Chinese VFD (Variable-frequency Drive) energy-saving advantages are highlighted, and the market space is broad

Frequency conversion technology was born in response to the need for stepless speed regulation of AC motors, aiming to realize AC control by changing the frequency of AC. With the development of computer technology and power electronics technology, the application of low-voltage VFD (Variable-frequency Drive) has also been rapidly developed. The use of VFD (Variable-frequency Drive) speed regulation can improve the control precision of machinery, production efficiency and product quality, and reduce energy consumption at the same time.

Significant energy saving effect by using frequency conversion technology

Since its research and development, frequency conversion technology has achieved remarkable energy-saving effects in many production processes. Chinese national "12th Five-Year Plan for Energy Conservation and Emission Reduction" requires the implementation of energy-saving renovation projects. Energy-saving motor systems are one of the main projects. System operation and control, improve the overall operating efficiency of the system. The plan proposes that the operating efficiency of the motor system in 2015 will increase by 2 to 3 percentage points compared with 2010, and an electricity saving capacity of 80 billion kWh will be formed during the "Twelfth Five-Year Plan" period. Therefore, since the "Twelfth Five-Year Plan", energy conservation and environmental protection have been the core of Chinese industrial economic development. While pointing out the direction for the sustainable development of Chinese industry, it is also effectively promoting the sustainable development of Chinese VFD (Variable-frequency Drive) industry. Make Chinese VFD (Variable-frequency Drive) industry continuously expand the market share of the industry, and rely on its strong development force to become an important basis for Chinese industrial economic development.

Frequency conversion energy saving is mainly used in occasions where it is necessary to change the speed of the AC motor and change the characteristics of the driving machinery to meet the requirements of the production process, and it is mostly used in fans and water pumps. When the motor can only run at the rated speed, its driving machinery can only run at a certain rated speed. When the production process requires adjustment of the process parameters, the flow rate can only be changed by increasing (decreasing) the system resistance, and the motor is always running under the rated condition, resulting in a waste of electric energy. Such as fans, pumps and other equipment, the traditional speed regulation method is to adjust the outlet (or inlet) baffle and valve opening to adjust the air supply and water supply. probability of system failure. When using frequency conversion speed regulation, if the flow requirement is reduced, the requirement can be met by reducing the pump or fan speed.

On the whole, VFD (Variable-frequency Drive) mainly achieves energy saving effect through power factor compensation and soft start. In terms of power factor compensation, since reactive power will increase line loss and heat generation of equipment, coupled with the reduction of power factor, the active power of the grid will decrease. Among the large reactive power consumption lines, the equipment use efficiency is low and the waste is serious. After using the frequency conversion speed control device, the VFD (Variable-frequency Drive) internal filter capacitor acts, thereby reducing reactive power loss and increasing the active power of the grid.

In terms of soft start and energy saving, the hard start of the motor will have a serious impact on the power grid, and at the same time, the requirements for the capacity of the power grid are too high. When a large current and vibration are generated during start-up, the damage to the baffle and valve will be great, and the use of equipment and pipelines will be greatly damaged. Life expectancy is extremely unfavorable. Using the soft start function of VFD (Variable-frequency Drive) will start the starting current from zero, reduce the impact on the power grid and the requirements for power supply capacity, prolong the service life of equipment and valves, and thus save equipment maintenance costs.

However, it should be noted that the problem of "small horses and large carts" should be avoided in the use of VFD (Variable-frequency Drive). The reason for this problem is based on the limitation of working conditions when the design was put into production at that time, so that in order to save money during design and installation, many places have adopted the setting that the frequency conversion power is less than the rated power of the motor. However, with the development of technology and changes in process and production conditions, the problem of "small horses and large carts" will inevitably appear, resulting in the failure of VFD (Variable-frequency Drive) to operate normally. Therefore, during the trial period of the frequency conversion device, in order to prevent problems before they happen, detection and adjustment should be carried out in advance to avoid the above problems. In addition, after 6 to 10 years of normal use, VFD (Variable-frequency Drive) tends to enter a period of high incidence of failures. Failures such as component burnout, failure, and frequent activation of protection functions often occur, seriously affecting its normal operation.

Fan frequency conversion speed regulation reduces cement power consumption

Industry reports pointed out that Chinese VFD (Variable-frequency Drive) market is currently in a period of rapid growth and is widely used in textile machinery, air conditioners, elevators, metallurgy and other industries. In the past few years, Chinese VFD (Variable-frequency Drive) market has maintained a high growth rate. According to estimates, according to the demand of the Chinese market, it will take at least 10 years for the market to become saturated and gradually mature. Therefore, Chinese VFD (Variable-frequency Drive) market has broad room for development.

At present, China is vigorously promoting the concept of energy conservation and environmental protection. After the 6% shrinkage of the subdivided market of the frequency conversion industry in 2012, it is gradually returning to growth. The investment of 4 trillion yuan in energy conservation and environmental protection has further stimulated the VFD (Variable-frequency Drive) industry market development of. Taking the cement industry as an example, in the mechanical and electrical equipment of the cement plant, centrifuges, water pumps, air compressors, powder separators, rotary kilns, ball mills, plate feeders, speed-regulating belt scales, coal feeding reamers, grate Frequency conversion speed regulators can be used on all equipment that requires AC speed regulation, such as refrigerators, shaft kiln Roots fans, unloaders, etc., to achieve the function of saving energy and reducing consumption. Among them, the frequency conversion speed regulation of fan adjustment is widely used in various industries at home and abroad as an energy-saving means. Foreign cement companies have widely used fan frequency conversion speed regulation to meet system adjustments in different working states to reduce power consumption costs. Exploring the energy-saving potential of fans has become a major measure to enhance the market competitiveness of cement enterprises.