Diode reserve recovery current affects the IGBT turn-on characteristics. Busbar inductance influence the turn-off switching loss, it creates off state voltage spike across the device. In the two-level converter, when bottom IGBT device is turned-on, the conduction transfer from top diode to bottom IGBT and vice versa during IGBT-turn-off. A sinusoidal output load current with sinusoidal voltage modulation signal enables you to simulate for different power factor, power frequency, and switching frequency. A sinusoidal PWM gate modulation signal is used along with a sinusoidal output collector current to simulate the voltage and current stress on the IGBT-diode device combination in a typical two-level converter. A double pulse gate signal is used to determine the single turn-on and turn-off characteristics. The IGBT device under test is placed in the lower (IGBTL) leg of a converter. This model plots the IGBT characteristics for both double pulse and sinusoidal PWM gate signals. This plot shows the extension of the datasheet data to include points at the DC bus voltage for the device in this example. For good simulation speed and accuracy, you must ensure accurate and smooth $ values around the smaller collector-emitter voltages. In converters, an IGBT device operates in switching mode. In these cases, to avoid extrapolation to non-physical current values, provide some estimated values at higher voltage ranges. Note that many datasheets only provide the $ versus $ data for the $ up to 5V, but a switching IGBT device goes through a transition from 0V to the DC bus voltage. You can perform a more approximate parameterization by using the datasheet tabulated values only. You can create the necessary tabulated data for the block from the datasheet characteristic plots. Parameters for thermal model (Foster, Cauer, or simple ). The datasheet information usually includes:ĭiode as a function of for two junction temperatures. The block parameterization matches the data in the manufacturer datasheet. It also supports the definition of nonlinear charge characteristics either through simple physical equations or lookup tables. The N-Channel IGBT block provides a detailed model of an IGBT device by supporting the definition of non-linear I-V characteristics, either through physical equations or by lookup tables. The N-Channel IGBT block is more suited to detailed designs, such as gate driver design and simulating peak switching voltage and current. The IGBT (Ideal, Switching) block is more suited to system-level simulations. The two blocks provide support for different modeling fidelity levels. The N-Channel IGBT and the IGBT (Ideal, Switching) blocks in the Simscape™ Electrical™ library both model an IGBT device. IGBT devices are the most used semiconductor switches for high-power inverters thanks to their unique ability of better switching frequency, simpler gate driver, and available power rating. The busbar inductance is calculated either through lab measurement or by 3-D electromagnetic simulation. The parasitic inductance of the busbar that connects the IGBT device with the DC bus is assumed to be 30nH. The TO-247 package contains an IGBT device with a continuous current rating of 50 Amperes and 650 Volts rating. Because the minimum required DC bus voltage is equal to 2*208*sqrt(2/3) = 340 Volts, this example chooses a standard 400V DC bus.ĭue to the required currents and voltage, the converter needs an IGBT rated at more than 450Vdc and 50A. The RMS current of the converter is equal to 15e3/(sqrt(3)*208) = 41.6 Amperes and the current peak is equal to 59 Amperes. This example is based on a 15 kW converter that operates in a three-phase grid with frequency of 60Hz and line voltage of 208 V. This figure shows the data flow and the respective file names used in this example. To load the device parameters in the workspace, at the MATLAB Command Window, enter: High-Power Converter Design Data Flow Diagram The ee_converter_design_datasheet_igbt_parameterized_data MAT file contains the parameterized data for the N-Channel IGBT, Diode, Heatsink, and IGBT(Ideal, Switching) blocks. If you want to use this example for other IGBT and Diode devices, to carry out the trade-off studies and design optimization, you must provide proper parameterized data that is efficient to simulate. The characteristics curves in the manufacturer datasheet provide the parameters for these blocks. The Diode model parameter of the Diode block is set to Tabulated I-V curve. The Modeling option parameter of the N-Channel IGBT block is set to Full I-V and capacitance characteristics. Window.dataLayer = window.The N-Channel IGBT and Diode blocks of this example are parameterized to correctly captures the on-state losses and the switching losses.
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