Optimal Design of a Novel Single-Phase 8-Slot 8-Pole Tubular Electromagnetic Shock Absorber to Harvest Energy

Abstract

Based on the dimensions and thresholds of power and power density of a commercial shock absorber in the Korando car (an SUV branch), a single-phase 8-slot 8-pole tubular permanent magnet (PM) machine was designed and fabricated. The main focus of this paper is on the increase of output power in a given space and reduction of the volume. This is successfully solved using a novel structure for PM and considering a number of slot-pole combinations. Furthermore, a multiobjective optimization is performed to find the tradeoff between various objectives. The experimental results reveal that the proposed machine can possibly regenerate a maximum of 339.95 W and an average of 96.67 W in terms of its output power. Considering the active volume, which includes PM, iron core, pure copper, and an electromagnetic air gap, the estimated maximum and average power density are 0.311 and 0.087 W/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> , respectively. Despite these satisfactory results, one of the major drawbacks to exploiting this machine is its high electromagnetic force, which causes negative effects on safety and driving comfort. With the aim to commercialize the proposed device, further work will be concentrated on the reduction of electromagnetic force and on performance of the road tests.