Review of Methods for Energy Harvesting from a Vehicle Suspension System

With the increasing population the energy consumption has increased which makes the requirement for clean energy important, now more than ever. The transport sector is one of the biggest contributors to this consumption and should therefore be taken into consideration when looking for environmentally friendly solutions. The majority of fuel energy in road-bound vehicles of today is dissipated and is therefore never utilized. For a passenger car traveling at 13.4 m/s it is found that 200 W worth of energy is lost in the vehicles suspension system. The purpose of this work is to analyze and evaluate existing methods for energy regeneration from vehicle suspension systems in order to identify the most optimal solution. To end with, the report will propose mathematical models for simulations of the chosen system. This report examines electrostatic, piezoelectric and electromagnetic methods of energy regenera- tion and it is concluded that electromagnetic generators are the most viable when applied to vehicles. Furthermore, already existing ideas for regenerative suspension systems using electromagnetic generators are explained and compared. It is concluded that a suspension system using an electromagnetic generator coupled with a magneto-rheological (MR) damper is the most optimal when looking at e-ciency, cost, robustness and environmental impact. It can generate up to 90 W and is shown to be the most robust system because of its few moving parts. The working principle of the regenerative electromagnetic MR damper is explained and mathematical models describing the characteristics of the MR damper and the electromagnetic generator, based on previous work, are proposed. A simulation model using a quarter-car model is also proposed where dierent methods of road prole generation are suggested. The environmental aspects of the regenerative MR damper is conclusively discussed and evaluated so that the overall environmental performance of the system can be decided