With the continuous reduction of the earth's exploitable resources and the increase of population, the resource crisis faced by human beings is becoming more and more serious. Under this condition, the desire of human beings to find new resources is also increasing. Nuclear energy, hydropower, thermal power, wind power and photovoltaic have been constantly appearing in our vision in recent years, providing power services for our lives There are secondary or tertiary pollution in all power generation methods, such as nuclear radiation, carbon dioxide and so on, which we have to face. In this case, many countries in the world pay attention to the photovoltaic industry. As a clean and valuable resource, photovoltaic has the characteristics of small secondary pollution and high utilization rate. However, in view of the ubiquitous "bird manure" effect, the trend of monitoring the power generation of all the panels in the front of the combiner box is becoming more and more obvious. Hall current sensor can monitor the power generation of each panel or array in real time Line monitoring, so that the staff to deal with the problem in time.
Current sensor in photovoltaic inverter
Principle of Hall current sensor
The Hall current sensor is based on the magnetic balance hall principle, that is, the closed-loop principle. When the magnetic flux generated by the primary current IP is concentrated in the magnetic circuit through the high-quality magnetic core, the hall element is fixed in the air gap to detect the magnetic flux, and the multi turn coil around the magnetic core outputs the reverse compensation current to offset the magnetic flux generated by the primary current IP, so that the magnetic flux in the magnetic circuit is always zero. After special circuit processing, the output of the sensor can accurately reflect the current change of the primary side current.
Application analysis of photovoltaic inverter current sensor
(1) Photovoltaic inverter is generally divided into: series inverter; micro inverter; centralized inverter,
(2) For the application of Senko IC current sensor in series inverter, please refer to the following table:
(3) From this year, the photovoltaic inverter field will be the best time point for domestic replacement.
Characteristics of hall principle sensor
No matter the principle of open-loop or closed-loop, the basic performance of Hall sensor has little difference
1. Fast response time
2. Low temperature bleaching
3. High precision
4. Small size
6. Strong anti-interference ability
7. Strong overload capacity
The following problems should be paid attention to when selecting and using Hall current sensor:
1) Selection of current sensor:
A. When selecting the current sensor, we need to pay attention to whether there are high temperature, low temperature, high humidity, strong earthquake and other special environments;
B. When selecting the current sensor, we need to pay attention to whether the spatial structure is satisfied;
2) Problems in the use of current sensors:
A. When wiring, pay attention to the bare conductive part of the terminal block, and try to prevent ESD impact. Only engineers with professional construction experience can connect the product. The connecting wires of power supply, input and output must be connected correctly, and cannot be misplaced or reversed, otherwise the product may be damaged.
B. The product installation and use environment should be free of conductive dust and corrosiveness
C. Severe vibration or high temperature may also cause damage to the product, so it is necessary to pay attention to the application situation.