Category | Design Considerations

Series and Parallel Connection of Diodes and Thyristors

Posted on 25 March 2020

                    Parallel connection of thyristors In parallel thyristor circuit arrangements, homogenous current distribution is required from the moment of firing and throughout the entire current flow time. For this purpose, steeply rising trigger pulses of sufficient amplitude, as well as symmetrical line impedances in the main [...]

Semiconductor Models

Posted on 11 March 2020

                This article looks at semiconductor models used in electric circuit simulation. Before starting to look for suitable models, the following question must always be answered: What properties does my model have to have to meet the simulation task at hand? Analysis of the circuit operating principle: Ideal [...]

IGBT and Diode Switching Loss Calculation

Posted on 08 March 2020

              In power electronics, both IGBT and diodes are operated as switches, taking on various static and dynamic states in cycles. In any of these states, one power dissipation or energy dissipation component is generated, heating the semiconductor and adding to the total power losses of the switch. Suitable [...]

Mounting of Capsule Diodes and Thyristors (disc cells)

Posted on 22 February 2020

  Disc cell housings possess two thermal contact surfaces. For maximum current capacity yields, double-sided cooling (DSC) is usually used. For this purpose, the cell is clamped between two heat sinks using a clamping fixture as described below. In lower load applications, single-sided cooling (SSC) is used as a standard practice as well. The electrical [...]

Driver Parameters and Switching Properties of IGBTs and MOSFETs

Posted on 18 February 2020

              The important features of driven power MOSFET or IGBT are dependent on VGG+, VGG-, and RG ratings. The table below lists many of these features and provides an initial overview of how they relate to VGG+, VGG-, and RG. The symbols in the table are to be interpreted [...]

Evaluation of Temperature Curves Regarding Power Module Lifetime

Posted on 01 February 2020

              All internal connections of power modules are subject to aging caused by temperature fluctuations. The fatigue of material as well as wear and tear is caused by thermal stress due to the different expansion coefficients of the connected materials. Module lifetime or respectively, the number of possible temperature [...]

Overload and Short Circuit Behavior of IGBTs and MOSFETs

Posted on 28 January 2020

                    Overload Essentially, the switching and on-state behavior of IGBTs and MOSFETs under overload does not differ from "standard operation" under rated conditions. In order not to exceed the maximum junction temperature and to ensure safe operation, the overload range has to be restricted since increased [...]

Innovative Connections for Industrial Controls

Posted on 25 January 2020

      There are strict requirements for industrial controls - connect them to the technology of the future Weidmüller     Advancements are constantly being made in semiconductor technology for industrial automation. They make it possible to manufacture increasingly more complex controls. At the same time, cost pressure and the demands of plant safety [...]

Parasitic Inductances and Capacitances in Converters

Posted on 23 January 2020

              To analyze the individual effects of parasitic inductances and capacitances and their interdependence in converters, it suffices to examine one commutation circuit. Figure 1 shows the commutation circuit of an IGBT converter with parasitic elements, consisting of DC link voltage Vd (corresponds to commutation voltage VK) and two [...]

Gate Current and Gate Voltage Characteristics for Drivers

Posted on 18 January 2020

              The switching behavior of MOSFET and IGBT modules can be largely controlled by the gate capacitance recharge speed (i.e., in this case: gate capacitance = input capacitance CGE + CCG). In theoretical borderline cases, the gate capacitance recharge may be controlled by resistance, voltage, or current (Figure 1). [...]