The Design Of Excitation Power Supply For Ultrasonic Guided Wave Detection

Comparing with traditional NDT technologies, the ultrasonic guided wave technology is faster, more reliable and economical. Therefore, it is widely applied to inspect a variety of structures, such as pipe, railway and bolt. The excitation power supply plays an important part in the study of ultrasonic guided wave detection system, and develops as the ultrasonic guided wave technology develops. At present, ultrasonic guided wave detection systems almost are made by foreign organizations and hard to further develop. The excitation power supply also could be made up of independent devices. However, those purchasable devices are usually functional, but too large, too heavy to take outside easily. Thus, the design of the excitation power supply for ultrasonic guided wave detection, on basis of features of the ultrasonic guided wave detection, has reference value for the study of ultrasonic guided wave technology.The excitation power supply for the ultrasonic guided wave detection has two parts: the narrow-band waveform generator and the power amplifier.On basis of the narrow-band characteristic of ultrasonic guided wave detection signal, it is proposed to realize the narrow-band signal by modulating the signal-frequency signal with Hanning window. The waveform generator system is separated into carrier signal and modulation signal module, control circuit module, AM and analog switch module. Each module is in detail described. The simulation proved its feasibility.The design of the power amplifier includes design indexes, circuit structure design, simulation and debugging. First of all, determine a proper class of operation and circuit structure. Secondly, separate the system into dc biasing circuit, filter circuit, linearization technology, cooling technology, and broadband matching network. In detail describe the function, circuit structure, and design method of each module. At last, the simulation and circuit debugging prove the feasibility, and provide experience for further improvement.This design proposes a feasible design scheme of the excitation power supply for the ultrasonic guided wave detection. The debugging circuit basically reaches the design index. And the reasons for that unreached index are put forward, as well as how to improve the circuit.