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Featured Application: The proposed circuit model is able to foresee the overall current distortion of different lamp configurations. This feature is very useful in the optimal design of lighting systems when a key target is the mitigation of the current distortion due to the power converter inside the energy-saving lamps. Energy-saving lamps are equipped with converters enabling high energy efficiency at the cost of injecting very distorted currents on the mains. The problem is more complex in the emerging smart-lighting scenario where these lamps are also used to perform additional tasks. Harmonics mitigation at the lamp level is expensive; consequently, an optimal lighting system design aiming at reducing both costs and current distortion of the whole lighting system is necessary. A tool able to emulate the current drawn from the lamps is necessary for optimal design. Such a tool has also to consider the fluctuations of the voltage on the mains that usually occur throughout the day. In this perspective, a parametric PSpice circuit is proposed and the netlist is reported in this work. Moreover, the simple procedure to be adopted for computing the parameters is also described. The validation has confirmed the ability of the proposed circuit in emulating the current drawn from various CFLs and LED lamps under different supplying voltage. [ABSTRACT FROM AUTHOR]

Integrated power electronics modules (IPEMs) represent an innovative typology of power electronics assemblies able to guarantee several advantages such as increasing of power density, better management of the thermal flows, and a significant reduction of the package sizes. Their characteristics make them suitable for applications like motor drives or power conditioning. IPEM usage in emerging fields like hybrid automotive traction and electric generation from renewable energy sources is continuously increasing. In this paper, we describe the implementation of a devised flow to generate the layer-based electrothermal PSpice model of an IPEM and the simulation flow of the model. The proposed modeling methodology allows reducing an electrothermal multidomain problem to an electrical single one. The general PSpice-like nature of the proposed model makes it suitable for a wide range of simulation frameworks where the integration of heterogeneous multiphysics models could be a difficult task. The outlining of both electrical and thermal PSpice layers is discussed, and the implementation into the final model, by the assistance of custom electronic-design-automation flow, is presented. Moreover, we describe the validation procedure of the proposed approach, and the results are compared with the ones obtained by a commercial finite-element-based package used as a benchmark. Two simulation approaches related to specific conversion systems, and related issues, are presented and discussed. [ABSTRACT FROM PUBLISHER]

In this paper, a physical model for a SiC Junction Field Effect Transistor (JFET) is presented. The novel feature of the model is that the mobility dependence on both temperature and electric field is taken into account. This is particularly important for high-current power devices where the maximum conduction current is limited by drift velocity saturation in the channel. The model equations are described in detail, emphasizing the differences introduced by the field-dependent mobility model. The model is then implemented in Pspice. Both static and dynamic simulation results are given. The results are validated with experimental results under static conditions and under resistive and inductive switching conditions. [ABSTRACT FROM AUTHOR]

In this paper, a case study application of a new device, which is based on a bipolar-MOSFET cascode connection, is presented. The monolithic device can be designed for high-voltage applications up to 1.7-2.2 kV. The basic features of this power device are described in terms of the physical structure and the electrical performance. An application in the field of dc-dc converters is presented, and the drive unit requirements are investigated and discussed through several circuit topologies that are devoted to energizing the four-terminal device. The advantages and the drawbacks of the device are compared with those of a MOSFET in terms of the switching losses and the command circuitry. The correlation between the physical structure of the cascode and its electrical characteristics is explained to better understand some interesting features of the device. Last, the new device is tested by using a forward converter as a workbench to provide converter designers with useful guidelines concerning the switching behavior and the power losses. [ABSTRACT FROM AUTHOR]

This paper presents a new approach in realizing various carrier-based pulsewidth-modulation techniques by a generalized control algorithm, which is referred to as the universal control algorithm and is obtained via unequal sharing of null states. The flexibility of such an approach allows one to easily and quickly control two-level inverters. Furthermore, this approach may be also extended with few changes to the control of multi- level inverters. The algorithm that is presented here for two-level voltage-source inverters (VSIs) also obtains efficient detection and management of both the linear and overmodulation ranges. In the overmodulation range, which is treated by using the α-β components of the reference-voltage space vector, the algorithm shows the advantage of lower calculation time, thus allowing one, if required, to increase the switching frequency. Several simulation runs have been performed, aiming to test the proposed procedure for both two-level and multilevel VSIs. Finally, the new algorithm was experimentally validated in the case of two-level inverters by using it in a VSI workbench that can carry out several experimental tests. [ABSTRACT FROM AUTHOR]

In this paper, standard-cell Schottky rectifiers along with silicon-based merged p-i-n-Schottky (MPS) and p-i-n diodes, which are realized using a super junction technology, have been analyzed and compared by conducting extensive device and mixed-mode simulations through a 2-D finite-element grid. The main issues that concern these devices, such as the forward voltage drop, the leakage characteristic, and the reverse recovery, are treated, and the superior performances exhibited by the MPS rectifier with respect to the p-i-n diodes are experimentally validated. First, the basics on the used technology are reported by focusing on the high voltage capability of the new devices along with the low forward voltage drop during the ON-state conduction. The reverse-recovery behavior belonging to the MPS diode has been analyzed by exploring through several simulations the internal plasma dynamics. 2-D simulations of the turn-on behavior relative to the Schottky, p-i-n, and MPS rectifiers have been carried out in order to analyze the effects of the voltage overshoot phenomenon eventually occurring in the three diode structures. [ABSTRACT FROM AUTHOR]

In this paper, a new loss minimization control algorithm for inverter-fed permanent-magnet synchronous motors (PMSMs), which allows for the reduction of the power losses of the electric drive without penalty on its dynamic performance, is analyzed, experimentally realized, and validated. In particular, after a brief recounting of two loss minimization control strategies, namely, the "search control" and the "loss-model control," both a new modified dynamic model of the PMSM (which takes into account the iron losses) and an innovative "loss-model" control strategy are presented. Experimental tests on a specific PMSM drive employing the proposed loss minimization algorithm have been perfomed, aiming to validate the actual implementation. The main results of these tests confirm that the dynamic performance of the drive is maintained, and in small motors enhancement up to 3.5% of the efficiency can be reached in comparison with the PMSM drive equipped with a more traditional control strategy. [ABSTRACT FROM AUTHOR]

Focuses on the use of insulated gate bipolar transistors in the field of power electronics. Efficiency of power switches in medium range power converters; Achievement of safe commutations of the switches by simple and effective control circuits; Arrangement of the gate drive units.

Highlights the increased use of MOSFET's and insulated gate bipolar transistor devices in electronic circuits. Reasons for the increased use; What technique is used in the study; Why these techniques were adopted; Details on constraints to consider; Methodology used.

Nowadays, LED lamps have become a widespread solution in different lighting systems due to their high brightness, efficiency, long lifespan, high reliability and environmental friendliness. The choice of a proper LED driver circuit plays an important role, especially in terms of power quality. In fact, the driver controls its own input current in addition to the LED output current, thus it must guarantee a high power factor. Among the various LED drivers available on the market, the quasi-resonant (QR) flyback topology shows interesting benefits. This paper aims at investigating and analyzing the different issues related to the input current distortion in a QR flyback LED driver. Several effects, such as the distortion caused by the ringing current, crossover distortion due to transformer leakage inductance and crossover distortion due to the input storage capacitor have been experimentally reported. These effects, not previously studied for a high power factor (Hi-PF) QR flyback, have been analyzed in depth. Finally, some practical design guidelines for a Hi-PF QR flyback driver for LED applications are provided. [ABSTRACT FROM AUTHOR]