TECO E510s Series - Page 242

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 PID Control Setting
PID control block disgram, the following figure shows PID control block diagram.
Figure 4.3.81 PID control block diagram
 PID Tunning, use the following procedures to start PID control
(1) Enable PID control
 Set 10-03 to a value greater than "xxx0b").
 Increase the proportional gain (10-05) to the highest value possible without causing the
system to become unstable.
 Decrease the integral time (10-06) to the lowest value possible without causing the system
to become unstable.
 Increase the differential time (10-07) to the highest value possible without causing the
system to become unstable.
(2) The PID control serves to maintain a given process within certain limits whether it is pressure,
flow etc. To do this the feedback signal is compared to the set value and the difference
becomes the error signal for the PID control.
(3) PID output polarity can be selected with parameter 10-03 (setting = xx0xb: PID output forward,
setting = xx1xb: PID output reversal). When PID output is chosen to reverse, and if PID input is
negative, the output frequency of PID will gain. On the contrary, PID output is chosen to
forward, and if PID input is minus, the output frequency of PID will decrease.
(4) PID feedback value can be adjusted using parameter 10-04 (PID feedback gain) as well as with
the analog input gain and bias for terminal AI1 or AI2.10-14 (Integral Limit) Used to limit the
integral output to prevent motor stall or damage to the system in case of a rapid change in the
feedback signal. Reduce the value of 10-14 to increase the inverter response.
 PID Bias (10-09)
Used to adjust the offset of the PID control. The offset value is added to the frequency reference as
compensation. Use parameter 10-24 (PID output gain) to control the amount of compensation.