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The primary goal of engineering outreach is to attract prospective students to engineering education and the engineering profession. Gifted students, especially those identified as possessing unusually high abilities in science and technology, are especially promising students to attract to careers in engineering. It is critical to cultivate these students' interests and develop their potential for engineering while encouraging them to pursue engineering studies beyond K-12 education. This article presents examples of the successful learning outcomes of an ongoing University-based Electronics Technology Project Study (UETPS) program, a joint endeavor between the IEEE Hong Kong Section, the Education Bureau of the Hong Kong SAR Government, and the Hong Kong Academy of Gifted Education (HKAGE). The UETPS program promotes electrical, electronic, and computer engineering education in Hong Kong and is aimed particularly at gifted students as well as their parents, teachers, and schools. Project applicants underwent formal identification procedures by the Gifted Education Section of the HKSAR Education Bureau and were identified as being gifted in the area of science and technology. Selected participants then participated in one-year research projects in electronics and computer engineering under the guidance of university professors in their respective engineering departments. This program addresses an urgent need of the engineering education sector by reaching out to highly talented K-12 students and their surrounding communities. According to the evaluation results, the UETPS program has significantly enhanced the participating students' interest in engineering as a career choice and encouraged them to pursue undergraduate studies in engineering. This article also discusses lessons learned and proposes strategies for future potential implementers. (Contains 3 tables and 5 figures.)

The interleaved converter topology has attractive features that include high output current, small output-current ripple, and fast transient response. In this paper, an interleaved four-phase forward converter using an integrated transformer is proposed for telecommunication and computer applications. The proposed converter requires only one integrated transformer instead of four step-down transformers. The z-parameter (gyrator) model and the equivalent-circuit model of the integrated transformer are derived. The circuit operation and design criteria are described. Theoretical analyses are verified by simulated and experimental results. Index Terms--Converter with small output-current ripple, integrated magnetics, integrated transformer, interleaved four-phase forward converter, regenerative LC snubber circuit.

A hot swap of power modules is required by high-availability parallel power module systems. With the hot-swappable paralleled power modules, the system up-time can be maximized, the system maintenance and repair can be simplified, and the system upgrade can be allowed for. In this paper, a simple hot-swap solution is proposed for the paralleled power modules which use current-sharing (CS) interface circuits to do the CS work. By redesigning the basic function circuits of the CS interface circuits [4] (such as the under voltage protection circuit, the current-sharing circuit, and the light load protection circuit etc.), an additional hot-swap function can be implemented 'parasitically.' There is no extra hot-swap controller and no compatibility problem between the hot-swap and CS solutions used. A prototype CS interface circuit with a 'parasitic' hot-swap function was designed, implemented, and tested. The results show that the proposed hot-swap solution is feasible and suitable. Index Terms--Current-sharing (CS) interface circuit, hot swap, paralleled power module.

An interleaved three-phase forward converter using an integrated transformer is proposed in this paper. This type of converter has the attractive features of flexible voltage conversion ratio, high output current (due to the parallel connection of outputs), near-zero output-current ripple (due to the output-current-ripple cancellation), fast transient response (due to the small effective output-filtering inductance), and is particularly suitable for high-output-current and low-output-voltage applications such as telecommunication and computer systems. The integrated transformer of the proposed converter consists of three step-down transformers on a single magnetic core. The z-parameter (gyrator) model and the equivalent-circuit model of the integrated transformer are derived. Based on the equivalent-circuit model, the principle of operation of the proposed converter is explained. The analysis and design criteria of the basic circuit, the operation of the regenerative LC snubber circuit, the simulation, and experimental verification are also described. Index Terms--Integrated magnetics, integrated transformer, interleaved three-phase forward converter.

This paper proposes a current-sharing (CS) circuit for parallel power modules. The interface circuit enables the outputs of independent and nonidentical power modules to equally share the load current in a fault-tolerant oring-connection power supply system. No CS interconnections among the power modules are required. In the proposed interface circuit, the output currents of the parallel power modules are sensed by measuring the inductor voltage drops and controlled in a hysteresis manner. A practical CS interface circuit is implemented. The experimental results are in good agreement with the theoretical analyses. Index Terms--Current-sharing (CS) interface circuit, parallel power modules (PPMs).

A three-phase interleaved continuous-inductor-current-mode (CICM) boost converter with zero diode reverse-recovery loss is proposed. In the converter, the di/dt of the output rectifiers is controlled by an integrated magnetic component. All the output rectifiers can be turned off softly and a very high efficiency is obtained. The equivalent-circuit model of the integrated inductors, the operation principle of the converter, and the design issues are discussed. Simulation and experimental results are presented.

An interleaved two-phase forward converter using an integrated magnetic component is proposed for telecommunication and computer applications. The integrated magnetic component consists of two step-down transformers and two output-filtering inductors on a single magnetic core. The z-parameter (gyrator) model and the equivalent-circuit model of the integrated magnetic component are presented. The circuit operation and design criteria of the proposed converter are described. All theoretical analyses are verified by simulated and experimental results.

A single-switch continuous-conduction-mode boost converter with reduced reverse-recovery and switching losses is proposed. By utilizing the leakage inductances of a pair of coupled inductors and two additional rectifiers, the turn-off rates (di/dt) of the boost output rectifier and the additional rectifiers are slowed down to reduce the reverse-recovery loss. The boost power transistor is also operated under a low-voltage turn-on condition to reduce the switching loss. Experimental results are presented to confirm the theoretical analysis and the performance of the proposed converter. Index Terms--Boost converter, continuous conduction mode (CCM), low-voltage turn-on, reverse-recovery loss.

We introduce a method to use z parameters to model the interface between an electric circuit and a magnetic component. With this model, the electrical equivalent circuit of any complex integrated magnetic component can be developed easily. We describe the simulation and design of integrated magnetics using a z-parameter two-port network model. We use a single-switch regulator with power-factor-correction and a single integrated magnetic component as an example to demonstrate the practical applications of integrated magnetics in modern power converters. For the same example, we analyze the problem of uneven magnetic flux density in an integrated magnetic component and propose a possible solution to the problem. Index Terms--Integrated magnetics, modeling of magnetic components, simulation of integrated magnetics.

A new design and fabrication method for planar windings with multilayers is presented. This method can virtually eliminate external soldering or conductive vias, thus reducing dc resistance and increasing reliability. Compared to the previously reported folding methods for winding fabrication, this method maximizes the use of the window height and minimizes the waste of copper area in manufacturing. The winding pattern is cut using a computer numerically controlled machine, or the punching/pressing process, which is cleaner than the commonly used etching process. The whole winding assembly is completed by a folding process. The primary and secondary windings in a transformer can be interleaved, resulting in low leakage inductance. Practical examples of low-profile transformers and inductors were constructed and tested in an active-clamped forward dc-dc converter with self-driven synchronous rectifiers. Experimental results are presented to show that such transformers/inductors are particularly useful for the design of low-profile and high-power density converter modules. Index Terms - Geometry, planar windings, transformer windings, z-folding.

An interleaved three-phase forward converter using an integrated transformer is proposed in this paper. This type of converter has the attractive features of flexible voltage conversion ratio, high output current (due to the parallel connection of outputs), near-zero output-current ripple (due to the output-current-ripple cancellation), fast transient response (due to the small effective output-filtering inductance), and is particularly suitable for high-output-current and low-output-voltage applications such as telecommunication and computer systems. The integrated transformer of the proposed converter consists of three step-down transformers on a single magnetic core. The z-parameter (gyrator) model and the equivalent-circuit model of the integrated transformer are derived. Based on the equivalent-circuit model, the principle of operation of the proposed converter is explained. The analysis and design criteria of the basic circuit, the operation of the regenerative LC snubber circuit, the simulation, and experimental verification are also described. [ABSTRACT FROM AUTHOR]

Introduces the use of z parameters to model the interface between an electric circuit and a magnetic component. Description of simulation and design of integrated magnetics using a z-parameter two-port network model; Demonstration of the practical applications of integrated magnetics in modern power converters; Analysis of the problem of uneven magnetic flux density in an integrated magnetic component.