SRS Labs CTC100, Руководство пользователя

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Operation 36
CTC100 Programmable Temperature Controller
the output is off when autotuning is started, the step response tuner runs because the relay tuner
would require a negative out9put.
A ggressive, moderate, and conservative tuning
Both the step response and relay tuners offer aggressive, moderate, and conservative tuning
options. Conservative tuning theoretically produces zero overshoot and is usually the best choice
when the temperature needs to follow a changing setpoint. The aggressive tuning option
theoretically produces 25% overshoot (although in fact it tends to be larger) and is usually the best
choice for applications in which the setpoint is constant. Moderate tuning produces a very stable
feedback loop that behaves reasonably in a wide variety of situations.
The figure below compares the system behavior when we change the setpoint from 60 to 70°C
after relay tuning with the aggressive, moderate, and conservative options. In this case, the
conservative tuning produces the best response.
However, the results are much different if we look at how the system responds to a thermal
disturbance. The next figure shows how well the system recovers when we start blowing air over
the heater with a fan. The setpoint is a constant 60°C. In this case, aggressive tuning produces the
best response.