Features of frequency conversion air compressor

6.1. Save energy? Reduce electricity consumption? Improve corporate competitiveness  

7.§Air compressors and air conditioners often account for more than 30% of the company's electricity consumption.  

8.§Introduce energy-saving facilities as early as possible to reduce production costs, create profits and enhance corporate competitiveness. 

  9.2. Save energy? Reduce electricity consumption? Improve corporate competitiveness  

10.§According to the survey, corporate energy and electricity consumption are the last and biggest uncontrollable costs. 

  11.§ Electricity is mainly used for power, that is, electric motor. 

  12.§Public equipment using electric motors mainly include air compressors, air conditioners, water tanks and fans.  

13.§Air compressors and air-conditioning hosts are the big tigers among them.  

14.3. The National Development and Reform Commission launched ten key energy-saving projects  

15.§Energy saving project of motor system???  

16.§Promote variable frequency speed regulation energy-saving technology, adopt variable frequency speed regulation energy-saving measures for general mechanical systems such as fans, water pumps, and compressors??? 

  §During the "Eleventh Five-Year Plan" period, the motor system's operating efficiency will be increased by 2% to form annual power saving capacity 20 billion kilowatt hours. 

  4. Air compressor power saving measures 

  17.§ Reasonably plan the compressed air pipeline to reduce pressure drop.    

                                              18.§Strictly prevent pipeline leakage.  

19.§Use high-efficiency leak-proof automatic drain.  

20.§Use interlocks to control load management. 

  21.§All of the above are important topics for air compressor power saving.  

§There is another most important and effective measure...  

22.6. What are the sales advantages of air compressors? 


24.§good service

25.§High cost performance  

26.§Abundant parts 


28.7. The basic control method of traditional fixed speed screw air compressor   

29.§Add load release mode.  

30.§The pressure reaches the upper limit to discharge the load. 

  31.§Load when the pressure reaches the lower limit  

32.§It is the simplest basic control method, but there are often shortcomings such as unstable pressure and frequent loading and unloading.   

33.§Air intake capacity adjustment mode. 

  34.§Automatically adjust the opening of the intake valve with the increase or decrease of air consumption. 

  35.§The pressure is relatively stable. 

  36.§Additional function belonging to load and release mode 

  37.§The machine runs smoothly  

38.8. Traditional loading and unloading and air intake capacity adjustment control system  

39.§       The solid green line is the loading and unloading energy consumption curve assuming that the system's gas storage volume is infinite. 

  40.§Loading energy consumption is 100%.  

41.§Unloading energy consumption assumes 40%. 

  42.§The actual energy consumption curve is between the green curve with greater curvature and the green solid line.  

43.§Loading and unloading control is theoretically more power-saving than intake air volume control, but...if the air storage system is too small...the power consumption of loading and unloading control is even more amazing.

44.45. The gas storage system is too small...loading and unloading control consumes more power    45.§The smaller the gas storage system, the more frequent the compressor loading and unloading.  

46.§The screw air compressor needs to discharge about 2% to 3% of the air production volume from the relief valve every time the load is discharged. 

  47.§If the air compressor is loaded and discharged every ten seconds, it will waste 12%-18% of the gas production. 

  48.§If the air compressor is loaded and discharged every 30 seconds, it will waste 4% to 6% more air production.  

49.46. ​​Traditional loading and unloading and air intake capacity adjustment control system  

50.§       The blue solid line is the energy consumption curve of air intake capacity adjustment.  

51.§100% energy consumption when air consumption is 100%. 

  52.§70% energy consumption when the gas consumption approaches 0%.  

53.§The air intake capacity adjustment range is not suitable for operation approaching 0%, so after the capacity adjustment reaches a certain proportion, it still needs to return to the basics... enter the loading and unloading mode. 

     54.Because of the pressure and stable operation, users often think that the compressor is at full load. In fact, it is squandering your company's precious money under partial load.

55.47. Compressor power consumption ≠ compressor gas production  

      56.§Unless...using stepless frequency conversion control technology 

  57.48. Description of frequency conversion energy-saving control system and air compressor frequency conversion principle   

   58.49. Working and frequency conversion switching circuit  

       59.50. Advantages of frequency conversion air compressor  

60.§The pressure accuracy is below 0.1kg/cm2. Note: Accuracy refers to the FUZZY control accuracy, not including the empty upper limit setting value. 

  §Reducing the speed of the compressor unit to reduce the load proportionally, and the energy saving effect is 100%.  

61.§Reducing the speed under partial load can extend the life of the unit. ??? 

  62.§Soft start, no starting high current.  

63.§When multiple units are in operation, you only need to install one or more of them to fully monitor the pressure of the system.    

      64.51. Description of frequency conversion energy-saving control system and air compressor frequency conversion principle The red solid line represents the frequency conversion energy consumption curve.  

65.·Assuming that the lowest frequency is 25 Hz.

66.·When the gas consumption is lower than the lowest frequency gas production, the compressor is loaded and unloaded.

67.52. Description of frequency conversion energy-saving control system and air compressor frequency conversion principle  

§The energy consumption of the inverter compressor is proportional to the gas output when the inverter is in frequency.  

68.§Considering the safety factor and peak gas consumption, the rated power of the compressors we purchase is often at least 30% to 50% larger than the average load.  

69.53. Energy-saving advantages of variable frequency air compressors 

  70.§Assuming an average load ratio of a 75kW air compressor is 60%. 

  71.§Running in the intake air volume adjustment mode, the power consumption is 88%=66kW.

   72.§The average speed is 60% after the transformation to frequency conversion and the average power consumption is also 60%=45kW. 

  73.§The horsepower difference between the two controls is up to 21kW.  

74.54. Energy-saving advantages of variable frequency air compressors  

75.§Assuming that the electricity bill is 0.7 yuan per kilowatt-hour.  

76.§8400 hours of operation per year.  

77.§One year's electricity bill can save RMB 123,480.00.  


79.55. The power-saving advantages of variable frequency air compressors

     80.56. Parallel operation mode of traditional control and frequency conversion system     

     81.§The frequency conversion machine is used as a variable capacity host: leading load and finally stop.  

82.§The frequency conversion power of the same pipe network should preferably be higher than one-third in order to cover the change of gas consumption. 

  57.Parallel operation mode of traditional control and frequency conversion system   

   83.Frequency conversion machine as a variable capacity host: lead load and stop at the end.

58. Comparison of dedicated frequency conversion cabinets for silicon-based screw machines and non-professional products Poor stability, poor ratio, power saving, more power consumption, more power consumption, simple pressure adjustment, difficult pressure adjustment, easy parameter adjustment, difficult parameter adjustment, difficult parameter adjustment, easy maintenance, difficult maintenance? Simply change the air compressor manually Those with upper frequency limit will not be compared.

The difference of frequency conversion air compressor  



§Comparison between permanent magnet motors and induction motors used in air compressors.doc

   §Quotation payment.doc  

§Comparison between inverter compressor controller ICU5000S and PID control.doc 

         Frequency conversion cabinet dedicated for screw air compressor  

§Suitable for all oil screw machines and water-lubricated oil-free screw machines.  

§Suitable for centrifugal pumps and fans.  

§Accurate control, stepless frequency conversion, equal ratio energy saving. 

  §Do not change the operating mode of existing compressors.  

§With frequency conversion and fixed frequency switching function. ?  

§The optional type can control two compressors with frequency conversion.

   §Complete filtering and anti-noise circuits are enclosed.  

Industrial and frequency conversion switching circuit

     Comparison of dedicated frequency conversion cabinets for silicon screw machines and non-professional products Poor proportional power saving is more power-consuming, more power-consuming voltage and power adjustment Simple pressure adjustment is not easy Pressure adjustment is difficult No comparison.

91. True frequency conversion?? False frequency conversion?   

   §       The pink ladder line is the frequency hopping theoretical energy consumption line.  

§When the air volume changes slightly, the operating frequency will easily swing up and down and cause oscillation. 

  §The actual situation will be more energy-consuming because the system is unstable and the ladder moves online. 

  §If you use PID control, it is not easy to set the parameter value:  

  §Stabilization and energy saving are difficult to balance. ? 

  §Professionals are required to adjust any working conditions. If it is not adjusted properly, it will consume more power than the air intake capacity adjustment. 

  92. ICU5000S controller   

       §Single-chip microprocessor.  

§Large LED display setting and operating pressure can directly change the pressure setting value.  

§It can be used as the control panel of frequency conversion air compressor. 

  §It can be fully compatible with the existing compressor control panel.  

93. Special frequency conversion cabinet for silicon screw machine   


§Voltage: 380V  

§Horsepower: 22kW–300kW  

§With frequency conversion and Y-△ switching function (type 2 machine).  

§The three-type machine is optional, which can drive the two machines into frequency conversion.  

§There are also special types for centrifugal pumps and fans.  

      94. Comparison of built-in and modified inverter air compressors  

            34. Frequency conversion transformation FAQ 

  §The influence on the motor:

   §Motor temperature rise will be higher when driven by frequency conversion, so the minimum speed of the air compressor must be limited. 

  §ICU5000S control technology can reduce the current in equal proportion, and the insulation grade of the existing motors is at least Class F, so unless the insulating paint is on the verge of deterioration, the minimum speed can be set at 50% or more. 

  §PWM carrier will produce high frequency whistle but will not damage the motor.  

§If the ambient temperature is too high, a cooling fan can be installed   

35. Frequency conversion transformation FAQ  

§The impact on the life of the body:

   §The life of the air compressor body is inversely proportional to the speed. 

  §The average speed decreases after the frequency conversion, so the service life must be prolonged. 

  §The oil screw machine uses differential pressure to supply oil, so the lubrication effect will be better at low speed.  

36. Frequency conversion transformation FAQ  

§Impact on lubricating oil system:   

§The frequency conversion transformation does not change the lubricating oil system. 

  §The average load is reduced after frequency conversion transformation, and the lubricating oil system is easier to dissipate heat.  

§The probability of high exhaust temperature decreases.  

§The running quality of lubricating oil is more stable. 

  37. Frequency conversion transformation FAQ  

38. § Impact on unit accessories:  

  39. § For air intake filters, oil filters and oil and gas separators, the service life will be more stable because of stable operation, reduced loading and unloading times, and reduced impact after the frequency conversion transformation.  

§No adverse effects on other unit accessories. 

  38. Frequency conversion transformation FAQ 

  §Impact on the power grid:  

  §If the harmonics and noise of the inverter are not properly suppressed and isolated, they may interfere with the power grid. 

  §The company's frequency conversion cabinet is equipped with an isolated power supply control system, a complete filter circuit, and a reactor to protect the pipe network and the frequency converter; therefore, the interference to the power grid can be eliminated to the minimum.  

39. Frequency conversion transformation FAQ 

  §Impact on compression efficiency:   

§The efficiency of the rotor of the oiled screw machine is the highest when the tangential speed is 18-20m/s.  

§Considering the market competitiveness and scope of application, manufacturers generally make the rotor of the oil screw machine run at a tangential speed of about 35m/s. 

  §So compression efficiency becomes better after frequency conversion.  

40. Frequency conversion transformation FAQ  

§Impact on site operation:   

§After the frequency conversion modification and adjustment are completed, all air compressor operations and protections are still carried out on the existing control panel.  

§No change is that the motor overload protection is transferred to the inverter.

41. Various starting current curves  

44.VDT1216 controls exhaust temperature with dew point  

§Oil screw compressors need to set an operating discharge temperature higher than the pressure dew point to avoid lubricating oil emulsification. At present, all compressor manufacturers use oil temperature control valves to fix the exhaust temperature at a certain high temperature according to the summer high temperature and humidity environment. 

  §Actually, the compressor discharge temperature can operate normally as long as it can be higher than the pressure dew point temperature, and the lower the discharge temperature, the higher the compression efficiency. The company's inverter compressors use VDT1216 dew point temperature controller to increase the total compression efficiency by more than 6%. (This function is optional.)  

45. The pressure dew point varies from place to place