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This paper presents a three-phase voltage-source 36-pulse converter that draws almost sinusoidal currents. The converter results from the combination of a series-connected 12-pulse voltage-source rectifier with a passive voltage-injection circuit and a bidirectional switch, referred to as hybrid injection. The voltage-injection circuit uses a single-phase rectifier bridge and a single-phase transformer. Both the voltage-injection circuit and the bidirectional switch operate at six times the supply frequency and have a low rating. In this paper, the converter operation is explained and analyzed. Subsequently, the converter is evaluated experimentally using a 4-kW 400-Hz prototype, where the [THD.sub.I] of the line currents was measured to be below 1.2%. Index Terms--AC-DC power conversion, aircraft power systems, power quality, rectifiers.

A sample-data modeling strategy for a 30-kW, two-phase dual interleaved buck–boost converter with peak current control is analyzed in this article. A small-signal converter model is derived to characterize the system utilizing the current peaks of the two interleaved phases and a half-symmetry, state-space representation of the circuit. The model is experimentally verified using a 32-kW, 350-V prototype that owns 7.6 kW/kg and 97.1% of power density and efficiency, respectively. A description of the controller, developed in a high-performance microcontroller, is also presented together with the experimental verification, detailing the design of the compensating ramp for a wide load range. Measured results are contrasted with the sample-data model predictions, using both transient and frequency responses, and evaluating the controlled converter dynamics at 14, 21, 26, and 30 kW. The comparison reveals the effective validity of the presented sample-data model and the effects of the supply to the dynamic performance of the high-density converter. [ABSTRACT FROM AUTHOR]

A three-phase, multilevel rectifier using active voltage injection with one MOSFET device is presented. The injector consists of a bidirectional switch that modifies the behavior of a 12-pulse rectifier resulting in either 24-pulse or multilevel pulsewidth-modulated (PWM) operation. The resultant input currents are almost sinusoidal, the line current THD being 2.36% for 24-pulse operation and 1.06% for PWM operation. The MOSFET current is 2.9% of the load current. The circuit operation, idealized waveforms and modulation strategy are explained and experimental results are presented. Index Terms--High-power factor rectification, three-phase multipulse rectifier.

In power electronics, magnetic components are fundamental, and, unfortunately, represent one of the greatest challenges for designers because they are some of the components that lead the opposition to miniaturization and the main source of losses (both electrical and thermal). The use of ferromagnetic materials as substitutes for ferrite, in the core of magnetic components, has been proposed as a solution to this problem, and with them, a new perspective and methodology in the calculation of power losses open the way to new design proposals and challenges to overcome. Achieving a core losses model that combines all the parameters (electric, magnetic, thermal) needed in power electronic applications is a challenge. The main objective of this work is to position the reader in state-of-the-art for core losses models. This last provides, in one source, tools and techniques to develop magnetic solutions towards miniaturization applications. Details about new proposals, materials used, design steps, software tools, and miniaturization examples are provided. [ABSTRACT FROM AUTHOR]

A two-phase buck–boost converter utilizing dual interleaving is presented in this article. The dual interleaving consists of an interphase transformer (IPT) that doubles the ripple frequency together with two conventional buck–boost switching arms, mitigating the inductor ripple current and aiding to increase the power density of the converter. A description of the design and selection of the power devices is presented for a 32-kW, 75-kHz dual interleaved SiC prototype with an IPT, such that a power density of 7.4 kW/kg is achieved. The operation of the circuit is verified experimentally using a prototype with 315–385 V supply range and 350-V output voltage, achieving 97.1% peak efficiency at 32 kW. The experiments reveal that the interleaved coupled currents are equalized without an active balancer. [ABSTRACT FROM AUTHOR]

The principle of operation of a modular AC-DC converter for Plug in Electric Vehicles (PEV's) battery charger applications is presented. The topology is a split version of a conventional active rectifier in a three-phase matrix converter and an H bridge. A Space Vector Pulse Width Modulation (SVPWM) scheme is used together with a Zero Voltage Switching (ZVS) strategy to reduce the switching loses, output voltage regulation, and a low Total Harmonic Distortion (THD). Simulation results are presented to verify the principle of operation of the AC-DC topology with a 5 kW converter. [ABSTRACT FROM AUTHOR]

Under the unavailability of some components of a complex system, the Hardware In the Loop (HIL) tool allows the emulation of other subsystems. When these devices are not available, a customized emulator can be developed based on the Piecewise Linear Model (PWLM) and a numerical method for solving the differential equations system. However, these implementations require the use of a Field Programmable Gate Array (FPGA) with extensive hardware resources. In this article we propose the use of switching functions for the modeling of power converters of a Hybrid Power System (HPS), allowing the reduction of hardware resources of the FPGA, and the number of steps per switching cycle is increased. The results are compared with SABER simulations and a PWLM evaluated with the Euler method. [ABSTRACT FROM AUTHOR]

This paper reports a new course in power protection and management course for an Electrical Engineering Technology Program at Mohawk College. Motivations, fundamentals and practical recommendations based on inquiry-based model are also covered. [ABSTRACT FROM AUTHOR]

A study of the fundamental of operation of a three-phase AC-DC power converter that uses Zero-Voltage Transition (ZVT) together with Space Vector Pulse Width Modulation (SVPWM) is presented. The converter is basically an active rectifier divided into two converters: a matrix converter and an H bridge, which transfer energy through a high-frequency transformer, resulting in a modular AC-DC wireless converter appropriate for Plug-in Electric Vehicles (PEVs). The principle of operation of this converter considers high power quality, output regulation and low semiconductor power loss. The circuit operation, idealized waveforms and modulation strategy are explained together with simulation results of a 5 kW design. [ABSTRACT FROM AUTHOR]

The realization of an improved predictive current controller based on a trapezoidal model is described, and the impact of this technique is assessed on the performance of a 2 kW, 21.6 kHz, four-wire, Active Power Filter for utility equipment of Metro Railway, Power-Land Substations. The operation of the trapezoidal predictive current controller is contrasted with that of a typical predictive control technique, based on a single Euler approximation, which has demonstrated generation of high-quality line currents, each using a 400 V DC link to improve the power quality of an unbalanced nonlinear load of Metro Railway. The results show that the supply current waveforms become virtually sinusoidal waves, reducing the current ripple by 50% and improving its power factor from 0.8 to 0.989 when the active filter is operated with a 1.6 kW load. The principle of operation of the trapezoidal predictive controller is analysed together with a description of its practical development, showing experimental results obtained with a 2 kW prototype. [ABSTRACT FROM AUTHOR]

This paper presents the development of an experimental B-learning laboratory for an electrical machines undergraduate course. A custom conditioning signal board was developed from scratch that fits a low-cost data acquisition board used to interact with the LabVIEW real time target. In addition a friendly graphical user interface was developed that allows real time remote user interaction. The system was developed and fully tested in a standard Lucas-Nulle 300W electrical machines module. It is shown that the resulting system can be extended to other modules already in the market, and the conditioning signal board adapted to other electrical engineering courses. [ABSTRACT FROM PUBLISHER]

This paper presents an unusual topology of a medium-power seven-level inverter that utilizes a single dc source and a three-phase transformer to generate high-performance seven-level voltage waveforms without complex cascade H-bridges with isolated dc supplies or neutral-point-clamped circuits with capacitor balancing techniques. In contrast to typical topologies of multilevel inverters, the control strategy of the presented circuit facilitates its implementation on a simple 16-bit microcontroller, such that the proposed inverter is operated under a space vector mode. The principle of operation of the seven-level inverter is analyzed, using idealized waveforms for easy and straight implementation together with a description of its practical development, showing experimental results obtained with a 1-kW prototype. [ABSTRACT FROM AUTHOR]

Battery charger is a key device in electric and hybrid electric vehicles. On-board and off-board topologies are available in the market. Lightweight, small, high performance, and simple control are desired characteristics for on-board chargers. Moreover, isolated single-phase topologies are the most common system in Level 1 battery charger topologies. Following this trend, this paper proposes a sampled-data modelling strategy of a zero voltage transition (ZVT) DC-DC converter for an on-board battery charger. A piece-wise linear analysis of the converter is the basis of the technique presented such that a large-signal model and, therefore, a small-signal model of the converter are derived. Numerical and simulation results of a 250Wtest rig validate the model. [ABSTRACT FROM AUTHOR]

Two techniques are presented to balance the filter capacitor voltages of a multipulse rectifier with the active injection operating on a variable-frequency supply. The active injector consists of a low-rated bidirectional switch that modifies the behavior of a 12-pulse rectifier at either low or high frequency, resulting in 24-pulse or multilevel pulse width modulation operation, respectively. The operation of the rectifier and the injector, the practical issues that unbalance the capacitor voltages, and the methods to correct this imbalance are explained together with experimental results obtained with a 4-kW prototype. [ABSTRACT FROM AUTHOR]

Abstract The problem of optimal power management for uncertain off-grid hybrid systems is studied in this paper. A suitable parametrization of the energy sources and sinks is used to obtain a graphical representation of the feasible set along with a direct observation of the solution and its piecewise description. The proposed approach pretends to clarify how the optimal solution migrates from the use of one source to another as the solar radiation changes and how the dynamic response of the sources restrict the feasible set. A power generation system (PGS) is used to study the limitations that the sun power variability and the parametric uncertainty impose on the optimality; being the PGS constituted by photovoltaic (PV) panels, a fuel cell (FC), an electrolyzer (E) and a battery bank. A simple optimal Power Management Strategy (PMS) is proposed as a result of the analysis and its performance is illustrated in a telecom facility for three different locations in Mexico. Results are shown indicating the viability of the strategy for highly variable environments. Highlights • A graphical approach for optimal power management is proposed. • A parametrization is used to allow simplification of the optimization problem. • The case of parameter uncertainty in the power hybrid system is analyzed. • Results demonstrate that optimal operation is possible in presence of uncertainty. [ABSTRACT FROM AUTHOR]