EXPERIMENTAL ANALYSIS OF GATE DRIVE CONTROL SYSTEM FOR SYNCHRONOUS DC/DC CONVERTER

The design of the PCB board is important as it affects the overall performance of the overall system. The most common problem that affects the performance and efficiency of the PCB board are partitioning of the circuits, the problem of interconnecting traces, grounding schemes and thermal management. Overall, the primary objectives of the project are to understand the process flow of PCB and to acquire knowledge about PCB fabrication. Meanwhile, the secondary objectives of the project are to apply high frequency DC-DC Converter on PCB fabrication and lastly to test and verify the output of PCB fabrication. SRBC-PWM and SRBC-compensator-AGD are successfully implemented on PCB board. The knowledge about PCB design is acquired and the problems overcome while fabricating PCB are managed to overcome

On flexibly integrating machine vision inspection systems in PCB manufacture

The objective of this research is to advance computer vision techniques and their applications in the electronics manufacturing industry. The research has been carried out with specific reference to the design of automatic optical inspection (AOI) systems and their role in the manufacture of printed circuit boards (PCBs). To achieve this objective, application areas of AOI systems in PCB manufacture have been examined. As a result, a requirement for enhanced performance characteristics has been identified and novel approaches and image processing algorithms have been evolved which can be used within next generation of AOI systems. The approaches are based on gaining an understanding of ways in which manufacturing information can be used to support AOI operations. Through providing information support, an AOI system has access to product models and associated information which can be used to enhance the execution of visual inspection tasks. Manufacturing systems integration, or more accurately controlled access to electronic information, is the key to the approaches. Also in the thesis methods are proposed to achieve the flexible integration of AOI systems (and computer vision systems in general) within their host PCB manufacturing environment. Furthermore, potential applications of information supported AOI systems at various stages of PCB manufacturing have been studied. It is envisaged that more efficient and cost-effective applications of AOI can be attained through adopting the flexible integration methods proposed, since AOI-generated information can now be accessed and utilized by other processes

Design and Realization of Electronic Measurement Systems for Partial Discharge Monitoring on Electrical Equipment

The monitoring of insulations that composing high voltage apparatus and electrical machines is a crucial aspect for a predictive maintenance program. The insulation system of an electrical machine is affected by partial discharges (PDs), phenomena that can lead to the breakdown in a certain time, with a consequent and significant economic loss. Partial discharges are identified as both the symptom and the cause of a deterioration of solid-type electrical insulators. Thus, it is necessary to adopt solutions for monitoring the insulation status. To do this, different techniques and devices can be adopted. During this research activity, two different systems have been developed at the circuit and layout level, which base their operation respectively on the conducted and on the irradiated measurement, in compliance with the provisions of current standards, if foreseen. The first system is based on the use of a classic signal conditioning chain in which gain value can be set through PC control, allowing the conducted measurement of partial discharges in two frequency bands, Low Frequency (LF) and High Frequency (HF). Based on these bands, the application of the system is diversified. In this case, the information obtained from the measurement can be analysed by an expert operator or processed by an intelligent system, obtaining in both cases information on the status of the machine under test. The second makes use of a UHF antenna built on PCB, which takes care of detecting the irradiated signal generated in the presence of discharge activity, which is then appropriately conditioned and processed by analog electronics, to then be acquired through a programmable logic, which interprets it and returns information on the status of the machine, which can also be checked by an expert user. The application of this system is linked to the type of insulation and the type of power supply adopted, which differentiate its characteristics. In both systems, the analysis of the measurement of partial discharges is suitable for the prevention of failures and the planning of suitable maintenance interventions

Modelling and simulation of paradigms for printed circuit board assembly to support the UK's competency in high reliability electronics

The fundamental requirement of the research reported within this thesis is the provision of physical models to enable model based simulation of mainstream printed circuit assembly (PCA) process discrete events for use within to-be-developed (or under development) software tools which codify cause & effects knowledge for use in product and process design optimisation. To support a national competitive advantage in high reliability electronics UK based producers of aircraft electronic subsystems require advanced simulation tools which offer model based guidance. In turn, maximization of manufacturability and minimization of uncontrolled rework must therefore enhance inservice sustainability for ‘power-by-the-hour’ commercial aircraft operation business models. [Continues.

A reference architecture for flexibly integrating machine vision within manufacturing

A reference architecture provides an overall framework that may embrace models, methodologies and mechanisms which can support the lifecycle of their target domain. The work described in this thesis makes a contribution to establishing such a generally applicable reference architecture for supporting the lifecycIe of a new generation of integrated machine vision systems. Contemporary machine vision systems consist of a complex combination of mechanical engineering, the hardware and software of an electronic processor, plus optical, sensory and lighting components. "This thesis is concerned with the structure of the software which characterises the system application. The machine vision systems which are currently used within manufacturing industry are difficult to integrate within the information systems required within modem manufacturing enterprises. They are inflexible in all but the execution of a range of similar operations, and their design and implementation is often such that they are difficult to update in the face of the required change inherent within modem manufacturing. The proposed reference architecture provides an overall framework within which a number of supporting models, design methodologies, and implementation mechanisms can combine to provide support for the rapid creation and maintenance of highly structured machine vision applications. These applications comprise modules which can be considered as building blocks of CIM systems. Their integrated interoperation can be enabled by the emerging infrastructural tools which will be required to underpin the next generation of flexibly integrated manufacturing systems. The work described in this thesis concludes that the issues of machine vision applications and the issues of integration of these applications within manufacturing systems are entirely separate. This separation is reflected in the structure of the thesis. PART B details vision application issues while PAIIT C deals with integration. The criteria for next generation integrated machine vision systems, derived in PART A of the thesis, are extensive. In order to address these criteria and propose a complete architecture, a "thin slice" is taken through the areas of vision application, and integration at the lifecycle stages of design, implementation, runtime and maintenance. The thesis describes the reference architecture, demonstrates its use though a proof of concept implementation and evaluates the support offered by the architecture for easing the problems of software change