumed electric energy.
The second stage: electronic energy meter
The internal structure of electronic energy meter is composed of electronic components and integrated circuits, including current sampler, voltage sampler, multiplier, converter, frequency divider, counting display, calendar clock, core component microprocessor and power supply, etc.
The measured instantaneous voltage and instantaneous current pass through the voltage sampler and current sampler respectively, and are converted into weak electric signals proportional to them, and sent to the multiplier. The multiplier completes the multiplication of the instantaneous value of the voltage signal and the current signal, and outputs a The DC voltage signal proportional to the power, and then use the P/f converter to convert the DC voltage signal into the corresponding pulse frequency (proportional to the average power), divide the frequency by the frequency divider, and pass it through the counter for a period of time The count of the corresponding electric energy is displayed.
The third stage: Smart Energy Meter
The measurement principle of the smart energy meter is basically the same as that of the traditional electronic energy meter, but the function is more powerful: one is the wide range voltage and current measurement function, the other is the time-sharing and segmental measurement function, the third is the two-way measurement function of electric energy, and the fourth is the It has the functions of load record, event alarm, etc., the fifth is the online monitoring, diagnosis, alarm and intelligent processing functions of abnormal power consumption, and the sixth is the remote or local cost control function .
The fourth stage: smart IoT energy meter (future new star)
The smart IoT energy meter adopts the design concept of multi-core and modularization to realize the relative independence of the measurement function and the management function, and meets the access of future function expansion modules through standardized interfaces, covering the measurement module, management group, and added new functions such as harmonic measurement, Bluetooth communication , and terminal temperature measurement.
