氏名STEFAN GERHARD MOZAR授与した学位博士

専攻分野の名称

工学

学位授与番号

博乙第学位授与の日付

平成３０年 ３月２３日

学位授与の要件

博士の論文提出者

４４９０号（学位規則第４条第２項該当）

学位論文の題目

論文審査委員Design Issues in Switched Mode Power Supplies for Television Receivers（テレビ受信機のスイッチモード電源装置の設計問題）
教授

舩曵 信生

教授

田野哲

教授

野上保之

学位論文内容の要旨
This thesis studies design issues in switched Mode Power Supplies for Television Receivers. The issues encounteredare due to the applications of new technologies, and they required innovative solutions. The solutions implemented
resulted in successful patent applications. This thesis consist of three chapters, which address three topics that areimportant to the application of switch mode power supplies for consumer applications, and were implemented in TVreceivers.
Chapter1
This chapter describes the design of an overvoltage protection circuit that was developed for voltage doublerapplications. There were two main factors that motivated this solution. One was an enormous cost reduction in thedoubler circuit. The other factor, which is more important is improved safety of power supplies. The protection circuit
has been patented by Philips. International patents were the issues for this design. This chapter describes some alternative
approaches to the protection circuit, and a mathematical model is developed to predict the performance of this circuit.
Some practical aspects to ensure a reliable design are also covered. Electrical design and safety evaluations are coveredand detailed test results are provided. The protection circuit passed all compliance requirements for IEC 65 and Dentori.
Chapter 2
A new root cause for an old problem has been identified, Sound-In-Vision (SIV). The new problem is due magnetic
cross talk in the flyback transformer. An overview of the problem is provided, and a method to diagnose the magnetic
cross talk is described. The cross talk issue is due to the increased demand for more audio power.
Chapter 3
Some innovative solutions are described to reduce standby power consumption. The first method described,
significantly reduces the standby power. The solution is not cost effective enough to make it to production. It also would
require amendments to IEC 65 safety standards. The other method described is a switching system that allows the useof remote controls to switch on equipment. This solution has been granted international patents, and it redefines astandby system.
Conclusion
This section summaries the innovative solutions and proposes possible further investigation in the consumer power
field.

論文審査結果の要旨

In this thesis, he studied design issues encountered in the development of a new switched mode power supply for atelevision receiver. The design issues encountered are not standard design problems which one encounters with known
technology in new applications. The issues encountered are due to advanced technology and novel solutions being
introduced in very competitive global markets, and for which there have not been any known solutions. Terrance Smith, aformer president of the IEEE Consumer Electronics Society defined Consumer Electronics as a high volume, low marginindustry. In an academic environment, the cost is generally not a driving factor, which is in stark contrast to consumer
electronics. Every cent that can be shaved off a product is import to the success of the product. Thus the design strategy
aims at cost effective solutions.

This thesis covers three chapters which relate to issues that are very important to consumer electronics. The first chapter
deals with voltage doubling, and proposes an innovative overvoltage protection solution. The solution proposed has been
patented internationally by Philips, and has found wide applications in the automotive industry. The second chapter deals
with Sound-In-Vision (SIV) cross modulation. The phenomenon has been around for many decades. The root cause of thisphenomenon changes as technology changes. In the early days of television, it was due to cross modulation between thesound and vision carriers in the Intermediate Frequency (IF) Stage of a receiver. Then, an underrated power supply was thenext major issue. In this thesis, again the root cause is in the power supply, but is due to magnetic cross talk in the core of
the switching transformer. The third chapter deals with standby power consumption. One of the early proposals promised
significant standby power reduction. The cost issues, however, were the stumbling block. In order to provide a cost effective
solution, some of the IEC 65 safety requirements were challenged. Thus, the first attempt did not progress into a product.
The proposal that is described in this thesis is the world’s first truly zero power standby solution. International patents havebeen granted for this solution.

From the overall evaluation of this thesis, the applicant has satisfied the qualification condition for the doctor degree inEngineering from the Graduate School of Natural Science and Technology at Okayama University.