The frequency converter is a power control device that uses the on-off effect of power semiconductor devices to convert the power frequency power supply into another frequency. With the rapid development of modern power electronics technology and microelectronics technology, high-voltage and high-power variable frequency speed regulation devices continue to mature, and the high-voltage problem that has been difficult to solve has been well solved by device series or unit series connection in recent years.
High-voltage and high-power variable frequency speed control devices are widely used in various fans, pumps, compressors, rolling mills, etc. in large-scale mining production plants, petrochemical industry, municipal water supply, metallurgical steel, power energy and other industries.
Pump loads, which are widely used in metallurgy, chemical industry, electric power, municipal water supply and mining, account for about 40% of the energy consumption of the entire electrical equipment, and electricity costs even account for 50% of the cost of water production in waterworks. This is because: on the one hand, equipment is usually designed with a certain margin; On the other hand, due to changes in working conditions, the pump needs to output different flow rates. With the development of market economy and automation, the improvement of intelligence, the use of high-pressure frequency converter to speed control pump load, not only to improve the process, improve product quality is good, but also is the requirement of energy saving and equipment economic operation, is an inevitable trend of sustainable development. The benefits of speed control of pump loads are numerous. From the application examples, most of them have achieved good results (some save energy as much as 30%-40%), greatly reduce the cost of water production in the waterworks, improve the degree of automation, and are conducive to the pressure reduction operation of pumps and pipe networks, reduce leakage, burst pipes, and extend the service life of equipment.