From 6d5ebea674194213faa6cd1bc2bebb5d560ab27e Mon Sep 17 00:00:00 2001 From: jbruce Date: Sat, 15 Dec 2018 15:58:22 -0500 Subject: [PATCH] -pid tuning instructions --- pid.md | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 pid.md diff --git a/pid.md b/pid.md new file mode 100644 index 0000000..3cf9f96 --- /dev/null +++ b/pid.md @@ -0,0 +1,52 @@ +* create a stepped schedule + +200 +220 +200 +220 + +* set i=0 +* set d=0 +* set p=5 + +run schedule +if oscillation is sustained stop +otherwise, double p + +once oscillation is sustained +* record P as Ku +* record period of oscillation as Pu + +set p=Ku/1.7 +set i=Pu/2 +set d=Pu/8 + +------------------------------------------------------------------------------- +another method (for just PI control) +https://pdfs.semanticscholar.org/e719/f259f6c93b9a897a214824e562c886aa80b9.pdf + + +use step schedule +set d=0 +set p=1 +you should see some overshoot and barely observable undershoot +if not, change p until that's true (up or down) + +next measure T between high peak and low peak +set i=T*1.5 +set p=.8*lastp + +p=1*.8 = .8 +i=1040-315 = 725s * 1.5 = 1088 + +------------------------------------------------------------------------------- +https://www.eurotherm.com/pid-control-made-easy + +similar to above for PI + +p=2*25=50 (that's 25F overshoot times 2) +i=725*1.5 = 1088 +d = 1088/5 = 217 + + +