| 摘要 |
<p>In a method and a device (100) according to the present invention, two piezo-elements (10, 20) of a piezo-electric actuator (50) are driven with two voltages having a mutual phase difference. One of said piezo-elements (10, 20) is charged by a capacitive voltage step-up means (61, 62) to a voltage exceeding an available power supply voltage (VS). A capacitor is coupled to the piezo-element (10, 20), which divides the voltage of the piezo-element (10, 20) and simultaneously transfers part of the energy stored in the piezo-element (10, 20) to said capacitor. A part of the energy transferred to said capacitor is later transferred back to said piezo-element (10, 20), providing an energy-saving feature. The second piezo-element (10, 20) is driven in a similar way providing the required phase difference. In a further embodiment, the waveforms of the two driving signals are corrected using balancing capacitors.</p> |
