Evaluation of Fuel Economy and Emissions Reduction for a Motorcycle With Automatic Idling-Stop Device

Abstract

In an attempt to improve the fuel economy and reduce the exhaust emissions of motorcycles, some manufactures have developed commercialized motorcycles equipped with automatic idling-stop and go (AISG) functionality. Even though research efforts devoted to the idling-stop strategy have demonstrated its effectiveness, motorcycles equipped with the AISG device are not popular because the general public still has some concerns about them. This paper aims to evaluate the benefits and feasibility of a commercialized motorcycle with AISG functionality with regard to the public's concerns about fuel economy and emission problems during engine restart transients. In order to verify the accuracy of the analytical results and control for variable driver characteristics, a motorcycle chassis dynamometer was used to recreate the urban driving pattern. Furthermore, the feasibility of fuel-saving and emissions improvement by adjusting fuel-injection signal of the engine control unit (ECU) during engine restart operation was also evaluated. The experimental results showed that the addition of the fuel-injection modulation plus idling-stop strategy can improve the fuel economy rate by up to 12.2% and reduce carbon monoxide (CO) emission by up to 36.95% in comparison with the non-idling stop case.

Comparison between Hybrid and Fuel Injection Motorbikes

“…Considering these results, we can assume that hybrid motorbikes will also have the same difference in carbon emission from fuel injection motorbikes. As bike's size and weight is lesser than cars, and it usually ranges between 70-300 CC, the carbon emission will surely decrease by a larger factor [26].…”

An Innovative Constant Voltage Control Method of PMSM-Type ISG Under Wide Engine Speed Range for Scooter With Idling Stop

“…Hence, the generated power of the ISG is controlled by θ * v according to (4) to fulfil a constant dc-link voltage control over wide engine speeds. (ii) Voltage controller G c (s) is adopted to both stabilize dc-link voltage and reduce the effects of electric parameters variations caused by flux saturation and/or operating temperature change.…”

“…From which, the voltage controller G c (s) can be easily adjusting to achieve better dc-link voltage control in steady state. Actually, θ b and θ f are obtained from (4), except that θ b is set as 2 • to provide stable minimal power, which can avoid reading small but noisy dc-link current.…”

“…The technology can help by reducing vehicle fuel consumption up to 10% in urban test mode [1], [2] and up to 7% for scooters using the ECE R40 mode [3]. Moreover, the evaluated results in [4] show that idling-stop devices of motorcycles can reduce carbon monoxide emissions up to 36.9%. Additionally, an idling-stop system may use the existing 12V lead-acid battery or a low capacity Li-ion battery can be installed in other hybrid electric vehicles to fulfil…”