Abstract
Keywords
Load Detection, Ambient Pressure Estimate, Anti Reverse, Stroke Detection
Abstract
Engine management systems (EMS) for small engines require some specific solutions that are different from EMS for automotive engines. The specific requirements are due to special behavior of these engines on one hand, and the need for cost saving by reduction of the number of components on the other hand. Some special functions for small engines are introduced: engine load detection for P-n system, ambient pressure detection, stroke detection and anti reverse rotation function. In single cylinder engines, the intake air pressure and engine speed signal fluctuate periodically. At first, the special behavior of these two signals is investigated for different working conditions. Then functions for load detection and ambient pressure estimation are designed based on intake air pressure signal, and functions for stroke detection and anti-reverse are developed on the basis of engine speed detection. Test results show that these functions work well.