Abstract |
Nowadays, piezoelectric actuators (PA) are used in fast power actuations and high power applications as requested in machine tools or helicopters flap applications. Regarding to the low power capability and high loss ratios of linear amplifiers, Switching Power Amplifiers (SA75X) is designed by Cedrat Technologies to drive piezoelectric actuators in such applications. The switching technique (up to 100 kHz) allows high current peaks required by impulse or by high frequency applications on large piezoelectric actuators (or actuators in parallel) and allows energy harvesting. Output voltage, current, and actuator position are monitored via controller board and using sensor feedbacks. Furthermore, the developed system (SA75X+actuators) can operate in open or closed loop system with an output signal frequency up to 1 kHz. The OEM version of the powerful switching amplifier (SA75D:20Amax) has a dimensions of 100x100x100mm, i.e. 1 litter, and a weight of 850g.The power ratio of this amplifier is thus of 1.5kVA/L and 1.75kVA/Kg. The output power capability, signal noise ratios, and control robustness of the SA75X justifies the proposed solution Theoretical, simulation, and experimental tests of the SA75D (20Amax) will be presented to improve the amplifier's performances. |