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The purpose of this paper is to develop a model of the inductive link for implantable systems. The model is suitable for a cochlear implant in which a lateral misalignment and distance coil can be up to 16 mm.

The description of the generation of implantable systems' high‐power, such as a cochlear implant, are powered by transcutaneous inductive power links formed by two coils: the first is a printed spiral coil used in the receiver device and the second is a solenoid coil used in the emitter device. Optimizing the power efficiency of the wireless link is imperative to minimize the size of the external energy source, heating dissipation in the tissue, and interference with other devices. The authors have outlined the theoretical foundation of optimal power transmission efficiency in an inductive link, and combined it with semi‐empirical models to predict parasitic components. The power amplifier itself is a class‐E amplifier optimized in both output voltage and efficiency, and bears an excellent tolerance to misalignments.

Two Spice‐based electrical models of the coils are achieved. The technique employed during the work is based on polynomial interpolation of the mutual inductance in which coil misalignments are considered as variables. On the other hand, a voltage regulator is studied and simulated by Cadence Analog Artist in the AMS 0.35 μm CMOS technology.

This paper provides a novel and useful method for transmitting power for an implantable system via an inductive link. The procedure of the authors' design is achieved at 10 MHz and the power transmission efficiency is 35 percent, whatever the longitudinal misalignment (up to 16 mm) between both coils.

The purpose of this paper is to devote the optimal substitution of slip rings through an inductive power transfer system for field winding supply of generators or motors with a wound rotor. By a rotational pot-core transformer approach, the rotor-side energizing of the excitation windings can be provided isolated and free of wear.

For design purpose, an analytical model of the inductive link and the compensation network elements is shown. Based on a pot-core transformer approach, possible types of compensation networks regarding motor-specific constraints were carried out and compared among themselves by parameter studies. The analytical parts of the model were subsequently validated with measured data of an appropriate core and accompanying FEM calculations. On the basis of an experimental prototype system, the approach has been tested both stationary and transient.

The publication exemplifies how a brushless excitation system for generators and motors can be inexpensively designed and implemented.

This paper systematically presents a comprehensive analytical approach for brushless excitation systems as well as a prototypical system. Compensation network elements regarding motor-specific constraints were carried out and compared among themselves by parameter studies.

The purpose of this paper is to present the design and the numerical calculation of the electromagnetic heating system for the ablation therapy. Hence, the heating of the tumor cells must be processed very carefully to achieve a localized coagulative necrosis and to avoid too high temperatures inside the tissue.

The non-invasive method of the ablation therapy is implemented due to the inductive power transmission between the generator and implant. The ferromagnetic implant has a small size and can be placed intravenously into tumor cells. High-frequency driving currents are necessary to obtain high induced eddy currents within the ferromagnetic implant.

Finite element analysis has been used for the design and numerical calculation of the electromagnetic heating system. The electromagnetic analysis is done in the time domain due to the nonlinearity of the ferromagnetic implant. Magnetic fields are computed based on a magnetic vector potential formulation. The thermal analysis is done in the time domain as well. The temperature computation in biological tissue is based on a heat balance equation.

This paper is focused on the design and simulation of the inductive system for the ablation therapy.

The designed system can be practically implemented. It can be used for the clinical study of the immune response by the thermal ablation therapy.

The common method of thermal ablation is combined with an inductive power transmission. It enables a repetitive application of this method to study the immune response.

This paper aims to analyze the frequency characteristics of wireless power transfer (WPT) systems with relay resonators in terms of the power delivered to the load and system efficiency. Based on the analytical results, system parameters can be optimized to achieve maximum power transfer and higher system efficiency.

Based on Kirchhoff’s voltage law equations, WPT systems with relay resonators are described by the coupled linear second-order differential equations. Splitting frequencies are estimated by using the matrix theory. In addition, critical coupling conditions are demonstrated based on discriminant analysis.

It was found that multi-maximum values exist for the power delivered to the load and total system efficiency owing to multiple eigenfrequencies of the system. Also, frequency conditions of maximum power transfer and system efficiency, as well as their critical coupling conditions, were quantitatively estimated.

During our analytical process, we assume that quality factors of resonators in the system are high and the crossing coupling between resonators is negligible.

In previous works, the exact analysis of frequency characteristics is limited to WPT systems with two resonators. The appealing feature of this work lies in its ability to present a simplified analytical method with negligible approximation errors for WPT systems with relay resonators.

The purpose of this paper is to present the stages for manufacturing a low‐cost miniaturized prototype device, which observes the restrictions of implantable medical devices. The device measures the electrocardiography. The power for the implant is received passively as the same magnetic field as data is transferred to the reader device.

In this manufacturing technique, only easily attachable commercial available components are used, etching is used to simply produce a low‐cost double‐sided flexible printed circuit board which is converted to 3D by folding.

The circuit board was folded into the final shape after component attachment and the final result was a compact 3D package within the specifications determined by the electronics designer. The miniaturized prototype device was successfully tested both in vitro and in vivo.

The manufacturing technique of the sensing device can be readily adapted to other devices that need to be miniaturized. The coatings used for electrical insulation and chemical protection and the type of adhesives used for folded packages are easily utilized in similar miniaturization prototypes. By using bare chips, the final product would have been even smaller but for prototyping it is cheaper and faster to use easily acquired and attached components. In the case of mass production, the whole new design, where bare chips with flip chip attachments, integrated passives and/or stacked 3D packages with design considerations such as electrical, thermal and mechanical engineering is justified.

The purpose of this paper is to present a method to calculate the transient induced voltages along the underground pipelines and analyze the transient interference generated in the pipelines due to the inductive coupling in the fault‐to‐ground condition of power lines in close proximity.

Based on finite difference‐time domain method, an improved method is proposed to calculate transient inductive interference in underground metallic pipelines due to a fault in nearby power lines. The frequency‐dependent problem in the analysis of transient interference is solved in phase domain. Compared with the traditional method, the disposal of phase‐modal transformation matrices’ frequency‐dependent characteristic is avoided and the calculation is simplified by using vector fitting approach and recursive algorithm greatly in the proposed method.

A novel improved method is proposed to calculate transient induced voltage distribution along underground metallic pipelines due to a fault in nearby power lines. Results show that the peak value of transient induced voltage at the most critical point is about 1.15 times of the magnitude in the steady state without the fault removed and the analysis of transient inductive interference is necessary in the fault‐to‐ground case of power lines.

In order to mitigate the interference from power lines to nearby pipelines, pipelines should be good grounded and positioned as far away from the power line as possible. In high soil resistivity areas, the common corridor should be avoided.

The paper presents a method to calculate the transient induced voltages along the underground pipelines and analyze the transient interference generated in the pipelines due to the inductive coupling in the fault‐to‐ground condition of nearby power lines. The proposed method is general and can also be applied to other transient interference studies such as crosstalk problems of communication networks and interference between power lines and aboveground pipelines or communication cables. Effects of various parameters upon the inductive interference generated in underground pipelines due to a fault in nearby power lines are analyzed to be a guide for controlling the inductive interference.

The performance of a high‐speed chip is highly dependent on the interconnects, which connect different macro cells within a VLSI chip. Delay, power dissipation and cross‐talk are the major design constraints for high performance VLSI interconnects. The importance of on‐chip inductance is continuously increasing with higher clock frequency, faster on‐chip rise time, wider wires, ever‐growing length of interconnects and introduction of new materials for low resistance interconnects. In the current scenario, interconnect is modeled as an RLC transmission line. Interconnect width optimization plays an important role in deciding transition delay and power dissipation. This paper aims to optimize interconnect width for a matched condition to reduce power and delay parameters.

Width optimization is done for two sets of interconnect terminating conditions, namely active gate and passive capacitance. SPICE simulations have been used to validate the findings.

For a driver interconnect load model terminated by an active gate load, a trade‐off exists between short circuit and dynamic power in inductive interconnects, since with wider lines dynamic power increases, but short circuit power of the load gate decreases due to reduced transient delay. Whereas, for a line terminated by a capacitor, such trade‐off does not exist. Many of the previous researches have modeled the active gate load at the terminating end by its input parasitic gate capacitance.

This paper shows that such modeling leads to inaccuracy in estimation of power, and therefore non‐optimal width selection, especially for large fan‐out conditions.

The finding is that the impedance matching between transmission line at driver and load ends plays an important role in estimation of overall power dissipation and transition delay of a VLSI circuit.

To analyze factors affecting crosstalk and to study the effect of repeater insertion on crosstalk, power dissipation and propagation delay.

Crosstalk is effected by transition time of the signal; length of interconnect; distance between interconnects; size of driver and receiver; pattern of input; direction of flow of signal; and clock skew. This work is based on simulating interconnects with parameters obtained from 0.13 μm process. The types of noise addressed are overshoot; undershoot and oscillatory noise. Further, to study the effect of repeater insertion on crosstalk, repeaters are inserted in one line, i.e. line A only. Uniform repeaters varying in number from 1 to 60 are each of size W_n=3.9 μm and W_p=7.8 μm. Both lines A and B are terminated by a capacitive load of 5 fF. A crosstalk noise effect is measured for line A loaded with repeaters. The number of repeater is varied for four different cases of stimulations to both lines viz. input to line A, i.e. V_A switching from low to high; input to line B, i.e. V_B switching from low to high; input to line A i.e V_A switching from low to high; input to line B, i.e. V_B switching from high to low; V_A switching from high to low and V_B at static low; V_A switching from high to low and V_B at static high.

This paper shows the prominent factors such as edge rate, length and pattern of inputs affecting the noise. It is observed that presence of inductive effects can seriously hamper the functioning of the chip. This paper further reveals that repeater insertion not only reduces the propagation delay but also crosstalk levels for coupled lines. Repeaters can be efficiently utilized for reduction of propagation delay and crosstalk noise at a trade of marginal increase in power dissipation. The power‐delay‐crosstalk‐product (PDCP) criterion is introduced as an efficient technique to insert repeater in coupled interconnects. Based on PDCP a reduction in crosstalk of about 60 times and delay of 4.2 percent is achieved at trade of 13.2 percent increase in power dissipation in comparison to PDP.

The PDCP criterion is introduced as an efficient technique to insert repeater in coupled interconnects. Instead of PDP criterion, PDCP criterion is best suited for determination of optimum number of repeaters for overall minimization of delay, power and crosstalk.

The purpose of this paper is to model and analyze energy transfer through near‐field resonant coupling for high power light‐emitting diode (HPLED) illumination, with the intention to increase the appreciation and use of the coupled mode theory (CMT) other than the usual equivalent circuit method.

The CMT is extensively used to analyze the wireless energy transfer system because of its generality, simplicity, accuracy and intuitive understanding of near‐field resonant energy coupling mechanism.

The CMT forms a general way to model and analyze the non‐radiative magnetic resonant coupling systems. It is suitable not only for low frequency coupling but also for high frequency (of million‐Hertz) in which the circuit parameters are not easily obtained. Optimal coupling condition corresponding to the maximum power transfer is identified based on the CMT, and the multiple limit cycle phenomenon caused by the nonlinear nature of the HPLED is also described on the CMT model.

This paper takes advantages of CMT, i.e. generality, simplicity, accuracy and intuitive understanding to analyze the near‐field resonant energy coupling system. Key characteristics of the systems are explored based on the CMT, not the usual equivalent circuit method. The influence of nonlinear nature of the high power LED on energy transfer is also investigated. This work seeks a more general way than conventional equivalent circuit method to model and analyze the resonant magnetic system and the results obtained could facilitate better understanding of the resonant magnetic coupling mechanism and optimal design of the near‐field energy transfer system.

Efficient calculations of the transient behaviour after disturbances of large-scale power systems are complex because of, among other things, the non-linearity and the stiffness of the overall state equation system (SES). Because of the rising amount of flexible transmission system elements, there is an increasing need for reduced order models with a negligible loss of accuracy. With the Extended Nodal Approach and the application of the singular perturbation method, it is possible to reduce the order of the SES adapted to the respective setting of the desired tasks and accuracy requirements.

Based on a differential-algebraic equation for the electric power system which is formulated with the Extended Nodal Approach, the automatic decomposition into reduced order models is shown in this paper. The paper investigates the effects of different coordinate systems for an automatic order reduction with the singular perturbation method, as well as a comparison of results calculated with the full and reduced order models.

The eigenvalues of the full system are approximated sufficiently by the three subsystems. A simulation example demonstrates the good agreement between the reduced order models and the full model independent of the choice of the coordinate system. The decomposed subsystems in rotating coordinates have benefits as compared to those in static coordinates.

The paper presents a systematic decomposition based only on a differential-algebraic equation system of the electric power system into three subsystems.