Frequency Control of Electric Motors
Modern technological systems are inextricably linked to the use of alternating current electric motors, which convert electrical energy into mechanical energy. They ensure the operation of various mechanisms, performing tasks in different areas of industry. In recent years, frequency control has gained the most popularity, which is carried out using a frequency converter. This device provides the supply of voltage to the motor with a regulated frequency and amplitude, which, in turn, allows controlling the speed of the motor and the torque on its shaft.
Advantages of Frequency Controlled Drives
The implementation of frequency control provides the following advantages:
- reduction of electricity consumption by 30-50%;
prolonged service life of motors and other drive elements; - automation of control and management of operating modes;
- reduction of the load on the electrical network.
Due to these advantages, frequency-controlled drives (FCDs) are widely used in technological systems where it is necessary to:
- implement smooth or stepwise regulation of angular velocity;
- ensure stability of speed or torque;
- ensure coordinated operation of several drives;
- automate technological processes;
- reduce energy resource consumption.
Adaptation of Electric Motors for FCDs
To achieve maximum efficiency and reliability of FCD operation, it is crucial to ensure coordinated operation of the frequency converter and the electric motor. Modern converters allow for automatic detection and adjustment of key system parameters. However, the adaptation of alternating current motors may still be necessary to achieve optimal characteristics.
Thanks to this adaptation, electric drives can meet domestic and international standards, allowing them to pass certification. Many systems require compliance with protection standards IP 54 and climatic requirements U3. In some cases, it is necessary to use motors with enhanced protection (IP 55) or with special climatic characteristics (U2, UHL1, U1). In such situations, the modernization of the electric motor is mandatory.