A Purely Mechanical Energy Storing Concept for Hybrid Vehicles
The paper contains the design and simulation of a purely mechanical system for storing energy during vehicle deceleration, which can be utilized during subsequent acceleration (regenerative braking). A continuously variable transmission (CVT) regulates the energy transfer, energy storage is accomplished by means of a spiral spring and additional use of a planetary transmission. The transmission ratio of the CVT is adapted by a combined feed-forward and feed-back control. A computer simulation for a vehicle with an overall mass of 1500kg, and an energy storage capacity of 30kJ was performed for different driving cycles. In a typical urban stop and go situation the proposed device will save up to 0.72kg fuel per 100km and the overall efficiency analysis together with simple design, easy recycling, and long life expectance, showed a clear advantage over other hybrid concepts for frequent stops and accelerations.
Development and performance evaluation of a comprehensive automotive energy recovery system with a refined energy management strategy
Abstract The development of automotive energy recovery technologies which mainly include the recovery of braking, vibration and exhaust energy have been highly promoted due to pressing energy issues. Nonetheless, the comprehensive study of energy recovery technologies applied simultaneously to a vehicle rarely receives attention. The recovered energy introduces further complications for the power sources system, which drives the refinement of the existing energy management strategy. This paper presents a novel comprehensive automotive energy recovery system. Energy conversion mechanism and energy saving potential are thoroughly explored based on the developed comprehensive energy recovery models. Bench tests are conducted to demonstrate the energy recovery performance and the effectiveness of the proposed scheme. Based on the analysis of energy flow, a novel assistant power balance strategy is developed to ensure the fair use and storage of the recovered energy and increase the energy conversion efficiency. Comparative analyses in typical cycles with various road disturbance are carried out to validate the effect of developed energy management method. The results indicate that profit of proposed strategy increases with the amount of the recovered energy and fuel economy can be well improved.
Frequency selective surface design for blinds applications
In this paper, the reconfigurable blind structure with frequency selective surfaces(FSS) for the building applications are presented. Frequency transmission characteristics for different angles of the proposed blind-FSSs are investigated and verified through simulation and measurement. The simulation results show that we can implement the reconfigurable blind-FSS for multiband wireless applications. To verify the proposed paper, two kinds of blind-FSSs, crossed dipole FSS and circular ring FSS are fabricated and measurements are performed for different angles. The proposed structure in this paper which is very simple, can be easily applied to any planar surface for wireless security applications at low cost.