50Hz 60Hz Flux Vector VFD Three Phase Variable Frequency Drive High Precision

Working Principle

• Rectification process: The frequency converter first converts the input AC power (usually 50Hz or 60Hz power frequency) into DC power through a rectifier. This process utilizes the unidirectional conductivity of rectifier diodes.
• Filtering process: The rectified DC power may contain pulsating components, so it needs to be smoothed through a filtering circuit to remove the pulsation in the power supply and obtain a stable DC power supply.
• Inverter stage: The filtered DC power is then converted into AC power with adjustable frequency and voltage through an inverter. The inverter is mainly composed of IGBT (Insulated Gate Bipolar Transistor), which can achieve precise control of the output power frequency and voltage by controlling the switching state of IGBT.
• Control circuit: The control circuit is the core part of the frequency converter, including the main control circuit, signal detection circuit, drive circuit, external interface circuit, and protection circuit. It is responsible for receiving external instructions, detecting the operating status of the motor, and outputting control signals to the inverter based on this information to achieve precise control of the motor.

FEATURES

• Vector control technology: Vector control technology is an advanced motor control method that can decompose the stator current of the motor into two components: excitation current and torque current, and control them separately. This technology can achieve high-precision speed regulation and fast response of motors.
• Direct Torque Control (DTC): DTC technology directly analyzes the mathematical model of an AC motor in the stator coordinate system, while controlling the motor's magnetic flux and torque. It abandons the complex calculations in vector control and has faster response speed and higher control accuracy.
• Matrix AC-AC frequency conversion: Matrix AC-AC frequency conversion technology eliminates the intermediate DC link and directly converts AC power to AC power through frequency conversion. It has the advantages of a power factor of 1, a sine input current, and the ability to operate in four quadrants.

Application

Frequency converters are widely used in various industries such as power, public works, textiles and chemical fibers, building materials, petroleum, chemical, food and beverage, tobacco, coal, and mechanical processing. In these industries, frequency converters play an important role in energy-saving speed regulation, torque control, position control, etc., providing strong support for the production efficiency and energy utilization efficiency of enterprises.