Tuesday, November 10, 2015

v0.1.7 source released

Today I posted v0.1.7 of the Arudino Alternator Regulator source code, look under the SOURCE resource tab above.

This release is based largely on field feedback (thank you A-P) and is able to better 'regulate' the temperature of an alternator.  It has two changes in it:

    1) Bug Fix - Prevent any PWM increase if the Alt is at (>=)  its target temperature.
                       Prior would block PWM  increases only when the alt was over temp. (>)
     2) Refinement - Increased gain of PID tuning for Alt Temperature.
              #define KpPWM_TA_SENSITIVITY                0.500      
              #define KdPWM_TA                                        0.750
                ( Was:  0.200 / 0.500  )

The old code 'worked', but tended to allow the alternator to overshoot its upper temperature limit and ultimately triggering an over-temperature pull-back.   With the above changes we can now expect to see a more stable and smooth regulation around alternator temperature when needed.

I want to thank A-P for his live field feedback on this area.  Having feedback from a wide range of installations helps this project tremendously.

As kind of a review, the Arduino Alternator Regulator actually has 4 regulation points (vs. the 1 or perhaps 2 of more common regulators).
  • Battery Voltage - most all regulators do this :-)
  • Battery Current
  • System Wattage / Engine load
  • Alternator Temperature - some 'advanced' regulators do this as well

Each of these 4 regulation points along with other traps and system monitors (e.g., battery temperature, RPMs, etc) can have an effect on how hard the alternator is driven.  Alternator Temperature can come up in a cramped engine space, and to be honest if an install is operating under this mode one should perhaps look at the overall installation:  Perhaps the alternator is too small (or overrated, aka "Too Much Marketing" put into it).  And/or there is a significant cooling issue in the engine room.   But in any case - rest assured, the Arduino Alternator Regulator will manage things as best as can be done given each installation.

Oh, one more change:  I am now using notepad++ as my default editor.  One of its features is the ability to automatically replace tabs with spaces.   And I have turned that on.  Prior source was edited with a tab spacing = 8, and I know many folks use spacing = 4.  By just using spaces the code should 'look good' no matter which editor you are using.