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Week 25 (Apr. 3, 2019): Current Amplification Solved via Buck Converter


Today, we made the decision of going with the 12V, 600mA induction coil set, as they allowed for a greater distance between the transmitter and receiver, which was a maximum distance of 0.787 inches, as opposed to the 5V, 1500mA induction coil set, which had a maximum charge distance of 0.5 inches.

As a reminder, we are implementing induction charging, also known as wireless charging, to charge the 3.7V Li-ion battery at designated charging stations within the track. This helps to enforce autonomy, which will further eliminate human intervention and manual maintenance of the system.

Because the charge current is smaller, we tried to find a way to increase the charge current used to charge the battery. We settled upon using a buck converter, which decreases voltage with the advantage of increasing current. The buck converter would be placed after the induction receiver and before the battery charger. After some testing, we found that the buck converter could amplify the current to the desired 1A. However, since the battery charger has a maximum charge current of 1A, we decided to lower the charge current to a safer 800mA.

An image of the buck converter is shown below, as well as the Amazon purchase link with all of the product details:   






Source: https://www.amazon.com/gp/product/B07JNQFV7F/ref=ppx_yo_dt_b_asin_title_o01_s01?ie=UTF8&psc=1  

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