1. Use of inverter
Inverter, it is produced in the 1960s, with the rapid development of high-power transistors and the rapid development of integrated circuits, making the performance of the inverter have greatly improved. Because the inverter has a stepless speed regulation capable of achieving the constant torque and constant power of the asynchronous motor, the speed range is wide, the smoothness is good, the mechanical characteristics is harder, and the energy saving effect is obvious, which is advantageous for automatic control. The applications of the inverter are getting wider and wider, basically covers all fields.
2. Application of inverter in production
Overall, the inverter is mainly to speed up the motor in industrial production. So what is the advantages compared to the frequency conversion speed and traditional speed control? There are two main points: First, it is easy to implement automatic control. The inverter is the combination of power technology and electronic technology, and is also a strongly weak electric organic integral, which has a congenital advantage in achieving automatic control; second, it is possible to save energy consumption. The following is analyzed as an example of a constant pressure circulating water system.
3. Application of inverter in automatic control system
In the circulating water system, since the water time and water flow rate of each workshop and the department are different, the water pressure in the system will change, which requires that the water pressure in the entire system remains constant according to different water conditions. . Solving this problem generally has the following practices.
First, the water flow is limited to the water flow, thereby achieving the purpose of limiting water pressure. This method has several disadvantages. First, the precision accuracy of the water valve is insufficient, the fluctuation range of the water pressure is large; second, it is not easy to realize automatic control, and it is not convenient for real-time monitoring.
Second, the water tower is cultivated, and the liquid pressure is used to maintain a constant water pressure. Compared to the former method, the pressure is constant, but it is still not convenient to achieve automatic control and real-time monitoring, and the area is large, and the generality is poor.
The system uses negative feedback closed-loop control systems with respect to the first two methods.
We installed the pressure sensor as a feedback signal in the line of the circulating water system, and then compared the sampled water pressure to the given water pressure, regulating the frequency of the inverter according to the error obtained. Thus, the rotational speed of the control motor is achieved, and finally controlling the pressure of the entire circulating water system remains constant.
From the above analysis, use the inverter’s closed-loop control system, due to the inverter’s response characteristics, the control is more convenient, accurate, versatile, and the operation interface is also more friendly.
> The role of the inverter in the depletion
There is always a debate on the role of the inverter in energy saving and consumption. I think that cannot be generalized, depending on the situation.
For textile machining, rolling, steel, etc. In these occasions, non-energy conservation, and because the inverter is high cost, it also has energy consumption, which makes the entire system more expensive and energy consumption.
However, in the style of wind turbine, water pump and other applications, the energy saving and consumption consumption characteristics are very obvious. In these occasions, the load is often changed. If multiple motors are used in parallel, it will increase the cost of equipment, and the traditional speed control method is also not easy to implement automatic control. Therefore, there are many Changchun Hongbao manufacturers to produce special inverters for such applications. Since such inverters do not require high speed and torque control characteristics, the cost is also low.
> Energy saving by frequency conversion adjustment axis power
In a system that uses a water valve-controlled pressure, the motor is always operating in the rated power, and the control method of system pressure is to adjust by adjusting the opening and opening of the waterway valve, the energy generated by the excess power is consumed in the overcome valve. The resistance is finally converted to thermal energy being absorbed by the system. When the inverter is used, whenever the amount of water changes, if the motor keeps the original speed constant, the system pressure will change, at which time the pressure sensor in the system will feed back the detected pressure signal to the controller, when the system After the pressure of the pressure is exceeds the allowable range, the controller will down to the inverter to change the operating frequency of the motor, thereby adjusting the motor speed. Knowledge from fluid mechanics we know the flow W speed, pressure W speed C2, and shaft power W rotational speed C3. When the motor is operating at the maximum amount of water, when the amount of water is lowered to 80% of the maximum water content, the rotational speed becomes 80% of the rated power. At this time, the axis power can be lowered to the rated power 51.2. %. It can be seen that the energy saving effect when using the inverter is quite obvious.
> DC bus from the regenerative brake unit or the inverter can be used in parallel to the power feedback to the power grid to use the power supply to other devices.
In addition, the frequency converter is speedable, and the start current is limited to 150% rated current as the motor is increased, and the starting current is limited to 150% rated current (depending on the model, 125% to 200%). When the power frequency power is directly activated, the start current is 6 to 7 times the rated current, and therefore, the impact of mechanical electrical electricity will be generated. Therefore, the drive transmission can be smoothly started (the starting time is growing), and the impact of the large current to the motor is reduced, and the grid current is guaranteed.
In summary, through the above analysis, it can be seen that the inverter has a very broad application space in production, as long as we are reasonable, carefully designed, you can get an efficient and intelligent system.
Changchun Hongbao is an export-oriented enterprise specializing in research, development, production, sales and technical services in power field products.
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