【摘要】 超声波与金属的微小缺陷相互作用可产生非线性效应，由于非线性效应信号弱，在微小缺陷检测时必须采用高频高功率的发射装置来增强非线性效应信号强度。为此研究了一款高频大功率的超声驱动放大电路，该放大电路选用开关速度快、耐高压的氮化镓晶体管设计高效率的零电压开关（ZVS）型E类功率放大器，设计开关管保护电路、输入输出匹配电路以及可独立控制导通和关断驱动强度的栅极驱动电路，确保了高频高压大功率信号的高效输出。经测试，该E类功放驱动电路在工作频率为5 MHz，供电电压100 V时瞬时输出功率为223.9 W，峰值电压为150 V，直流转换效率为76.7%，表明该驱动电路可以用做高频大功率超声发射驱动。更多还原

【Abstract】 The interaction between ultrasonic waves and micro-defects in metals can produce nonlinear effects. However,the nonlinear effect signals are weak and require high-frequency and high-power transducers to enhance their intensity for micro-defect detection. Therefore,a high-frequency and highpower ultrasonic drive amplification circuit is proposed,the amplifier circuit uses GaN transistors that have fast switching speed and high withstand voltage to design an efficient Zero-Voltage-Switch(ZVS)type class E power amplifier,by designing a protection circuit for the switch tube,an input-output matching circuit,and a gate drive circuit that can independently control the conduction and shutdown drive strength,the efficient output of high-frequency,high-voltage,and high-power signals is achieved.The test results show that the designed class E power amplifier drive circuit has an instantaneous output power of 223.9 W and peak voltage of 150 V at a working frequency of 5 MHz and a supply voltage of100 V,and a DC conversion efficiency of 76.7%,indicating that the drive circuit can be used as highfrequency and high-power ultrasonic emission drive.更多还原