The Technology

Diffuser Control - Mechanical 1-Point Control

This control mechanism is a 1-point control, regulating the airflow with mechanical outlet diffuser vanes ,changing the relative airflow vector and therefore relative air- speed with limited influence to the required pressure line. Effectively moving the compressor performance curve along the horizontal axis. No efficiency compensations for fluctuations in pressure and air characteristics (temperature, relative humidity) are provided. To add this control feature, refer to the 2-point-control mechanism below.

Diffuser and VFD Control - Electrical 2-point-Control

Featuring the mechanical outlet diffuser blades, but extending the control range with its electrical 2-point control. A standard low frequency VFD is adjusting the speed within a limited bandwidth to adjust the compressor operation to pressure/ air quality fluctuations (e.g. temperature, relative humidity). Please note: the VFD is not used, as in regular 1-point speed controls, to regulate the airflow; it is a fine-tunding mechanism. The airflow regulation is handled by the outlet diffuser vane system.

Diffuser and Inlet vanes Control - Mechanical 2-point-Control

Featuring the same 2-point mechanism as above, but utilizing two mechanical systems: the outlet diffuser vanes in combination with inlet guide vanes. The inlet guide system also adjusts for changes in pressure and air quality (e.g. temperature, relative humidity) by changing the pre-rotational angle of the inlet air flow. This is handled with contant speed. Compare the relative efficiency map to the right to see the differences.

Diagrams: The dark blue lines represent relative efficiency lines; dashed black lines are the compressor curves as different diffuser positions.