Abstract
Piezoelectric stack actuators (PESAs) are widely used in applications requiring a fast response, high resolution, and high accuracy. The self-heating of a PESA during continuous drive with a large amplitude at high frequencies can change its voltage displacement and charge displacement characteristics. These changes can lead to a loss of stability and inaccurate PESA positioning systems. In this paper, we confirmed that by using our proposed forced liquid cooling, the changes to the dynamic characteristics and the impedance of a PESA due to the fact of self-heating could be reduced. Voltage displacement curve measurements at 10 kHz demonstrated that with natural heat dissipation, the amplitude of PESA increased by 15% due to the self-heating compared to the amplitude measured at the start of driving but only by 3% with forced liquid cooling. The displacement-to-charge ratio decreased by 12% compared to that at room temperature with natural heat dissipation, while it increased by 1% during forced liquid cooling. In the measured frequency response of the voltage displacement transfer function, the increased temperature changed the gain and phase of the first and secondary vibration modes above 20 kHz with natural heat dissipation. Forced liquid cooling also reduced the variations in the frequency response of the voltage displacement transfer function.
Highlights
Piezoelectric stack actuators (PESAs), we propose a forced liquid cooling method using silicone oil as the coolant
We evaluated how the voltage displacement and charge displacement curves at high frequency, the frequency response of the voltage displacement transfer function, and the impedance of the PESA changed when the temperature fluctuations in the PESA were reduced by applying forced liquid cooling
We measured the frequency response of the voltage displacement transfer function with and without forced liquid cooling
Summary
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. A high-order linear filter is sometimes used in the feedback controller to cancel the resonances that cause control instability [4] This method is vulnerable to changes in dynamics and can be destabilized. It has been reported that the response characteristics and positioning accuracy change with increasing temperature in positioning systems that combine a PESA and feedback control [17]. We evaluated how the voltage displacement and charge displacement curves at high frequency, the frequency response of the voltage displacement transfer function, and the impedance of the PESA changed when the temperature fluctuations in the PESA were reduced by applying forced liquid cooling.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
