Development of 2-cylinder Diesel Engine for European quadricycles to achieve EURO 5+ standard

The EURO 5+ standard (134/2014/EU) has been enforced in the year 2025 for quadricycle in Europe. The exhaust emission under this standard has significantly tightened compared to the EURO4. Additionally, this standard also limits vehicle weight, which remains stringent and unchanged from the EURO4 standard. We introduce the original technologies to meet EURO5+ standard in this paper. Emission limit values of the EURO 5+ standard are more stringent, requiring an 84% reduction in NOx and a 94% reduction in PM compared to the previous standard. Diesel engines equipped with mechanical injection control systems for the previous standard are required significant technological advancements to meet EURO 5+ standard of exhaust emission. To meet this, the adoption of engine aftertreatment components such as SCR(Selective Catalytic Reduction) for NOx reduction and DPF(Diesel Particulate Filter) for PM reduction is an common solution. However, to meet this new regulation, adding the weight of these after-treatment parts would cause the vehicle to exceed the weight limit. Therefore, we have improved our original IDI technology to develop an optimal electronically controlled fuel injection system for small diesel engines, thereby improving the exhaust emission. By combining the flexibility of this electronic control system with the EGR(Exhaust Gas Recirculation) system, DOC (Diesel Oxidation Catalyst) and control programs for NOx and PM reduction, we have developed the engine that meets the Euro 5+ standard. This engine with these compact additional emission control devices also meet the weight limit. This paper will focus on introducing combustion improvement technologies that achieve low emissions with IDI combustion to comply with EURO 5+ standards, as well as technologies for compact additional emission control devices aimed at achieving low emissions that meet the requirements of targeted European quadricycles.