YASKAWA V1000 Series Technical Manual page 123

D Control
n
Overshoot refers to a control loop tendency to overcompensate for an error condition, causing a new error in the opposite direction. Derivative action
provides an anticipatory function that exerts a "braking" action on the control loop. When combined, the proportional integral, and derivative actions
provide quick response to error, close adherence to the setpoint, and control stability.
PID Operation
n
To better demonstrate how PID input works, the diagram below shows how the output changes as the deviation between the target value and the feedback
level are kept constant.
Using PID Control
n
Applications for PID control are listed in the table below.
Application
Machinery speed is fed back and adjusted to meet the target value.
Speed Control
Synchronous control is performed using speed data from other machinery as the target value.
Pressure Maintains constant pressure using pressure feedback.
Fluid Control Keeps flow at a constant level by feeding back flow data.
Temperature Control Maintains a constant temperature by controlling a fan with a thermostat.
YASKAWA ELECTRIC SIEP C710606 18A YASKAWA AC Drive – V1000 Technical Manual (Preliminary)
Offset
Amount
D Control
Description
Time
PID Control
I Control
P Control
Time
5.2 b: Setup
Sensors Used
Tachometer
Pressure sensor
Flow rate sensor
Thermocoupler
Thermistor
5
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