FGI FD5000 Drive Application in Extruder Machines

Project Background

An extruder machine plays a key role in the plastic processing industry. It heats, shears, and pressurizes solid plastic materials. This process then shapes and continuously extrudes the plastic. Extruders are one of the most widely used machines in modern polymer production. The extruder's main motor speed directly affects both production efficiency and product quality. Therefore, upgrading the extruder with a variable frequency drive (VFD) is necessary.

Customer Needs

A foreign plastic processing plant decided to upgrade its new extruder equipment. The goal was to replace the old extruder's VFD from a well-known international brand. The customer required the new system to meet the following needs:

1. Operate without an encoder using open-loop control.

2. Deliver high torque at low frequencies.

3. Allow users to read drive data, such as current and voltage, and display system status.

Solution

To meet the customer's needs, FGI chose a one-drive-to-one-motor system with a manual switch function. The specific model is the FD5000-6/630F-1M.

FGI used sensorless vector control technology. This technology relies on an algorithm to monitor load speed and other parameters in real time. As a result, the system achieves excellent open-loop speed control. This control method provides high starting torque. It also helps avoid overcurrent faults caused by load fluctuations.

The VFD automatically records key operating parameters during operation. These include reference frequency, actual running frequency, output current, input current, input voltage, output voltage, actual pressure, and current time. The drive stores all recorded operating parameters as text files in the human-machine interface (HMI). It uses the date as the file name.

The system adopts a manual bypass design. Users can manually switch between VFD and direct grid operation. If the VFD fails, users can switch to grid operation manually to continue production. This design also allows maintenance on the VFD without stopping the production line temporarily.

Customer Benefits

Energy Efficient: The VFD delivers constant torque output. It saves more energy than other speed control methods, especially during low-speed operation.

Precise Control: The VFD includes automatic overcurrent and overvoltage detection. These features maximize equipment protection. The drive also responds quickly and adapts well to load changes, which ensures stable operation and high productivity.

Improved Quality: The VFD suppresses sudden current changes and automatically adjusts screw speed. This helps prevent quality issues in finished products, such as wire breaks or air bubbles.

Equipment Protection: The VFD's soft start function starts current from zero. It limits the current level during acceleration as set in the drive. This reduces the impact on the power grid and lowers grid capacity requirements. It also extends equipment life.