Investigation on the efficiency potentials of anti-resonat driven high power ultrasonic systems compared to resonant operation

高功率超声波系统在许多工业应用中都得到了很好的应用。这些，即超声波焊接，需要更快和更节能的系统。这项提议的主要重点是增加关于超声波系统的知识，包括其电力电子学，特别关注瞬变和效率方面。目前还没有对不同的运营策略进行客观的比较研究。尤其是功率超声系统在反谐振状态下的工作还没有得到充分的研究，项目建议书旨在缩小这一差距。这将通过研究由超声换能器和功率电子设备组成的谐振和反谐振工作的超声系统来实现，并将研究新型半导体(这里：GaN)的使用是否能够减少内部和系统损耗以及在高开关频率(约1 MHz)下的开关损耗。一个基本的问题是，尽管开关频率很高，但仍有可能减小滤波器组件的尺寸。这包括对过滤器组件内的附加损耗的详细研究。为了使所开发的电力电子设备能够实现超声换能器的谐振和反谐振操作，必须提供不同的电压电平。这将通过开发两台合适的高频变压器来实现。将从漏感、内部电容和耦合电容等方面对其进行详细的研究和设计，并从稳定时间、稳定性和效率等方面研究适合的基于模型的控制算法。在此，将详细研究不同负荷水平下的运行方式。因此，将扩展和利用负载仿真系统进行比较研究。这允许高负载动态和非常好的重复性。一个重要的问题是，哪种操作模式是最佳的操作模式，谐振操作还是反共振操作。这些文献只提供了有限的关于压电元件的研究，它们提供了反共振具有主要优势的假设。用于高功率超声波应用的典型的预应力螺栓换能器还没有被介绍。此外，机械损耗、耦合损耗和介质损耗的分离和识别是该项目的一项重要任务。这将用于增加基本理解和模型验证。

High power ultrasonic systems are well established in many industrial applications. Those, i.e. the ultrasonic welding, have the need for faster and more energy efficient systems. The main focus of this proposal is increasing the knowledge on ultrasonic systems including its power electronics with a special focus on transient and efficiency aspects. In the state of art is no objective comparative study on the different operation strategies available. Especially the operation of power ultrasonic systems at anti-resonance is not sufficiently investigated.The project proposal aims to close this gap. This will be carried out by the investigation of an ultrasonic system consisting of an ultrasonic transducer and a power electronics in resonant and anti-resonant operation.It will be studied if the utilization of novel semiconductors (here: GaN) can reduce the internal and system losses as well as the switching losses at high switching frequencies (about 1 MHz). One essential question is the potential of reducing the size of filter components though the high switching frequencies. This includes a detailed research on the additional losses within the filter components. To enable the developed power electronics for resonant and anti-resonant operation of the ultrasonic transducer, different voltage levels have to be provided. This will be realized by developing two suited HF-transformers. Those will be detailed investigated and designed with respect to their properties including leakage inductance, internal and coupling capacitance.Suited model based control algorithms will be investigated with respect to settling time, stability and efficiency. Here the operation mode in combination with different load levels will be detailed studied. Hence a load emulation system will be extended and utilized for the comparative study. This allow high load dynamics and very good reproducibility.One important question, is which is the optimal operation mode, resonant or anti-resonant operation. The literature is providing limited studies on piezoelectric elements only, they provide the hypothesis that anti-resonance has major advantages. Typical pre-stressed bolted transducer for high power ultrasonic applications have not been covered yet. Moreover, the separation and identification of losses as mechanical, coupling and dielectric losses is an important task in the project. This will be used for increasing the fundamental understanding and model validation.