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This paper aims to propose an efficient model for analysis of power electronic circuits with integrated magnetic components.

The inductance modeling technique is used as the traditional method for analyzing magnetic components. This model is simple and enough to generate for individual components, that is, an inductor and a transformer. However, it becomes difficult to realize this model for the integrated magnetic structures. This paper shows an appropriate model for individual magnetic components as well as integrated magnetic components and its application to magnetically coupled DC–DC converters. Gyrator–capacitor (G–C) modeling offers a unified, reasonable way of understanding the magnetic components commonly met with in power electronics and the other disciplines.

G–C model allows any electrical and magnetic circuit to be simultaneously simulated with circuit simulators. In this regard, this paper gives a complete simulation model and analysis as an illustrative example. There is no limitation of this paper or future works. The proposed G–C model can be applied to all power electronic circuits having integrated magnetic components.

In the proposed model, the magnetic circuit is converted to a pure electric circuit with capacitors and controlled sources; every winding is replaced with a pair of current controlled voltage sources, namely, a gyrator.

The purpose of this research paper is to explore the possibility to enhance the power transfer from piezoelectric energy harvester (PEH) source to the load. As the proposed gyrator-induced voltage flip technique (GIVFT) does not require bulky components such as physical inductors, it is easily realizable in small integrated circuits (IC) package thereby offering performance benefits, reducing area overhead and providing cost benefits for constrained self-powered autonomous Internet-of-Things (IoT) applications.

This paper presents an inductorless interface circuit for PEH. The proposed technique is called GIVFT and is demonstrated using active elements. The authors use gyrator to induce voltage flip at the output side of PEH to enhance the charge extraction from PEH. The proposed technique uses the current-voltage (I-V) relationship of gyrator to get appropriate phasor response necessary to induce the voltage flip at the output of PEH to gain power transfer enhancement at the load.

The experimental results show the efficacy of the GIVFT realization for enhanced power extraction. The authors have compared their proposed design with popular earlier reported interface circuits. Experimentally measured performance improvement is 1.86×higher than the baseline comparison of full-wave bridge rectifier circuit. The authors demonstrated a voltage flip using GIVFT to gain power transfer improvement in piezoelectric energy harvesting.

To the best of the authors’ knowledge, pertaining to the field of PEH, this is the first reported GIVFT based on the I-V relationship of the gyrator. The proposed approach could be useful for constrained self-powered autonomous IoT applications, and it could be of importance in guiding the design of new interface circuits for PEH.

To solve the problem of meminductor in circuit design, this paper aims to describe a synthesis method and the mechanism in terms of constitutive relation of the gyrator for transforming nano memristor into meminductor.

The gyrator was designed to achieve memristor-meminductor transformation by using amplifiers and memristor.

The simulation results verify the flexibility of its operation.

This gyrator can be used in integrated circuit design such as filter, diplexer, and it has a simple and economical implementation.

The paper presents a method of creating electrical equivalent diagrams of magnetic circuits. The method is based on bond‐graph techniques, using flux derivative as flow variable. Couplings between magnetic and electric part of the system are represented by gyrators. Simple models of magnetic branches, including non‐linear effects due to saturation, hysteresis and eddy currents, are presented. These models can be easily combined into magnetic circuit models, which can be transformed into dual electric equivalent circuit. Various equivalent circuits of transformers are discussed. The proposed models are simple and particularly useful for system‐level simulation of power electronic and motion control systems with magnetic elements. These models can be easily developed if needed. Theoretical considerations are illustrated by examples of digital simulation and experimental results.

The purpose of this paper is to investigate the applicability of a direct current (DC) hysteresis measurement on power transformer terminals for the subsequent hysteresis model parametrization in transformer grey box topology models.

Two transformer topology models with two different hysteresis models are used together with a DC hysteresis measurement via the power transformer terminals to parameterize the hysteresis models by means of an optimization. The calculated current waveform with the derived model in the transformer no-load condition is compared to the measured no-load current waveforms to validate the model.

The proposed DC hysteresis measurement via the power transformer terminals is suitable to parametrize two hysteresis models implemented in transformer topology models to calculate the no-load current waveforms.

Different approaches for the measurement and utilization of transformer terminal measurements for the hysteresis model parametrization are discussed in literature. The transformer topology models, derived with the presented approach, are able to reproduce the transformer no-load current waveform with acceptable accuracy.

This paper aims to improve the fault detection adaptive threshold of aircraft flap control system to make the system fault diagnosis more accurate.

According to the complex mechanical–electrical–hydraulic structure and the multiple fault modes of the aircraft flap control system, the advanced fault diagnosis method based on the bond graph (BG) model is presented, and based on the system diagnostic BG model, the parameter uncertainty intervals are estimated and a new adaptive threshold is constructed by linear fraction transformation.

To construct a more reasonable and accurate adaptive threshold range to more accurately detect system failures, some typical failure modes’ diagnosis process are selected and completed for verification; the simulation results show that the proposed method is effective and feasible for complex systems’ fault diagnosis.

This study can provide a theoretical guidance and technical support for fault diagnosis of complex systems, which avoid misdiagnosis and missed diagnosis.

This study enables more accurate fault detection and diagnosis of complex systems when considering factors such as parameter uncertainty.

Stranded on a desert island or in a hospital bed with only one book to read, the victim can do far worse than have a good dictionary on his favourite subject. You flick over the pages to look up something you want to know, your eye catches an adjacent entry which intrigues you and you are off on the fascinating game of being referred from one entry to another in your pursuit of knowledge. If the game is not to lead to frustration and anger the book must play fair by you, it must leave you with the feeling that you have really learnt something for your efforts, even if occasionally this is that the subject is too abstruse for concise treatment and you are fobbed off with a list of references.

Examines the product design and manufacturing literature to understand why consumer products of daily use often fail to provide the intended function to users’ satisfaction. The review shows that the bulk of published literature addressing functionality and functional representation deals with mechanical systems design, and there are issues that directly affect the consumer that are yet to be accommodated in current research in functional representation. The literature also reveals that very few of the product design support systems have been tested on real design cases, or have been developed and tested using real designers in manufacturing environments – this issue needs serious consideration if efficient designer aids are to be developed in the future. Also, there is relatively little that has been done to develop tools to evaluate alternative design solutions. It is also apparent from this review that the main research focus has been on providing function, rather than on ensuring function in a product that is eventually manufactured.

Pipeline robots are often used in pipeline non-destructive testing. Given the need for long-range in-pipe inspections, this study aims to develop a wireless in-pipe inspection robot for image acquisition.

In this paper, an in-pipe robot with a new mechanical system is proposed. This system combines a three-arm load-bearing structure with spring sleeves and a half-umbrella diametric change structure, which can ensure the stability of the camera when acquiring images while maintaining the robot’s flexibility. In addition, data were transmitted wirelessly via a system that uses a 433 MHz ultra-high frequency and wireless local-area network–based image transmission system. Software and practical tests were conducted to verify the robot’s design. A preliminary examination of the robot’s cruising range was also conducted.

The feasibility of the robot was demonstrated using CATIA V5 and MSC ADAMS software. The simulation results showed that the centre of mass of the robot remained in a stable position and that it could function in a simulated pipeline network. In the practical test, the prototype functioned stably, correctly executed remote instructions and transmitted in near real-time its location, battery voltage and the captured images. Additionally, the tests demonstrated that the robot could successfully pass through the bends in a 200-mm-wide pipe at any angle between 0° and 90°. In actual wireless network conditions, the electrical system functioned for 44.7 consecutive minutes.

A wheeled wireless robot adopts a new mechanical system. For inspections of plastic pipelines, the robot can adapt to pipes with diameters of 150–210 mm and has the potential for practical applications.