Design of Piezoelectric Power Amplifier Used for Adaptive Structural Vibration Control

Some capacitive loads of power amplifier usually bring inexpectant problems such as phase lag and impulse hunting. So a new power amplifier which is suitable for driving piezoelectric ceramics in the filed of piezoelectric intelligent structure´s adaptive vibration control is designed on the base of PA95 core chip which is produced by APEX Corporation. By adding feedback network, compensation loop and protect circuit, the power amplifier can amplifies signal´s voltage amplitude from plusmn5 V to plusmn350 V in frequency range of 5 KHZ while output transient current can reach 200 mA, steady output current is 120 mA and steady voltage ripple is below 150 mV. The power amplifier´s stability is analyzed and result shows that power amplifier´s signal response is steady in frequency range of 1 MHZ because phase margin is always larger than 45 degree. At last this power amplifier is applied to experimental platform of intelligent structure´s active vibration control which follows adaptive filtering LMS algorithm and gains excellent experimental control efforts.