THORLABS TPZ001, Руководство пользователя

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T-Cube Piezo Driver
Select Open Loop or Closed Loop as required.
Fig. 6.2 Position Setpoint Window
Loop Constants - When operating in Closed Loop mode, the proportional and integral
(PI) constants can be used to fine tune the behaviour of the feedback loop to changes
in the output voltage or position. While closed loop operation allows more precise
control of the output position, feedback loops need to be adjusted to suit the different
types of piezo actuator that can be connected to the system. The default values of 100
(proportional) and 100 (integral) have been optimised to work with most Thorlabs
piezo actuators, so usually these values can be left unchanged.
Integral Constant - sets the integral feedback loop constant for the selected
channel (0 to 255).
Proportional Constant - sets the proportional feedback loop constant for the
selected channel (0 to 255).
Control Settings
Voltage Step Size - Only applicable in open loop mode. This parameter specifies the
amount by which the piezo drive voltage is incremented or decremented, each time
the ‘Step’ button is clicked on the GUI panel.
Percentage Step Size - Only applicable in closed loop mode. This parameter specifies
the distance to move, each time the ‘Step’ button is clicked on the GUI panel, as a
percentage of the full travel range.
Note
When the TPZ001 and TSG001 are used in closed loop (with the TCH002)
the pot on the TPZ001 GUI panel (and the OUTPUT control on the top
panel of the unit) controls the position setpoint rather than voltage. This
position setpoint is a percentage (0-100%) reflecting min-max piezo
extension, e.g. for a 30 micron piezo stack, a position setpoint of 50%
equates to 15 micron. Further, when operating in closed loop mode, if you
click the ‘Set’ button on the GUI of the TPZ001 you are prompted to enter
a 'Position Setpoint [0-100%] - see Fig. 6.2 below.