Environmental Effects; Humidity; Temperature - Aerotech QNP3 Series Hardware Manual

QNP3 Hardware Manual
Figure C-6: Estimated power dissipated as a function of frequency and applied voltage for a
Temperature rise is proportional to the power dissipated in the actuator. To determine the temperature rise of
the piezo actuator or stage requires in-depth knowledge of the exact stage characteristics and design
(materials, contact area, etc.). By examining
concern at very large signal amplitudes (e.g., high voltage or large amplitude position) and high frequencies.
For most positioning applications, the power dissipation and temperature rise in a piezo nanopositioning
stage is negligible. For applications requiring large position oscillations and high frequencies, contact
Aerotech's Application Engineering Department.
We will be happy to assist you in sizing the correct piezo nanopositioning device for your exact application.
C.3.7 Environmental Effects
C.3.7.1 Humidity
One of the most important factors for ensuring long life is to protect the piezo actuator against humidity. For
this reason, Aerotech uses specially-sealed coatings on the actuators that protect the actuator from
moisture. Operation at 60% or lower RH environments is preferred as it helps further prolong the life of the
actuator.
C.3.7.2 Temperature
Piezo actuators can be designed to operate at very high temperatures and extremely low temperatures
(cryogenic). The extreme upper limit of operation is the Curie temperature of the piezo material. At this
temperature, the piezo material loses its piezoelectric effect. Curie temperatures of piezo actuator materials
fall between 140°C and 350°C. However, piezoelectric properties are temperature dependent. For this
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typical piezo actuator with a 4 µF capacitance
Figure C-6, one can see that heating typically only becomes a
Appendix C
Piezo Engineering Tutorial
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