Variable frequency inverter, is the application of frequency conversion technology and micro-electronic technology, by changing the motor working power frequency mode to control the AC motor power control equipment.
Drive is mainly composed of rectifier (AC to DC), filter, inverter (DC to AC), brake unit, drive unit, detection unit and micro-processing unit, which depends on the on-and-off of internal IGBT to adjust the voltage and frequency of the output power supply, according to the actual needs of the motor to provide the required power supply voltage, so as to achieve the purpose of energy saving, speed regulation. In addition, it also has a lot of protection functions, such as over current, over voltage, overload and so on. With the continuous improvement of industrial automation, drives has been widely used.
Functions
Energy Saving
Energy saving is mainly manifested in the application of fan and water pump. While the fan, or pump type load adopts frequency conversion speed regulation, power saving rate will be 20% ~ 60%, this is because the actual power consumption of fan, pump type load is basically proportional to the third square of speed. When the average flow required by users is small, fans and pumps will use frequency control to reduce their speed, so energy saving effect is very obvious. But the traditional fan and pump uses baffle and valve to adjust the flow, so the motor speed is basically unchanged as well as the power consumption. According to statistics, fan and pump type motor power consumption is of 31% of the country's power consumption, industrial power consumption is of 50%. It is very important to use variable frequency speed-regulating device on this kind of load. At present, the successful application involves constant pressure water supply, all kinds of fans, central air conditioning and hydraulic pump frequency control.
Application in automatic system
Due to the built-in 32-bit or 16-bit microprocessor, with a variety of arithmetic logic operation and intelligent control functions, the output frequency accuracy of 0.1%~0.01%, and set up a perfect detection, protection links, therefore, our products are widely used in the automation system. For example: the winding, stretching, metering, and conducting wire in chemical fiber industry; the plate glass annealing furnace, glass kiln stirring, drawing machine, bottle making machine in glass industry; electric arc furnace automatic feeding, batching system and intelligent control of elevator.
Application in improving process level and product quality
Variable Frequency Drive(VFD)can also be widely used in transmission, lifting, extrusion and machine tools and other mechanical equipment control fields, it can improve the process level and product quality, reduce the impact and noise of equipment, prolong the service life of equipment. After using VFD to control the speed, the mechanical system is simplified, operation and control is more convenient, and some can even change the original process specifications, so as to improve the function of the whole equipment. For example, setting machines for textile and many industries, the temperature is regulated by changing the amount of hot air into the machine. The transmission of hot air is usually used by circulating fan. Because the fan speed is unchanged, the number of hot air is only adjusted by the damper. If there is throttle regulation failure or improper regulation, it will cause the setting machine out of control, thus affecting the quality of finished products. The circulating fan starts at high speed, and the wear between the belt and the bearing is very severe, making the belt become a consumable product. After adopting frequency conversion, temperature regulation can be realized by automatically adjusting the fan speed by VFD, which solves the problem of product quality. In addition, the VFD can easily realize the start of the fan at low frequency and low speed and reduce the wear between the belt and the bearing, but also prolong the service life of the equipment, and can save 40% energy.
Realize motor soft start
Hard start of motor will not only cause serious impact on the power grid, but also require too high capacity of it. The high current and vibration generated during startup can cause great damage to the baffle and valve, and will be extremely detrimental to the service life of equipment and pipelines. After using VFD, the soft start function of it will make the starting current change from zero, the maximum value does not exceed the rated current, reduce the impact on the power grid and the requirements of power supply capacity, not only prolong the service life of equipment and valve, but also save the maintenance cost of equipment.
