The present work describes the development of a control scheme for boost-type switch-mode rectifiers. While controllers for this circuit commonly use a shunt resistor or a magnetic field sensor to measure the instantaneous input or inductor current, here the inductor current is computed from the measured inductor voltage. This calculation requires knowledge of the physical properties of the inductor, most importantly its inductance, which are prone to change with operating conditions of the converter and throughout the lifetime of the inductor. The parameters of the inductor model are estimated during normal converter operation, and the inductor model is adapted accordingly. Simulation and experimental results confirm the effectiveness of the devised scheme in reducing the distortion of the input current. / Graduate / 0544 / aengel@uvic.ca

The present work describes the development of a control scheme for boost-type switch-mode rectifiers. While controllers for this circuit commonly use a shunt resistor or a magnetic field sensor to measure the instantaneous input or inductor current, here the inductor current is computed from the measured inductor voltage. This calculation requires knowledge of the physical properties of the inductor, most importantly its inductance, which are prone to change with operating conditions of the converter and throughout the lifetime of the inductor. The parameters of the inductor model are estimated during normal converter operation, and the inductor model is adapted accordingly. Simulation and experimental results confirm the effectiveness of the devised scheme in reducing the distortion of the input current. / Graduate / 0544 / aengel@uvic.ca

This thesis is a feasibility study for a manipulator for an automated assembly of inductors for the automotive industry. Firstly there is an analysis of the current production status. Secondly there is a proposed concept for mechanical, electrical and pneumatic parts of such a machine. Next is the description of the production and completion of the manipulator. And the final part deals with the implementation of this device.

Multiphase interleaving buck converters are widely used in today's industrial point-of-load (POL) converters, especially the microprocessor voltage regulators (VRs). The issue of today's multiphase interleaving buck converters is the conflict between the high efficiency and the fast transient in the phase inductor design. In 2000, P. Wong proposed the multiphase coupledinductor buck converter to solve this issue. With the phase inductors coupled together, the coupled-inductor worked as a nonlinear inductor due to the phase-shifted switching network, and the coupled-inductor has different equivalent inductances during steady-state and transient. One the one hand, the steady state inductance is increased due to coupling and the efficiency of the multiphase coupled-inductor buck converter is increased; on the other hand, the transient inductance is reduced and the transient performance of the multiphase coupled-inductor buck is improved. After that, many researches have investigated the multiphase coupled-inductor buck converters in different aspects. However, there are still many challenges in this area: the comprehensive analysis of the converter, the alternative coupled inductor structures with the good performance, the current sensing of converter and the light-load efficiency improvement. They are investigated in this dissertation. The comprehensive analysis of the multiphase coupled-inductor buck converter is investigated. The n-phase (n>2) coupled-inductor buck converter with the duty cycle D>1/n hasn't been analyzed before. In this dissertation, the multiphase coupled-inductor buck converter is systematically analyzed for any phase number and any duty cycle condition. The asymmetric multiphase coupled-inductor buck converter is also analyzed. The existing coupled-inductor has a long winding path issue. In low-voltage, high-current applications, the short winding path is preferred because the winding loss dominates the inductor total loss and a short winding path can greatly reduce the winding loss. To solve this long winding path issue, several twisted-core coupled-inductors are proposed. The twisted-core coupled-inductor has such a severe 3D fringing effect that the conventional reluctance modeling method gives a poor result, unacceptable from the design point of view. By applying and extending Sullivan's space cutting method to the twisted core coupled inductor, a precise reluctance model of the twisted-core coupled-inductor is proposed. The reluctance model gives designers the intuition of the twisted-core coupled-inductors and facilitates the design of the twisted-core coupled-inductors. The design using this reluctance model shows good correlation between the design requirement and the design result. The developed space cutting method can also be used in other complex magnetic structures with the strong fringing effect. Today, more and more POL converters are integrated and the bottleneck of the integrated POL converters is the large inductor size. Different coupled-inductor structures are proposed to reduce the large inductor size and to improve the power density of the integrated POL converter. The investigation is based on the low temperature co-fire ceramic (LTCC) process. It is found that the side-by-side-winding coupled-inductor structure achieves a smaller footprint and size. With the two-segment B-H curve approximation, the proposed coupled-inductor structure can be easily modeled and designed. The designed coupled-inductor prototype reduces the magnetic size by half. Accordingly, the LTCC integrated coupled-inductor POL converter doubles the power density compared to its non-coupled-inductor POL counterpart and an amazing 500W/in³ power density is achieved. In a multiphase coupled-inductor converter, there are several coupled-inductor setups. For example, for a six-phase coupled-inductor converter, three two-phase coupled inductors, two three-phase coupled-inductors and one six-phase coupled inductors can be used. Different coupled-inductor setups are investigated and it is found that there is a diminishing return effect for both the steady-state efficiency improvement and the transient performance improvement when the coupling phase number increases. The conventional DCR current sensing method is a very popular current sensing method for today's multiphase non-coupled-inductor buck converters. Unfortunately, this current sensing method doesn't work for the multiphase coupled-inductor buck converter. To solve this issue, two novel DCR current sensing methods are proposed for the multiphase coupled-inductor buck converter. Although the multiphase coupled-inductor buck converters have shown a lot of benefits, they have a low efficiency under light-load working in DCM. Since the DCM operation of the multiphase coupled-inductor buck converter has never been investigated, they are analyzed in detail and the reason for the low efficiency is identified. It is found that there are more-than-one DCM modes for the multiphase coupled-inductor buck converter: DCM1, DCM2 …, and DCMn. In the DCM2, DCM3 …, and DCMn modes, the phase-currents reach zero-current more-than-once during one switching period, which causes the low efficiency of the multiphase coupledinductor buck converter in the light load. With the understanding of the low efficiency issue, the burst-in-DCM1-mode control method is proposed to improve the light load efficiency of the multiphase coupled-inductor buck converter. Experimental results prove the proposed solution. / Ph. D.

The emerging need for smart and wearable electronic systems are driving new electronics technology paradigms in miniaturization, functionality and cost.The operating voltages and power levels for devices in these systems are becoming increasingly varied with increased diversity of devices to serve these heterogeneous functions. Power convertor technologies are incorporated into various parts of these systems to step-up or step-down battery voltages and currents to address these diverse needs. Hence, multiple power converters, each requiring several passive components, are used to create stable power-supplies. This is placing significant challenges in ultra-miniaturized and ultra-efficient power management technologies. A typical power convertor consists of magnetic components such as inductors perform the basic energy storage and delivery functions from the source to the load. These power components are still at microscale in lithography and milliscale in component size. They occupy a large volume fraction of the power circuitry. Power convertors therefore, are a major bottleneck to system miniaturization. There is, thus, a need for ultra-miniaturized and high-performance power inductors for scaling down such power convertors. The critical parameters governing the size and performance of power inductors are its inductance density and power handling capability. These parameters are limited by the magnetic properties of the present inductor core materials. A new approach to inductor cores that achieves the best magnetic properties and yet allows integration of power inductors into ultra-thin substrates to meet the emerging needs for performance and size is therefore required. The objective of this research is to model, design and synthesize a novel multilayered ferromagnetic-polymer composite structure for inductor cores with high permeability and saturation magnetization.The multilayered composite structure consists of thin magnetic layers interspersed with ultra-thin polymers. A fabrication approach to integrate the composite structure in inductor devices is also demonstrated.

This paper is the use of the active inductor instead of passive inductors to save area, enter the match aspects of the use of the feedback capacitor in parallel with the resistor to achieve matching with the control input voltage, in addition to adjusting the feedback resistor can control the noise. The LNA dissipates 13.2 mW power and achieves input return loss (S11) below -10dB, output return loss (S22) below -10 dB, forward gain (S21) of 11.3~14.5dB, reverse isolation (S12) below -40dB, and noise figure (NF) of 3~3.18 dB. 1-dB compression point (P1dB) of -24 dBm and input third-order inter-modulation point (IIP3) of -14 dBm .

In this paper we describe an approach to generating low-order models of spiral inductors that accurately capture the dependence on both frequency and geometry (width and spacing) parameters. The approach is based on adapting a multiparameter Krylov-subspace based moment matching method to reducing an integral equation for the three dimensional electromagnetic behavior of the spiral inductor. The approach is demonstrated on a typical on-chip rectangular inductor. / Singapore-MIT Alliance (SMA)

A theoretical approach to calculating impedance of metallicmagnetic/conductor layered structures is developed. Thefrequency range considered extends to the ferromagneticresonance region of soft magnetic films (of the order of 1GHz). The analysis includes the effects of screening of thehigh frequency fields by eddy currents as well as the dynamicsand relaxation of the magnetization of the ferromagneticsub-system. Analytical expressions for the impedance as afunction of frequency and material parameters and geometry ofmagnetic sandwich stripes are obtained. Two maincross-sectional layouts are considered: amagnetic/conductor/magnetic sandwich stripe with and withoutflux closure at the edges along the stripe length - with andwithout the magnetic film enclosing the conductor strip. Theimportance of good magnetic flux closure for achieving largespecific inductance gains and high efficiency at GHzfrequencies is emphasized. The theoretical results obtained were used to design andanalyze magneticfilm inductors produced using iron nitridealloy films. Patterned sandwiches, consisting of two Fe-N filmsenclosing a conductor film made of Cu, were fabricated onoxidized Si substrates using lift-off lithography. Theinductors exhibited a 2-fold specific inductance enhancement at1 GHz. The magnetic contribution to the total flux in thenarrow devices was less then predicted theoretically, which wasattributed to hardening of the magnetic material at the edgesof the strip leading to incomplete flux closure. Material anddesign issues important for further improving the performanceof the devices are discussed.

The suitable frequency range of electromagnetic interference (EMI) filters is always limited by the parasitic inductances and capacitances of components. The main object in this research is to develop design rules for lowering parasitic effects due to parasitic inductance of capacitor by using three coupled inductors. In this thesis, the properties and equivalent circuit of three coupled inductors are discussed first. It is found that two negative series inductances can be simultaneously obtained at two ports when the parameters of three coupled inductors are appropriately selected. These two negative inductances can be used to lower parasitic effect of capacitors. In other words, the EMI filter performance can be effectively improved by using this technology. Furthermore, method to completely reduce parasitic inductances is derived. The common mode insertion loss of this design is able to achieve at the rate of -60 dB/decade at high-frequency. For differential mode the insertion loss is even higher to the rate of -100 dB/decade.

This project focusses on the design of a high speed passive delay line for use in a Feed Forward Equalizer (FFE). The FFE is used to equalize a 20 Gbp/s throughput PAM-4 signal after transmission through a 20-inch FR4 backplane channel. Inductor electromagnetic simulations are used to design an inductor for use in the passive delay line and a lumped element inductor model is presented. Measurement results show performance of the delay line at 10 GSym/s.