Optimized Design of a Wireless Charger Prototype for an e-Scooter

Abstract

Individual mobility vehicles are revolutionizing transportation in the urban environment. Among them, e-scooters are one of the fastest growing vehicles. However, these vehicles have some drawbacks such as incompatibility among different chargers or reduced autonomy, which especially affects e-scooters rental. Wireless charging is presented as a solution to these drawbacks since it allows the batteries to be charged without user intervention. This paper addresses the design process and implementation details related to a magnetic-resonance charger for an e-scooter. In contrast to the previous works, we present a comprehensive approach that addresses the design of the coil topology, the dimensions of the ferrite tiles, the definition of the gap and the optimised control for a CC-CV charge. The main contribution of the work is the consideration of all these issues jointly while we also take into account the vehicle's materials and structure for an accurate design and implementation. The dimensions of the vehicle impose a strong restriction on the coil design. Therefore, a detailed analysis about the location of the secondary and primary coils in a real e-scooter is executed with Ansys Maxwell. The study about the geometries of ferrite tiles is also performed considering the particularities of this type of vehicle. This study led to an optimal solution for the coil geometries and ferrite placement that minimizes the costs. The proposed system has been validated with the implementation of a real prototype of 100 W, to which a CC-CV control has been incorporated to achieve a safe charge for different battery states. The control can be easily adapted for a wide range of e-scooters. In this way, the use of this type of chargers on public installations can be maximized.

Software implementation of methods for optimal design of power electronic devices

“…The task is solved in the MATLAB environment, and for this purpose an author's program (m-file) is compiled. The program includes: the objective function ( 2), equality type constraints -differential equations ( 1) and inequality type constraints (3). The optimization itself is done with the command val=fmincon(@OptFun,100e- between points of the wrap of and the etalon of this wrap are included in parentheses.…”

“…Power electronic devices are a major tool in the transition to a carbon neutral society. In this sense, the problems related to their analysis, design, modeling and prototyping are key to the realization of the energy policy of modern countries [1][2][3]. This determines the huge interest in applying different methods and approaches for their design and operation.…”

Magnetic Integration of Circular Pads and LCC-LCC for EV Wireless Charging Tolerant to Misalignment

“…Few articles use the circular pad, which is simple but it offers an acceptable performance [6]. Circular coils can be found in e-scooters [21], personal mobility devices [22], drones [23], [24] or ebikes [25]. The effect of misalignment on the power transfer and on the magnetic integration is a common topic discussed in the related work but the effect of both the magnetic integration and misalignment on the efficiency is a topic only studied in [15]- [18], [20] .…”