Study on starting characteristics of free-piston gasoline engine for linear alternator

In order to obtain starting process characteristics of a spark ignited free-piston linear alternator, a starting process simulation model based on coupling the alternator dynamics and thermodynamics equations was established to analyze theoretically energy transference and conversion relationship in starting process. By using the model and actual test way, two typical starting methods were investigated. Results indicate that both start modes of constant acceleration and constant thrust can realize the alternator starting burning; the former is beneficial to the first time compression starting combustion, and the latter beneficial to the opposite cylinder starting combustion. It is revealed that in starting process, gas leakage loss is more than friction loss fraction, that should not be ignored in design.