MINIATURIZATION OF AN ACTIVE VIBRATION CONTROL SYSTEM BASED ON PIEZOELECTRIC TRANSFORMERS

摘要

A piezoelectric transformer (PT) has many advantages over traditional one, such as light weight, little size,potentially low price, high energy density, zero EMI. In addition, one of its most important features is that the ceramic material, which PT is made of, is capable for high-voltage insulation. On the other hand,switching-power amplifier has the characteristics of small size and low energy consumption. Based on the two technologies above, this paper designs a kind of miniaturized system for active vibration control using piezoelectric transformers instead of electromagnetic transformers, and switching power amplifiers instead of linear power amplifiers. In this system, low DC voltage is converted into high DC voltage by a DC-DC converter,the high DC Voltage serves as the bus voltage of the amplifier circuits. Reference signals are input to DSP system after signal conditioning, PWM signals are sent out according to the relevant control algorithms, and are then magnified by the switching circuits. Finally, the signal is demodulated by a low-pass filter to excite actuators of an active wbration control system.