How to realize remote control of smart meters
With the development of chip manufacturing and Internet of Things technology, many devices for metering and charging in life have changed accordingly. Electric meters, water meters, gas meters, and heating have all realized remote data collection and control. This not only greatly saves labor, but also more precise data processing and statistics.
Mechanical electric meter
In the early days, purely mechanical electric meters, also called induction meters, were used. It uses the principle of electromagnetic induction to collect current and voltage, drives the count through the transmission of mechanical gears, and finally displays the power consumption. Its interior is mainly composed of several parts such as current coil, voltage coil, aluminum plate, permanent magnet, mechanical counting device, and connecting terminal. Among them, the voltage coil is connected in parallel in the load circuit, this coil has more turns and the wire diameter is small; the current coil is connected in series in the load circuit, its coil turns are few, and the wire diameter is thick. The magnetic flux generated by these two coils acts together on the aluminum plate. Due to the action of these two coils, eddy current will be generated in the aluminum disk, which will rotate the aluminum disk. Under the damping action of the permanent magnet, the aluminum disk will rotate at a constant speed. Driven by the worm and gear, the counting device will count and display Power.
Since the induction meter uses mechanical devices for measurement, the mechanical devices will be affected by environmental factors (such as temperature). Therefore, the stability and measurement accuracy of this kind of meters are relatively poor, and each meter will have differences in magnetic circuit and mechanical structure when leaving the factory, so some compensation measures need to be added. After a long period of transportation and vibration, adjustments are also required. school.
This kind of electric meter needs to drive the aluminum sheet to rotate during measurement, which generates high power consumption and cannot prevent abnormal usage such as electricity theft. It requires manual meter reading on a regular basis, which will also greatly increase the workload and electricity consumption statistics. time. So this kind of electrical performance has basically been eliminated.
Electronic meter
The electronic electric meter is a kind of electric meter that appeared after the induction electric meter. It is smaller in size and lighter in weight. The measurement of electronic meters still needs to detect voltage and current. Voltage is generally detected by means of resistance divider, and current is detected by sampling resistance, so that the collected load current will be converted into voltage through resistance. The metering of this kind of electric meter does not use an aluminum plate with a mechanical structure, but inputs the voltage and current sampling signals to a dedicated metering chip. The metering chip will multiply the input voltage and current signal and convert it into a pulse signal proportional to the product. The power display part still uses a mechanical roulette. Unlike the induction meter, it uses an electromagnetic counting device. The pulse output from the metering chip drives the mechanical device of the power display part to display the final power consumption.
Compared with induction meters, electronic meters have improved measurement accuracy and are less affected by the environment. They are easy to calibrate, and their measurement accuracy will not be affected by factors such as vibration during transportation. Due to the use of chip measurement methods, their own power consumption It will also be reduced, and this kind of meter can be added to the detection of abnormal use such as electricity theft. Although this kind of electricity meter is superior to the induction meter in many aspects, it still requires manual meter reading and statistics on electricity consumption.
Card prepaid meter
The metering and power display functions and principles of the plug-in prepaid meter are basically the same as those of the electronic meter. The difference is that it adds a charge control function to the ordinary electronic meter. When in use, it is necessary to use an IC card for "pre-charge" operation, which is generally operated by the power supply department or the community power supply management department.
Compared with ordinary electronic representatives, this kind of electricity meter can effectively control the user's electricity consumption behavior due to the addition of a pre-charged fee control system, such as power failure when arrears, abnormal power consumption control, etc. Wait. Due to the prepayment method, manual meter reading is not required, and when the user performs the card reader recharge operation, the data in the meter will be uploaded to the recharge operation platform through the IC card, so that the user’s electricity consumption and Statistics on electricity consumption.
As the prepaid meter saves the trouble of manual meter reading, the pre-recharge still requires manual operation, and for safety, this recharge operation can only be done by authorized departments, so there will still be inconveniences in use.
Smart remote meter
This kind of electric meter is a commonly used electric meter nowadays, it removes the prepaid card operation. Compared with ordinary electronic meters and plug-in meters, its collection and measurement parameters are more abundant, and a variety of measurement information can be displayed through the liquid crystal, such as total power consumption, peak and valley power consumption, power consumption, and so on. In addition to displaying local information on the LCD screen, smart meters can also perform manual meter reading through infrared communication and remote meter reading through data interfaces.
There are many ways of remote data transmission and control signal transmission of smart meters, such as store power carrier, public network transmission, etc. The latter are mostly used and relatively stable. The data collection interface of the electricity meter is generally RS485, and the electricity meter in a small area (such as a unit) will be connected through RS485 according to the division of the area. The data concentrator collects and processes the data of the electric meters in the area, and uploads the collected data to the server of the electric power department through the public network (such as GPRS). After the data is processed and analyzed by the server background software, it can be used as electricity In addition to departmental supervision, electricity consumption and cost information will also be pushed to users through information and other methods. In addition to the remote collection of electricity consumption information, only electricity meters can also monitor and control electricity usage behavior. When abnormal electricity usage behavior occurs, it can be powered off by remote control, and the background software can send reminders and notify management department.
