HST Integral™ aeration compressor automatically self regulates to operate at best efficiency. Designed to maintain reliability and efficiency within 1-2% of the best efficiency point, high speed turbocompressor with frequency converter and magnetic bearings has been engineered to work within the most demanding and variable wastewater and industrial process applications. Compressor automatically senses and compensates for the surge condition and maintains a steady aeration flow. Maintenance-free compressor features non-contacting rotating parts, no inlet guide veins and no outlet diffusers. HST design provides oil-free air to an aeration system that helps prevent plugging the diffusers and will not reduce or otherwise affect the oxygen transfer rates. Without oil and filter changes or seals to maintain, repair, or replace, there is no maintenance required.