Development of an Electronic Integrated Throttle Body Governor for Fuel Injected Medium HP Integral Engine-Compressors
Reliable use of proven electronic governors on wellhead and gathering compressors is compromised by instruments and devices needed to convert the electronic control signal to a mechanical throttle. Instrument gas quality is difficult to maintain and normal machinery vibration aggravates small, close tolerance instruments. A simple butterfly valve throttle with an attached computerized servo used by small industrial engine generators was modified for use with pressurized natural gas. Control parameters and limits were evaluated and refined for application on one, two, three and four cylinder two-stroke cycle engines ranging from 200 hp to 880 hp. Transient response measurements were made in the R&D lab to compare the conventional governor arrangement to the servo controlled throttle body. Operational and reliability testing was performed at four field locations with a variety of compressor loading and rpm set point methods. Production use is anticipated pending the servo manufacturer's attainment of third party certification for use in Class I, Group D, Division 2 hazardous areas.