Gen2/Motor Controller/Feature Usage

From Unofficial Zero Manual
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This describes how the Sevcon controller's features are used on Zero models.

Throttle
Sevcon provides the throttle with two mappings:
  1. Mapping voltage to value in the first place (separately for forward and reverse)
  2. An "input characteristic" profile which has linear, curved, crawl, and user-defined segmented options.
The controller also supports:
  • Control modes targeting speed (used through 2012) versus torque (used in 2013+).
    The control mode translates the throttle signal into motor operation, so it makes the throttle target a speed or a level of torque.
  • Dual throttle inputs.
  • Regen proportional to the throttle.
  • Directional throttle.
  • Speed limit proportional to throttle.
  • Reverse speed limit.
Regen
The Sevcon controller manual refers to regen as braking, and has a number of recommendations and features disabled to help prevent wheel lockup for "on-highway applications".
Braking
The Sevcon can also apply reverse torque as braking or a reverse gear, and supports separate speed and torque limits while the motor is rotating in reverse, very important if used on a Zero since motorcycles are unstable when reversed so must operate within human walking speeds.
OEM Programming
Zero programs the Sevcon controller for their needs, above and beyond DOT, NHTSA, and EU vehicle manufacturing standards.
Some of this is a bunch of settings and some of this seems to be a custom version of the firmware code.
The new IPM motor may have demanded further customization than previous models, where custom firmware code is particularly relevant.
Settings can be changed and restored, but not code without some OEM-supported technical assistance.