Abstract: A method of controlling a motive power and fluid driving system according to the present invention is disclosed, which generally comprises the steps of sensing a plurality of operating parameters and at least one control parameter defining the energy quotient for the motive power and fluid driving system, and adjusting the control parameter(s) to substantially maximize the energy quotient for the system. The control method may also include the step of substantially maximizing the energy quotient at a predetermined or desired capacity of fluid flow.

Abstract: A method and system for controlling natural gas compressor and engine units. Particularly, the control method provides for the adjustment of the engine speed and compressor loading, so as to minimize the compressing energy required while maintaining a desired gas flow through the pipeline. The control of the engine speed and compressor loading is based in part on an energy quotient value for the unit. The control method further provides for efficient operation during multiple-stage compression, by controlling the interstage pressure. The control method is also adapted to predict impending compressor and engine unit failures. The control system is based upon a digital-type controller which generates control signals in response to changes in the energy quotient value for the unit.