From 983286d47b9cad48317d7bcbb6ca297a54af3e3a Mon Sep 17 00:00:00 2001
From: Marko Mecina <marko.mecina@univie.ac.at>
Date: Fri, 21 Jul 2023 13:23:47 +0200
Subject: [PATCH] add Python implementation of SMILE SXI IASW thermal PI
controller
---
Ccs/thermal_control.py | 113 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 113 insertions(+)
create mode 100644 Ccs/thermal_control.py
diff --git a/Ccs/thermal_control.py b/Ccs/thermal_control.py
new file mode 100644
index 0000000..0a2814e
--- /dev/null
+++ b/Ccs/thermal_control.py
@@ -0,0 +1,113 @@
+"""
+SMILE PI thermal control algorithm, Python implementation
+"""
+
+import numpy as np
+import time
+import threading
+
+
+def vctrl_ana_to_dig(v):
+ return int(v * 1024 / 3.3)
+
+
+class ThermalController:
+
+ ASW_PERIOD_MS = 125.
+
+ VCTRLLOWERVOLT = 0.2
+ VCTRLUPPERVOLT = 2.9
+ MAXDELTAVOLTAGE = 0.25
+
+ def __init__(self, temp_ref, cp, ci, offset, exec_per, model=None):
+
+ self.tempRef = temp_ref
+ self.coeffP = cp
+ self.coeffI = ci
+ self.offset = offset
+
+ self.temp = 0
+ self.voltCtrl = 0
+ self.voltCtrlUint16 = vctrl_ana_to_dig(self.voltCtrl)
+
+ self.tempOld = temp_ref
+ self.integOld = 0
+ self.voltCtrlOld = 0
+
+ self.hctrl_par_exec_per = exec_per
+ self._algo_active = False
+
+ self.model = model
+ self.log = []
+
+ self._thread = None
+
+ def set_temp_ref(self, temp):
+ self.tempRef = temp
+
+ def calculate_vctrl(self, temp):
+
+ deltaTime = self.hctrl_par_exec_per * self.ASW_PERIOD_MS / 1000
+ integ = self.integOld + deltaTime * (self.tempRef - self.tempOld)
+ voltCtrlRel = self.offset + self.coeffP * (self.tempRef - temp) + self.coeffI * integ
+
+ if voltCtrlRel < 0:
+ self.voltCtrl = self.VCTRLLOWERVOLT
+ elif voltCtrlRel > 100:
+ self.voltCtrl = self.VCTRLUPPERVOLT
+ else:
+ self.voltCtrl = self.VCTRLLOWERVOLT + (voltCtrlRel / 100) * (self.VCTRLUPPERVOLT - self.VCTRLLOWERVOLT)
+
+ if (self.voltCtrl - self.voltCtrlOld) > self.MAXDELTAVOLTAGE:
+ self.voltCtrl = self.voltCtrlOld + self.MAXDELTAVOLTAGE
+ elif (self.voltCtrlOld - self.voltCtrl) > self.MAXDELTAVOLTAGE:
+ self.voltCtrl = self.voltCtrlOld - self.MAXDELTAVOLTAGE
+
+ self.tempOld = temp
+ self.integOld = integ
+ self.voltCtrlOld = self.voltCtrl
+
+ self.voltCtrlUint16 = vctrl_ana_to_dig(self.voltCtrl)
+
+ def start_algo(self):
+
+ if self._thread is not None and self._thread.is_alive():
+ print('TTC algo already running')
+ return
+
+ self._thread = threading.Thread(target=self._algo_worker, name='TTCALGO')
+ # self._thread.daemon = True
+ self._algo_active = True
+ self._thread.start()
+
+ def _algo_worker(self):
+ print('TTC algo started (period = {:.1f}s)'.format(self.ASW_PERIOD_MS / 1000 * self.hctrl_par_exec_per))
+ while self._algo_active:
+ try:
+ t1 = time.time()
+
+ if self.model is not None:
+ self.temp = self.model.T_noisy
+ self.calculate_vctrl(self.temp)
+ self.model.set_heater_power(vctrl=self.voltCtrl)
+
+ self.log.append((t1, self.tempRef, self.temp, self.voltCtrl, self.coeffI*self.integOld, self.coeffP * (self.tempRef - self.temp)))
+
+ else:
+ self.calculate_vctrl(self.temp)
+
+ dt = (self.ASW_PERIOD_MS / 1000 * self.hctrl_par_exec_per) - (time.time() - t1)
+ if dt > 0:
+ time.sleep(dt)
+
+ except Exception as err:
+ print(err)
+ self.stop_algo()
+
+ print('TTC algo stopped')
+
+ def stop_algo(self):
+ self._algo_active = False
+
+ def save_log(self, fname):
+ np.savetxt(fname, np.array(self.log), header='time\tT_ref\tT\tV_ctrl\tcI*integ\tcP*(T_ref-T)')
--
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