Plug-in Hybrid Three-Wheeler Fueled with LPG-Ethanol Dual Injection

The paper presents the concept of a plug-in hybrid three-wheeler converted from a conventional gasoline motorcycle Honda RSX 110cc. The powertrain of the three-wheeler includes an internal combustion engine (ICE) driving the rear wheels and an electric motor driving the front wheel. The ICE is fueled with LPG-ethanol dual port injection. A microcontroller is set up connecting with the ECM of the original ICE for flexible adjustment of the ethanol/LPG ratio based on the gasoline injector control signal. The results show that the LPG-ethanol dual port injection forms a stratified octane number distribution at the end of the compression process. The relatively LPG-rich zone is found around the spark plug while the ethanol-rich zone is located near the cylinder wall. With the same throttle opening, when engine speed increases, to keep the equivalence ratio and ethanol/LPG rate unchanged, fuel injection time must be reduced. The reduction of the LPG injection time is, on average, faster than that of the ethanol injection time. A control system is designed for smooth combining use of the two power sources of the hybrid three-wheeler. In full load condition, the vehicle can run at maximum speed of 36 km/h in electric motor operating mode and 70 km/h in ICE mode. The vehicle acceleration time from 0 to 32 km/h is 40s.