Energy feedback device suppliers remind you that frequency converters are widely used in industrial control production. They are divided into low-voltage frequency converters and medium high voltage frequency converters according to voltage levels, and the purpose and requirements of their application vary in different industries. Do you know the three major applications of frequency converters?
1. Used for non constant power loads
Due to the high starting torque of certain load characteristics, equipment that is difficult to start, such as extruders, cleaning machines, spin dryers, mixers, coating machines, mixers, large fans, water pumps, Roots blowers, etc., can all be started smoothly. This is more effective than usually increasing the starting frequency for starting. By using this method and combining it with the measures of changing from heavy load to light load, the current protection can be increased to the maximum value, and almost all equipment can be started. Therefore, reducing the base frequency to increase the starting torque is the most effective and convenient method.
2. Used for laying and signal processing
Shielded wires should be used for signal and control lines to prevent interference. When the line is long, such as a distance jump of 100 meters, the wire cross-section should be enlarged. Signal and control lines should not be placed in the same cable trench or bridge as power lines to avoid mutual interference. It is better to place them in conduit for better suitability.
3. Methods used in constant pressure water supply
Nowadays, the method of constant pressure water supply is generally adopted for water use: multiple water pumps are connected in parallel for constant pressure water supply. There are two common transformation schemes for variable frequency constant pressure water supply technology:
Save initial investment, but the energy-saving effect is poor. When starting, first start the frequency converter to 50 Hz, then start the power frequency, and then switch to energy-saving control. In the water supply system, only the water pump driven by a frequency converter has slightly lower pressure, and there is turbulence and loss in the system.
The investment is relatively large, but it saves 20% more energy than (1). The pressure of the Yuantai pump is consistent, there is no turbulence loss, and the effect is better.
When multiple water pumps are connected in parallel for constant pressure water supply, a signal series connection method is used with only one sensor, which has the following advantages:
Save costs. Just one set of sensors and PID;
Since there is only one control signal, the output frequency is consistent, that is, the same frequency, so the pressure is also consistent, and there is no turbulence loss;
More advantageous is that because the system only has one control signal, even if the three pumps are put into different inputs, the operating frequency is the same and the pressure is also the same. This results in zero turbulence loss, which means the loss is minimized, thus achieving the best energy-saving effect.