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Old 10-26-2014, 12:31 PM   #1272 (permalink)
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Originally Posted by thingstodo View Post

Between single-pedal driving, the width of the 'coast' throttle range, the max regen on the throttle pedal versus pushing on the brake ... there are a lot of options that people can experiment with.

How one would configure these options, keeping the various variables or setpoints straight in your head ... remains a challenge.

The GEVCU uses a webserver built into the ethernet interface to deal with the settings, showing them on a web page and allowing for graphical representation of the options they support. This is not as complex as you have already programmed, but it's somewhere that is available to review code ... and borrow code that is already running.

The GEVCU is Arduino based, so I don't think that the code will not be verbatim, but the web interface should be close.
Generally the issue is how to best ramp the motor to avoid commanding huge amounts of torque. During acceleration this is not generally an issue, but during regen you have all the friction losses aiding and therefore any subtle movement can command a LOT of torque. In addition, as the voltage increases the field also gets stronger and therefore, even more torque, however at a certain point the battery will not be as receptive, so either rheostatic braking is used in conjunction or the torque will go down to keep the DC-LINK within limits.

What gear one is using also affects the performance.

On a PM motor is very easy to relate current to torque and therefore only a few equations are needed, but on an IM this is not as linear.
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