I tweaked the regen braking this morning. As I mentioned earlier, the default parameters caused an oscillation or "lurching" during regen braking. I exchanged email with the support folk at Azure Dynamics about my theory - that the default 150-volt EE2NoRegenBat caused the controller to turn regen off and on as the voltage hovered near that value. The tech people agreed that setting NoRegenBat higher would be a fine workaround. I don't want to overcharge my batteries, so I decided to go with a higher NoRegenBat but a wider ramp (set by EE2RegenRamp). This chart illustrates what I did:
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEidlZjTqA9Hc4xV0rUnWArfx9crAIEucQ8b_RvpYQfK_naJqKgAnTOp5jP68A_W_WpuJqLaOFOX8XgAidEWCQtmq41RglT47iQjORh9EGjDchfbE7rm1KIxQESs0-_vH4W-h47R-GL5BUQ/s320/BrakeRampTweak.jpg)
EE2NoRegenBat is set to 160, instead of 150, and EE2RegenRamp is set to 34, instead of 12. This had a great effect, as the following chart shows. It plots braking as a percentage of max torque (which is 53Nm with my current 100A power max for regen):
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiEio59JcK5bqNKXUdg-8Xf9qZiN3OvoJX5zRdaWVIYFk9Ngk-JvhR2Sc30hFwA34aSIrZBKfwJc_Xn96YTHbUplvpJcAr06690Hi9s_8R6OS3tI9fBoMVibmb7kq0TA47AbqXskc19XuI/s320/TweakedBrakes.jpg)
Despite the fact that the sampling period (1 second) introduces some aliasing, you can clearly see the oscillations in the old, default parameters (the blue line). The red line shows a much smoother curve, with substantially reduced lurching. I plan on leaving regen enabled from this point on to see what it does to range.
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