【摘要】 为了提升压电陶瓷驱动电路在高压工况下的电流输出能力，改进了传统的复合放大器，在其从运放的反馈环路中增添了一级乙类功率放大电路以提高输出电流。利用运放的负反馈网络对功率放大电路进行控制，可以改善乙类功率放大电路的输出特性。针对压电陶瓷作为容性负载引起的运放稳定性问题，使用隔离电阻、超前补偿法对改进后的复合放大器进行外部相位补偿。使用简易的运放内部模型对补偿原理进行了分析，并通过仿真对环路增益Aβ的相位余量进行验证。实验表明，该驱动电路在7.6μF容性负载下的输出失调电压为0.46 mV，输出噪声峰-峰值为3.4 mV,-3 dB带宽为1.5 kHz，输出200 Hz、0～120 V正弦波时滞后相移约为8.5o，最大瞬时输出电流限制约在0.9 A。更多还原

【Abstract】 In this study, a conventional composite amplifier was improved to enhance the current output capacity of piezoelectric ceramic drive circuits under high-voltage conditions. A Class B power amplifier circuit was incorporated into the feedback loop from the operational amplifier to increase the output current. The output characteristics of the Class B power amplifier circuit were enhanced by controlling the power amplifier circuit via the negative feedback network of the operational amplifier. To mitigate the adverse effects of piezoelectric ceramics(that function as capacitive loads) on the stability of operational amplifiers, external phase compensation was implemented in the improved composite amplifier using isolation resistors and the lead compensation method. The compensation principle was analyzed using a simple internal model of the operational amplifier, and the phase margin of the loop gain(Aβ) was verified through simulations. The experiments results showed that under a 7. 6 μF capacitive load, the output offset voltage, peak-to-peak output noise,-3 dB bandwidth, lag phase shift in a 200 Hz 0-120 V sine-wave output, and maximum instantaneous output current of this driving circuit were 0. 46 mV, 3. 4 mV, 1. 5 kHz, ～8. 5°, and ～0. 9 A, respectively.更多还原