INTELLIGENT PORTABLE BATTERY CHARGER FOR E-BIKES: ONLINE OPTIMIZATION OF THE BATTERY CHARGING EFFICIENCY

最近，电动自行车已经很受欢迎，因为它们提供了几个好处，如方便骑手和不二氧化碳排放到我们的环境。然而，成本高和电池组使用时间短似乎是阻碍电动自行车在市场上广泛推广的最大缺点。为了降低成本，我们的工业合作伙伴Alizeti成功地开发了一种解决方案，将大多数现有的自行车转化为全功能的电动自行车。在这个解决方案中，动力系统基本上是基于一个与轮胎接触的电动滚筒，通过摩擦驱动自行车。电池和传动系统内置在一个紧凑的外壳上，固定在传统的后行李架上。由于这种简单的配置，骑行者可以很容易地将他们的自行车以低成本转换成全功能的电动自行车。为了提高电池组的使用寿命，本项目将完成智能便携式电池充电器的开发。Alizeti的电动自行车的电池组是由锂离子电池制成的24V/11.6Ah电池组。所开发的智能便携式充电器将具有两个主要优点。首先，在充电过程中使电池组阻抗保持在最小值，从而显著提高充电效率和电池寿命。这将为乘客带来经济效益，他们将不必支付频繁更换和维护电池组的费用。第二个特点是电池组可以使用交流和直流电源充电，电压范围大，直流供电时从12V到48V，交流供电时从95Vrms到265Vrms。有了这个功能，开发的充电器可以用所有流行的电源为电动自行车电池充电。因此，骑自行车的人会更有效、更舒适地使用他们的自行车。此外，这款开发的充电器的大小和重量与流行的上网本充电器相似。有了这些优点，电动自行车可以用智能的方式轻松充电。因此，该项目的完成将为电动自行车在道路上的广泛推广做出重大贡献，为用户提供一种低成本但功能强大的电动自行车。

Recently, e-bikes have been popular because they offer several benefits such as the convenience for riders andno carbon dioxide emission to our environment. However, the high cost and the short duration of battery packseem to be the biggest drawbacks that prevent e-bikes from widely spreading on the market. In order to reducethe cost, Alizeti, our industrial partner, has successfully developed a solution to convert most existing bicyclesinto a full featured e-bikes. In this solution, the powertrain system is basically based on an electric-poweredroller in contact with the tire which drives the bike by friction. The battery and the drive train are built into acompact enclosure to be fixed on a conventional rear luggage rack. Thanks to this simple configuration, theriders can easily convert their bike into a full featured e-bike at low cost. In order to improve the lifetime of thebattery pack, this project will complete the development of an intelligent portable battery charger. The batterypack of Alizeti's e-bike is a 24V/11.6Ah pack made from Li-Ion battery cells. The developed intelligentportable charger will perform with two main advantageous features. Firstly, the impedance of the battery packwill be maintained at its minimum value during the charging process in order to improve significantly thecharging efficiency and the lifetime of the battery. This will result in economy for the riders who will not haveto pay for frequent battery pack replacement and maintenance. The second feature is that the battery pack canbe charged from both AC and DC power sources with a large voltage range, going from 12V to 48V in case ofDC power supply and from 95Vrms to 265Vrms in case of AC power supply. With this feature, the developedcharger can charge the e-bike battery from all popular available power sources. As a result riders will use theire-bikes more effectively and comfortably. In addition, the developed charger has a size and weight similar tothe popular netbook chargers. With these advantageous features, e-bikes can be charged easily with anintelligent manner. Hence, the completion of this project will significantly contribute to widely spread thee-bike on the road by offering users a low-cost but powerful e-bike.