大功率超声波逆变电源的设计

发布时间：2018-05-01 22:14

本文选题：超声换能器 + 串联谐振　；参考：《南京理工大学》2014年硕士论文

【摘要】：现代机械加工中超声波塑料焊接的应用越来越广泛,正成为一项非常有前景的加工技术。实现高质量、高效率的超声波焊接加工,需要高质量的超声逆变电源,而寻找正确的工作频率是高效率超声电源的关键步骤。超声换能器的谐振频率包括串联谐振频率和并联谐振频率,其中串联谐振频率又称为机械谐振频率,是换能器的最佳工作频率。在该频率上,转换效率最高。这就要求超声逆变电源能工作在该频率上。论文在仔细分析超声换能器的机电特性基础上,对谐振电路的工作特性进行了研究,旨在研制一种高效率、高质量的逆变电源。主要内容包括： (1)根据机械与电的等效原理,分析及计算超声换能器的等效电路特性和特性阻抗,所获结论是：超声换能器可以利用匹配电感平衡自身的体电容。 (2)通过电路仿真的结果,证实匹配电感不仅可以平衡换能器的体电容,还可以利用串联谐振方式提升工作电压,使得振动的效果更好。 (3)对超声逆变电源的控制方式进行了分析,提出了自己的控制方式。利用手动调节电位器控制工作频率,观察换能器上的电流电压波形以寻找最佳频率点,确定工作频率。 (4)对可控整流环节及DC/AC逆变环节的电路设计进行了详细介绍,并对所需要的关键器件例如滤波电感、匹配电感、主变压器的设计制作作详细说明。 (5)试验中,重点介绍了换能器的串联谐振频率的寻找方法。通过试验,证实了结果满足设计要求。经过实际带载工作,证明了设计方案可靠、适应性强、转换效率高,因此,该设计方案具有良好的实用和推广价值。
[Abstract]:Ultrasonic plastic welding is more and more widely used in modern machining, and is becoming a very promising processing technology. In order to realize high quality and high efficiency ultrasonic welding, high quality ultrasonic inverter power supply is needed, and finding the correct working frequency is the key step of high efficiency ultrasonic power supply. The resonant frequency of ultrasonic transducer includes series resonant frequency and parallel resonant frequency. The series resonant frequency, also called mechanical resonance frequency, is the best working frequency of the transducer. At this frequency, the conversion efficiency is the highest. This requires the ultrasonic inverter to work at this frequency. Based on the detailed analysis of the electromechanical characteristics of ultrasonic transducer, the working characteristics of resonant circuit are studied in order to develop a high efficiency and high quality inverter power supply. The main elements include: 1) according to the principle of mechanical and electrical equivalence, the equivalent circuit characteristics and characteristic impedance of ultrasonic transducer are analyzed and calculated. The conclusion is that the ultrasonic transducer can balance its volume capacitance by matching inductance. The results of circuit simulation show that the matching inductor can not only balance the volume capacitance of the transducer, but also enhance the working voltage by using the series resonance mode, which makes the vibration effect better. The control mode of ultrasonic inverter power supply is analyzed and its own control mode is put forward. By manually adjusting the working frequency of the potentiometer, the current and voltage waveforms on the transducer are observed in order to find the best frequency point and determine the working frequency. The circuit design of controllable rectifier and DC/AC inverter is introduced in detail. The key devices such as filter inductor, matched inductor and main transformer are described in detail. In the experiment, the searching method of the series resonant frequency of the transducer is introduced emphatically. The experimental results show that the results meet the design requirements. It is proved that the design scheme is reliable, adaptable and conversion efficiency is high. Therefore, the design scheme has good practical and popularizing value.
【学位授予单位】：南京理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TB552

【参考文献】