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Unread 30-07-2016, 23:33
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Re: paper: 4 CIM versus 6 CIM theoretical calculations

A great overview of the continued advantages of 6 CIMs over 4 - provided that you watch the total current!

Assuming 200A for the drive train is simplistic, but a good way to compare apples to apples. No matter what the battery state is, you will have a certain limited current you can draw from it before beginning the brownout process.

The first (and so far only) technical error was the sentence that spans from the first page to the second. It should read something like:
Quote:
Originally Posted by asid61, edited
If the speed goes down by 1/10th of the max speed, the current will go up by 1/10th of the difference between stall current and free current, and so forth.
This does not change any of the high-level conclusions.

Another thing to consider if planning a drive train with current limiting is whether using some other motor will be more effective to your strategy than CIMs. A cursory review of the mini-CIM finds it to be inferior in most cases, as it has lower efficiency than the CIM at any given current draw, but there are probably cases where it is the proper choice, due to weight considerations or specific needs. If you're going to do proper current/speed and/or thermal monitoring, you may want to add the 775 pro or other low thermal mass motor to your considerations.
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