Development and Field Evaluation of Electronic Controls for Two-Cycle Engines (Case Study)
The gas compression industry is increasingly affected by several trends which require improvements in the degree of control of engine operating parameters. These trends include the continuing reduction of exhaust emissions, improvements in fuel economy, and the need for more comprehensive diagnostics. Electronic control systems can provide these advantages in a cost-effective manner. The application of electronic controls to an engine product line requires a thorough development program. In addition to evaluating the effects of the new controls on the engine performance, it is imperative to assure that the controls will provide reliable, long term operating characteristics. This paper describes the development and field evaluation required to apply electronic controls to a line of two cycle, integral, natural gas engines which have a long history in the gas compression industry. The electronic control system for these engines replaces a mechanical/hydraulic system. The new system incorporates three main engine functions: governing, ignition, and fuel injection. A primary focus of this report is on the four-step process used to qualify the control system for use with new production engines. This process consists of design, research testing, field prototype evaluation, and production implementation. Test results are reported, which include improvements in the long term control of emissions, reduced fuel consumption, maintenance of the load balance between cylinders, and diagnostic capabilities.