Description of the SF series

Overview of Frequency Inverters

The frequency inverters of this line are designed to convert single-phase or three-phase alternating current with a working frequency of 50 hertz into three-phase voltage with a controlled frequency. This process is crucial for all asynchronous motors, the rotor speed of which directly depends on the power supply frequency.

Principle of Frequency Control

The principle of frequency control is directly related to regulating the working frequency of the motor's voltage, which is achieved through the frequency inverter. This allows the operator to control the rotor speed of rotation, providing the ability to adjust the output frequency over a quite wide range—both increasing and decreasing it when necessary.

Quality and Reliability of Inverters

The frequency inverters of this line are distinguished by high quality and represent effective solutions for the operation of mechanized and automated systems, enhancing their productivity and reliability in controlling the frequency of electric motors, particularly asynchronous ones.

Shihlin Electric, established in 1955, guarantees the quality of its products through the use of cutting-edge technologies and developments. Its products are highly regarded by experts around the world and have received positive feedback from users in both domestic and international markets.

Areas of Application

Shihlin Electric frequency inverters are actively used in various industries, including:

• In pumping and ventilation systems, such as air conditioning, sewage, and circulation.
• For agricultural pumps.
• In lifting and transportation equipment, including belt conveyors, doors, escalators, winches, and cranes.
• For food, packaging, and filling equipment: mixers, blenders, and production lines.

Technical Specifications

• Inverter power ranges from 55 to 160 kW.
• Maximum torque values (1 min) are 110-130%.
• Equipped with a PID controller.
• Control modes: vector and scalar.

Advantages

• Automatic torque enhancement due to vector control.
• Slip compensation.
• Modes with reduced speed and increased torque.
• 32-bit CPU and sinusoidal PWM control, allowing for high-speed information processing.
• “Soft” PWM modulation for increased efficiency and reduced noise levels.
• Automatic system restart after stopping and smooth resumption of motor operation by setting its speed.