US 11,870,371 B2
Determining and applying a voltage to a piezoelectric actuator
Lars Henriksen, Tønsberg (NO); Tore Svortdal, Horten (NO); Euan Barron, Nairn (GB); Muhammad Asif Raza Azhar, Tampere (FI); Thi Kim Trinh Tran, Undrumsdal (NO); Nicolas Tallaron, Lyons (FR); and Pierre Craen, Embourg (BE)
Assigned to Polight ASA, Horten (NO)
Appl. No. 16/978,561
Filed by Polight ASA, Horten (NO)
PCT Filed Mar. 7, 2019, PCT No. PCT/EP2019/055653
§ 371(c)(1), (2) Date Sep. 4, 2020,
PCT Pub. No. WO2019/170793, PCT Pub. Date Sep. 12, 2019.
Claims priority of application No. 18160414 (EP), filed on Mar. 7, 2018.
Prior Publication US 2021/0021212 A1, Jan. 21, 2021
Prior Publication US 2021/0336560 A9, Oct. 28, 2021
Int. Cl. H02N 2/06 (2006.01); H04N 23/52 (2023.01); H04N 23/67 (2023.01); H10N 30/80 (2023.01); H04N 23/54 (2023.01); H04N 23/57 (2023.01); G02B 7/08 (2021.01)
CPC H02N 2/062 (2013.01) [H04N 23/52 (2023.01); H04N 23/54 (2023.01); H04N 23/57 (2023.01); H04N 23/67 (2023.01); H10N 30/802 (2023.02); G02B 7/08 (2013.01); G03B 2205/0061 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A method for determining and applying a voltage to a piezoelectric actuator (PEA) to achieve a given setpoint displacement, the method comprising:
determining, during an initial calibration procedure, a relation dcal(V) between a PEA displacement measure (d) and voltage (V) and a relation ttcal(V) between transition time (tt) and voltage, wherein the transition time is a charging or discharging time ΔT between two voltages VA and VB applied to the PEA, and wherein the relations are determined for both increasing and decreasing voltages to map hysteresis, and combining the determined relations to calculate a relation d(tt) between the displacement measure and transition time;
determining, after repeated biasing of the PEA, a new relation ttnew(V) between transition time and voltage, and substituting ttnew(V) in the calculated d(tt) to calculate a compensated relation dc(V);
providing a setpoint displacement measure, dsp or voltage Vs;
determining, using the compensated relation, dc(V), a voltage to be applied to the PEA to achieve dsp or a displacement measure derived from Vs; and
applying the determined voltage to the PEA.