TEMPERATURE CONTROL DEVICE AND ABNORMALITY DETERMINING METHOD

PROBLEM TO BE SOLVED: To detect a device failure such as sensor peeling and an abnormality of a temperature measured value. SOLUTION: A temperature control device includes an AT executing part 4 for executing limit cycle automatic tuning (AT) which sets PID parameters of a PID calculating part 2 by generating a limit cycle, a maximum temperature rise change rate detecting part 6 for detecting the maximum temperature rise change rate in executing the AT, a maximum temperature fall change rate detecting part 7 for detecting the maximum temperature fall change rate in executing the AT, a threshold calculating part 8 for determining a threshold for abnormality determination using the maximum temperature rise change rate and the maximum temperature fall change rate, a change rate detecting part 9 for detecting the change ratio ΔPV of a temperature PV measured at normal control operation by the PID calculating part 2, an abnormality determining part 10 for determining an abnormality when the change rate ΔPV becomes larger than the threshold, and a determination outputting part 11 for informing the determination result of the abnormality determining part 10 to an operator. COPYRIGHT: (C)2011,JPO&INPIT