| The next generation of space telescopes will require primary mirrors that push beyond the current state of technology for mirror fabrication. These mirrors are large, have low mass per unit area, must maintain diffraction limited performance at cryogenic temperatures. Traditionally, large mirrors are made by polishing an accurate surface onto a glass substrate that is large enough to be rigid and stable on its own.The mirror blanks are typically made to be thick, although often lightweighted, to achieve high specific stiffness. The next generation of space telescopes will make mirror several meters across with mass/area< 15 kg/m2. This density corresponds to less than 7 mm thickness. It is prohibitive with current technologies.To solve the technical problem above, it has developed an active mirror, which uses closed-loop control of the surface. There has a thin membrane as the optical surface, which is attached to a stiff lightweight support structure through a set of screw-type actuators. This system allows periodic adjustments with the actuators to maintain the surface figure. The optical surface accuracy and stability are maintained by the active system. It usually adopts piezoelectric ceramic micro-actuator which controls the adjustment of micro-displacement.This paper firstly gave a detailed introduction of the piezoelectricity effect and principle of piezoelectric ceramic. Piezoelectricity effect reflects the relationship between the elasticity deformation of piezoelectricity material and electric performance mutual coupling. When piezoelectricity material go out of shape under the effect of outside force, produce the electric charge of on the surface, this kind of effect not have electric field characteristics and produces the electric charge because of deformation, and is named the straight piezoelectricity effect. When exert an electric field to this kind of piezoelectricity material, it is not only polarized, but also produces deformation. This phenomenon is called against piezoelectricity effect or the flexible effect of the electricity. Piezoelectric ceramic micro-actuator is just made for this kind of against piezoelectricity effect or the flexible effect of the electricity. Then we introduced displacement characteristic, temperature characteristic, delaying characteristic, static characteristic and dynamic characteristic of the piezoelectric ceramic. With the development of micro-displacement technology of piezoelectric ceramic, various kinds of special-purpose drive power used for the micro-displacement mechanism of piezoelectric ceramic arise at the historic moment. Theoretically, this power can be divided into two categories: voltage controlling and of electric charge. The voltage type power has two kinds mainly: One kind is that switch type based on DC converter. Switch power has little loss power with high efficiency and small outline, but have relatively high output ripple and narrow frequency responding band. Another kind is DC-magnifying power, the characteristic of this circuit is that the frequency responding range is relatively wide frequently, but can not obtain high output precision. We designed a new type of piezoelectric ceramic on the basis of the general used DC magnifying power.Piezoelectric ceramic micro-actuator needs a driving power, which must between –20V and 100V. So we need a power supply magnifier to get the needed power. First we compute the parameters of power magnifying, and choose the appropriate power supply according to these parameters. We chose the power amplifier PA45 of Apex because it matches perfectly our needs in this system. All the basic architecture, working characteristics and typical application circuits were analyzed. And finally based on PA45 we constructed the driving power of piezoelectric ceramic. During the design of main circuits, some aspects related with the output need to be considered such as self-oscillation, the noise compensation circuits, and the protection on the output and velocity conversion. The circuit simulation system Pspic...
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