文章基本信息

标题：Ultrasonic Air Coupled Transducer Output Impedance Measurement Technique
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作者：Linas Svilainis ; Andrius Chaziachmetovas ; Tomas E. Gomez Alvarez-Arenas 等
期刊名称：Studies About Languages
印刷版ISSN：2029-7203
出版年度：2019
卷号：25
期号：1
页码：18-25
DOI：10.5755/j01.eie.25.1.22731
出版社：Faculty of Humanities, Kaunas University of Technology
摘要：The multi-period version of the optimal power flow can tackle the power dispatch problem of modern distribution system with distributed renewable energy sources and energy storage system. In this paper, a communication-efficient decentralized optimization algorithm (DOA) for the multi-period optimal power flow problem is presented. Firstly, the power management of modern distribution system is modelled as a linear conic optimization problem based on the conically relaxed power flow equations. Secondly, some ancillary variables at the junction bus are introduced to decompose the distribution system into several separate parts. Moreover, the DOA based on the extended version of Alternating Direction Method of Multipliers (ADMM) is proposed. The DOA evolves by partial local message exchanges without central coordination. Finally, the colouring scheme, which is in accord with the network colouring used in communication protocols to avoid packet collisions, is applied in the decentralized algorithm as well.
其他摘要：Estimation of the output impedance of ultrasonic transducers is required for electrical matching circuits design and for receiving amplifiers noise optimization. This paper presents a simple technique for transducer output impedance estimation using the same data acquisition system and signals that are conventionally used in non-destructive testing. A pair of ultrasonic transducers is used: one for transmission, one for reception. Received signal is recorded under low and high resistance load and transducer output impedance is then obtained from these two signals. Hence, this technique requires only one measurement channel and bias errors are low (no need for calibration). In addition, it is ground referenced and does not require the transducer to be removed from the positioning fixture. Experimental results obtained using different probing signals have been compared against conventional measurements obtained by an impedance analyser. DOI: 10.5755/j01.eie.25.1.22731
关键词：Amplifier;Output impedance measurement;Noise analysis;Noise density;Signal to noise ratio;Ultrasound transmission;Ultrasonic measurements