Building a Light Electrical Vehicle - school Fab Lab project

A few thoughts:

  • Interest in LEVs has lead to BLDC motor+controller packages in low-kW territory being available at low cost from the usual can-I-buy-a-vowel sources. As for quality, caveat emptor. Your first will almost certainly not be the last.

  • 800 RPM is a relatively low figure for the power range; something 3-5 times that would be a more likely operating territory. Speed~voltage, Torque~current, and the I2R thing starts biting pretty hard as speeds decrease.

  • I’m not aware of a good “dummies” book for high-power electrical, perhaps for the same kind of reasons that I’m not aware of such pertaining to orthopedic surgery. Under the right (wrong?) conditions a person can draw an arc close to half a meter in length using sources of the sort you might encounter. Particularly in a secondary school context, it’d probably be better to get your lawyer involved before something ugly happens, rather than after.

  • Getting a basic handle on arc phenomena generally (mediocre starting point here) is good background, and understanding fuse ratings and what the current ratings of various items actually mean is quite important. For products like terminal blocks it might be a reasonable operating figure, for things like resistors it’s a figure that results in things hitting their maximum permitted temperature, and for some products such as FETs it can be a figure that became almost entirely theoretical as the tech improved by decimal places after the convention was established. Familiarize yourself with thermal modeling also; while you’ll likely not do work at a component level, the principles are quite relevant and transferable.

  • Understand your power source. Cell balancing is a universal concern regardless of chemistry, but particularly so if one’s going to adopt one of the fashionable-yet-tempramental lithium platforms.

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