400Hz variable frequency power supply speed control technology has been widely applied in industrially developed countries. In the United States, 60%-65% of the generated electricity is used for motor drives, and due to the effective utilization of variable frequency speed control technology, the industrial transmission electricity alone saves 15%-20% of the electricity. The adoption of variable frequency power supply speed control serves two purposes: speed regulation as required and energy saving. It primarily relies on the following factors:
(1) The variable frequency speed regulation system has low self-consumption and high work efficiency.
(2) The motor operates at a low slip rate, reducing rotor losses.
(3) Achieves soft start and braking functions, reducing the impact of starting current.
When using variable frequency power supply to control speed, various aspects such as process requirements, cost savings, and investment recovery period should be considered. If only process requirements and cost savings are taken into account, the following situations are more advantageous for choosing variable frequency speed control:
In accordance with process requirements, production lines or individual machines may need to adjust motor speeds programmatically or as specified. For instance, in the case of packaging machine conveyance systems, the system's conveyance speed must be altered based on different types of products. Variable frequency speed control can simplify the structure of the speed control system, ensure accurate control, and facilitate programmatic control.
Replacing mechanical speed regulation with variable frequency speed regulation. For example, in machine tools, this not only eliminates the complex gear transmission, but also improves accuracy and meets program control requirements.
Replacing gate or baffle flow adjustment with variable frequency speed control is suitable for fans, pumps, compressors, etc. For example, the water pumps, blowers, and induced draft fans on a boiler have implemented variable frequency speed control. This not only eliminates the need for servo amplifiers, electric operators, electric actuators, and water valves (or dampers), but also ensures the entire boiler control system achieves rapid dynamic response, high control accuracy, and stability.
