Numerous manufacturers of machines and plants have already transitioned from COMBIVERT F5 frequency inverters to F6 drive controllers. It’s also time to implement the change for the high-speed variants of the drives. The F6 High Speed Drives introduce a next generation of devices that, when paired with suitable filter technology, guarantees an outstanding price-performance ratio—optimized for applications like turboblowers, turbo compressors, spindles, or vacuum pumps. The transition is simpler than many might believe.
With the discontinuation of the COMBIVERT F5 inverters and the transfer of responsibility for the series to KEB Global Service, the need for a suitable successor for high-speed applications has emerged. This was already discovered and showcased to the public for the first time at last year’s SPS with the COMBIVERT F6 High Speed Drives. The new generation not only takes the place of its predecessor but also establishes new benchmarks in numerous ways.
“Our customers benefit from more compact dimensions and save valuable space in the control cabinet. The F6 High Speed Drives with 450 kW are more than 40 per cent smaller than previous models in this power class,” says Fabian Fischer, Team Leader Application Sales at KEB. “In addition, the switching frequencies can now be flexibly adjusted from 1.5 to 16 kHz in 1.5 kHz steps.” Another advantage of the drives is that a wide variety of motor technologies can be controlled. This means that induction, PM and IPM motors with and without encoders can be operated with just one software.
In future, the new High Speed Drives will ensure cost savings thanks to integrated safety functions such as safely limited speed (SLS) and maximum speed monitoring (SMS), which prevent overspeed and, as a result, damage to the machine. Another new feature is that the drives in the liquid-cooled version are designed for high input temperatures of up to 55 degrees Celsius and the circuit boards are optionally available with a 3C3 protective coating (IEC/EN 60721-3-3 Class 3C2). This provides the best conditions for use in the harsh environmental conditions in which high-speed applications often operate.
How to change the drive easily
The sixth generation of drives in the high-speed version is designed for outputs from 30 to 450 kW and output frequencies up to 2,000 Hz and is currently available in four housing sizes. The COMBILINE Z2 sine wave filters, which consist of a motor choke and a capacitor, are available to match the F6 High Speed Drives. Thanks to a modular principle, these can be customised and create a high degree of freedom. Users benefit from an efficiency of more than 99.9 per cent and a significant reduction in harmonic losses in the motor.
Plant and machine manufacturers who would like to switch from F5 to F6 High Speed can get in touch with their contact at KEB. The service team will support users with any questions regarding the changeover. Especially practical: the new drives can be designed using Hardware in the Loop (HIL), among other things. “HIL enables real-time simulation of the hardware for a realistic virtual representation of complex systems. The known motor, sine filter and inverter data are sufficient to carry out a virtual commissioning of the entire system without the presence of the real components – this saves time and money,” says Fischer.
The Matlab simulation software provides further assistance when switching from F5 to F6 High Speed. It can be used to make predictions about the static and temporal progression of the speed, voltage or current based on known motor data. Matlab identifies resonance points in the electrical system that are required for the optimum dimensioning of perfectly matched components for high-speed applications.