17. March 2021

Turbo compressors for operation at high-altitude

How nice it would be to drive a fuel cell vehicle through the mountains and over a pass emission-free and to enjoy the scenery? This is now possible with Celeroton’s CT-2X series of turbo compressors with gas bearings!

The absolute air pressure at the inlet of the compressor is the relevant reference value for the operability of turbo compressors with gas bearings. The air pressure at the inlet corresponds approximately to the ambient pressure if the intake system with air filter and tubing is designed accordingly, and then decreases with increasing altitude. Low ambient pressure levels are challenging conditions for the gas bearing. The pressure forces at higher ambient pressure levels and thus operation of the compressor at sea level usually have a stabilising effect on the gas bearing and at the same time increase load-bearing capacity. As a consequence, a special gas bearing design is necessary for low ambient pressures, as well as special consideration of the resulting load capacity with regard to the vibration resistance of the compressor (see also article regarding vibration testing).

From the user’s point of view, information about the operating altitude is usually easier to understand. The basic relationship between air pressure and altitude is often described with the barometric altitude formula. However, it does not take into account effects such as the influence of the weather.

Turbo compressor in front of Swiss alpine pass
Celeroton Turbo Kompressor CT-25-10000

Celeroton CT-2X series compressors, such as the CT-25-10000 with the CC-550-7500 inverter, are operable up to an absolute compressor inlet pressure of 0.7 bar, which is equivalent to about 3000 m according to the barometric altitude formula. Tests have confirmed that these demanding conditions for the gas bearing can be covered with the Celeroton gas bearing technology. Thus, the Celeroton turbo compressors also enable rapid acceleration of the electric vehicle at higher altitudes, along with all the other advantages of a fuel cell drivetrain.