To improve vehicle performance and energy utilization, a novel planetary gear set based flywheel hybrid electric powertrain (PGS-FHEP) is proposed. The PGS-FHEP involves an internal combustion engine, a planetary gear set that integrated a control motor and an energy storage flywheel, which combines the high efficiency of the mechanical flywheel energy storage system with the flexible and controllable characteristics of the electric motor. The powertrain is analyzed and modeled using lever analogy method, and a rule-based control strategy is designed and verified under different test cycles. The simulation results indicate that compared with the traditional manual transmission vehicle, the fuel economy of the vehicle equipped with PGS-FHEP can be improved by more than 50%, and the acceleration performance can be increased by 28.01%. Up to 60.61% of vehicle kinetic energy can be recovered by PGS-FHEP, among which 37.85% can be directly captured by the energy storage flywheel. In addition, the battery charging power is reduced, which is beneficial to prolong the battery life.
The introduction of fuel economy and CO 2 emission legislations for passenger cars in many countries and regions has spurred the research and development of more efficient gasoline engines. The pumping loss at part-load operations is a major factor for the higher fuel consumption of spark-ignition gasoline engines than the diesel engines. Various approaches have been identified to reduce the pumping loss at part-load operations, leading to improved fuel economy, including early intake-valve closing, positive valve overlap and controlled auto-ignition combustion. On the other hand, in order to reduce the CO 2 emissions from the fossil fuel, ethanol produced from renewable resources is becoming widely used in the gasoline engine. In this article, the performance, combustion and emissions were measured, analysed and compared between gasoline and its mixture with ethanol (E15 and E85) at a typical part-load condition when a direct-injection gasoline engine was operated with the controlled auto-ignition combustion by means of the negative valve overlap and spark-ignition combustion by means of the intake throttled, early intake-valve closing and positive valve overlap. An electro-hydraulic actuated camless system enabled the engine to be operated with controlled auto-ignition combustion and spark-ignition combustion of different valve timings and durations at the same load. The results showed that the controlled auto-ignition combustion reduces nitrogen oxide emissions by more than 90%. The positive valve overlap results in better mixture preparations and improved combustion efficiency and best fuel economy compared to all the other modes. The early intake-valve closing operation led to a moderate improvement in the fuel conversion efficiency over the throttled spark-ignition operation, but it was characterised by the slowest combustion and worst hydrocarbon and carbon monoxide emissions. Fewer and smaller particle numbers were detected in early intake-valve closing using E0 and E15 fuel blends. Using ethanol blends reduces the knocking combustion in controlled auto-ignition modes by about 50%. The use of E85 resulted in an increased number of particulate emissions in early intake-valve closing but increased indicated specific fuel consumption in all the modes. The particulate emission results showed that soot is the dominant particle in the exhaust.
In recent years, green communication has been studied as a promising technology to conserve energy consumption, reduce radio emission and ensure sustainable development of wireless communication systems. A green mobile network will be integrated with the state-of-art advanced wireless networking technologies to fulfill end-to-end green communications. Cooperative communication has been widely utilized to significantly improve system performance and decrease power consumption. In this paper, we utilize cooperative relay to conserve energy consumption in green mobile networks. The relay selection and power allocation are investigated. The theoretical analysis is carried out under different number of cooperative users. We derive the explicit expression of energy consumption for the Amplify-and-Forward (AF) protocol with multiuser diversity. Simulation results demonstrate that the proposed relay selection and power allocation schemes significantly reduce energy consumption in green mobile networks.
Double Rotor Motor Power Coupling System (DRM-PCS), as a new kind of power coupling system, can be used in hybrid electric vehicle to make the engine operate efficiently by decoupling the engine speed from the wheels.In this paper, the thought and method of the engine optimal control are put forward.With the help of the data fitting method and the steepest descent algorithm, the optimal operation point of the engine is calculated.Then using the fuzzy control method, the simulation model of the engine optimal operation point controller is established.The simulation results show the controller can make the effective adjustments to the engine operation, and the control performance on the engine fuel consumption rate is better.In addition, the simulation results suggest that the optimization time of the control method has obvious influence on the stability of the DRM-PCS in the hybrid driving mode with low speed.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)
'%3e%3cpath fill='%23012169' d='M0 0v30h60V0z'/%3e%3cpath stroke='%23fff' stroke-width='6' d='m0 0 60 30m0-30L0 30'/%3e%3cpath stroke='%23C8102E' stroke-width='4' d='m0 0 60 30m0-30L0 30' clip-path='url(%23b)'/%3e%3cpath stroke='%23fff' stroke-width='10' d='M30 0v30M0 15h60'/%3e%3cpath stroke='%23C8102E' stroke-width='6' d='M30 0v30M0 15h60'/%3e%3c/g%3e%3c/svg%3e)