The Chien-Hrones-Reswick autotuning method focuses on setpoint response and disturbance response. This method provides formulas for 0% and 20% overshoot.
Note��You must use the PID Autotuning Design VI to implement this autotuning method. Select the Chien-Hrones-Reswick polymorphic instance and use the Tuning specifications input to configure which formula you want to use. |
The following tables shows the Chien-Hrones-Reswick recommendations for each tuning formula:
Regulator � 0% overshoot | |||
---|---|---|---|
Controller | Kc | Ti | Td |
P | 0.3TP/ | � | � |
PI | 0.6TP/ | 4 | � |
PID | 0.95TP/ | 2.4 | 0.42 |
where TP is the time constant and is the deadtime.
Regulator � 20% overshoot | |||
---|---|---|---|
Controller | Kc | Ti | Td |
P | 0.7TP/ | � | � |
PI | 0.7TP/ | 2.3 | � |
PID | 1.2TP/ | 2 | 0.42 |
where TP is the time constant and is the deadtime.
Servo � 0% overshoot | |||
---|---|---|---|
Controller | Kc | Ti | Td |
P | 0.3TP/ | � | � |
PI | 0.35TP/ | 1.2 | � |
PID | 0.6TP/ | 0.5 |
where TP is the time constant and is the deadtime.
Servo � 20% overshoot | |||
---|---|---|---|
Controller | Kc | Ti | Td |
P | 0.7TP/ | � | � |
PI | 0.6TP/ | � | |
PID | 0.95TP/ | 1.4 | 0.47 |
where TP is the time constant and is the deadtime.