Ogden ETR-8300, Инструкция по эксплуатации

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Although PID control has been used and proven to be an efficient controlling method by
many industries, PID tuning is difficult to achieve with some sophisticated systems such
as second and higher order systems, long time-lag systems, during set point change
and/or load disturbances. The PID principle is based on a mathematic model which is
obtained by tuning the process. Unfortunately, many systems are too complex to pre-
cisely describe in numerical terms. In addition, these systems may vary from time to time.
In order to overcome the imperfection of PID control, Fuzzy Technology was introduced.
What is Fuzzy Control? For example, take an automobile driver. Under different
speeds and circumstances, he can control a car well based on prior experience. The
driver does not need an in depth knowledge in the applied science of kinetic theory.
Fuzzy Logic like our driver from above uses a linguistic control which is different from the
numerical PID control. It controls the system based on experience and does not need to
analyze process metrics as does PID.
Although PID control has been used and proven to be an efficient controlling method by
many industries, PID tuning is difficult to achieve with some sophisticated systems such
as second and higher order systems, long time-lag systems, during set point change
and/or load disturbances. The PID principle is based on a mathematic model which is
obtained by tuning the process. Unfortunately, many systems are too complex to pre-
cisely describe in numerical terms. In addition, these systems may vary from time to time.
In order to overcome the imperfection of PID control, Fuzzy Technology was introduced.
What is Fuzzy Control? For example, take an automobile driver. Under different
speeds and circumstances, he can control a car well based on prior experience. The
driver does not need an in depth knowledge in the applied science of kinetic theory.
Fuzzy Logic like our driver from above uses a linguistic control which is different from the
numerical PID control. It controls the system based on experience and does not need to
analyze process metrics as does PID.
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Digital communications RS-485, RS-232 or 4 - 20 mA retransmission are available as an
additional option. These options allow the ETR-8300 to be integrated with a supervisory
control system and software, or alternatively drive a remote display, chart recorder or
data-logger. Digital communications RS-485, RS-232 or 4 - 20 mA retransmission are available as an
additional option. These options allow the ETR-8300 to be integrated with a supervisory
control system and software, or alternatively drive a remote display, chart recorder or
data-logger.
Three different ETR 1.
2.
3.
methods can be used to program the -8300: Use the ETR keys on
the front panel to program the unit manually, Use a PC and setup software to program
the unit via an RS-485 or RS-232 COMM port or Use the P12A, a hand-held program-
mer, to program the unit via programming port.
Three different ETR 1.
2.
3.
methods can be used to program the -8300: Use the ETR keys on
the front panel to program the unit manually, Use a PC and setup software to program
the unit via an RS-485 or RS-232 COMM port or Use the P12A, a hand-held program-
mer, to program the unit via programming port.
PROCESS
PID
FUZZY
MV PV
_
+
SV
+
+
Fuzzy Rule
Fuzzy Inference
Engine
Defuzzifier Fuzzifier
Digital
information
Language
information
Digital
information
Figure 1.1
Fuzzy PID System Block
Figure 1.1
Fuzzy PID System Block
The function of Fuzzy(Smarter) Logic is to adjust the PID parameters internally in order
to manipulate the output value (MV) and adapt to various processes. The function of Fuzzy(Smarter) Logic is to adjust the PID parameters internally in order
to manipulate the output value (MV) and adapt to various processes.
The Fuzzy Rule works like this:
If temperature difference is large, and temperature rate is large, then
MV is large.
If temperature difference is large, and temperature rate is small, then MV is small.
The Fuzzy Rule works like this:
If temperature difference is large, and temperature rate is large, then
MV is large.
If temperature difference is large, and temperature rate is small, then MV is small.
PID + FUZZY CONTROL PID + FUZZY CONTROL