Tuning matching plays an important role in the system of ultrasonic generator. First, when the ultrasonic transducer is in the resonant state, it usually presents a capacitive state. Through matching network, the capacitive impedance is compensated, so that the load of the ultrasonic generator is as close as possible to the pure impedance state, so as to reduce the reactive power component. Impedance matching: According to AC theory, when the power supply impedance and load impedance are equal, the load can obtain the maximum power. Because the ultrasonic transducer has the characteristic of impedance model, the impedance characteristic of the power supply load of the whole ultrasonic generator is changed by matching network, and the appropriate parameters are selected to make the load impedance close to the power supply impedance, so that the ultrasonic wave can obtain larger electric power. At present, domestic and foreign scholars have carried out in-depth research on the matching network of ultrasonic transducers. Based on the equivalent circuit, a simple L-C matching network is used to obtain the maximum conversion power and improve the efficiency of the ultrasonic transducer.

From the perspective of excitation mode of ultrasonic transducer, it can be divided into two excitation modes: self-excitation mode and self-excitation mode. Because the vibration modes of the two generators are different, for its excitation generator, it is necessary to know the specific parameters of the ultrasonic transducer, including the working frequency. The inductance value to be connected can be roughly calculated by calculating formula, while the self-excitation generator usually determines the working frequency by connecting the inductance value. From the point of view of impedance matching, how to do this is analyzed. A matching network is composed of a pulse transformer and R, L and C between the generator and the ultrasonic transducer. Based on the analysis of the basic principle of ultrasonic transducer and the electrical equivalent circuit, the capacitance matching, inductance matching, LC matching and T-type matching are studied, and the basic calculation methods of these matching modes and parameters are given, and each matching is analyzed. The advantages and disadvantages of these two matching methods have good reference value for static matching. By analyzing the characteristics of series inductance matching and parallel inductance matching on the frequency of ultrasonic transducer, combining the advantages of these two matching methods, an L-type matching network is proposed, and the effects of these matching methods on working frequency and the changes of electromechanical coupling coefficient are compared, which provides one for static matching network. Ways of planting.