IGBT leg

Description of the IGBT leg component in Schematic Editor

A block diagram and input parameters for IGBT leg are given in Table 1.

Table 1. An IGBT leg component in HIL Toolbox
component component dialog window component parameters

IGBT Leg

  • Control (Digital inputs, Internal modulator, Digital input per leg, Model)
  • Digital input pins for:
    • S1 (1..32(64))
    • S2(1..32(64))
  • gate_logic (active high, active low)
Weight = 1

A schematic block diagram of the IGBT leg with corresponding IGBT arrangement and naming is given in Figure 1.

Selecting Digital inputs as the Control parameter enables assigning gate drive inputs to any of the digital input pins (from 1 to 32(64)). For example, if S1 is assigned to 1, the digital input pin 1 will be routed to theS1switch gate drive. In addition, the gate_logic parameter selects either active high(High-level input voltage VIH turns on the switch), or active low(Low-level input voltage VIL turns on the switch) gate drive logic, depending on the design of the external controller.

Figure 1. A schematic block diagram of an IGBT leg with corresponding switch naming

Selecting Internal modulator as the Control parameter, enables use of the internal PWM modulator for driving S_top and S_bot switches instead of digital input pins. In this configuration, two additional component inputs will be present. The En input is used to enable/disable the internal PWM modulator, while In is used as a reference signal input.

Selecting Digital input per leg as the Control parameter enables assigning the leg drive input to any of the digital input pins (from 1 to 32(64)). For example, if S_top is assigned to 1, the digital input pin 1 will be routed through the internal dead time module, to the S_top and S_bot switch gate drives.

Selecting Model as the Control parameter, enables setting of the IGBTs gate drive signals directly from the signal processing model. The input pin gates appears on the component. It is a 2-element vector input, where the first value (index 0) controls the S_top gate and the second value (index 1) controls the S_bot gate. When controlled from the model, logic is always active high.

DTV detection, when enabled DTV detection will be signaled during simulation runtime.

Timing

When Enable delays is enabled, turn on and turn off delay of the IGBTs will be included in the simulation. More information about this feature can be found on the dedicated section switching delay.

PESB Optimization enables optimization for number of switch state space modes.

Losses calculation

When the Losses calculation property is enabled, the component will calculate switching and conduction power losses for all switching elements (IGBTs and Diodes or MOSFETs). In the case of MOSFET switching elements, the Diode characteristic represents an internal MOSFET body diode. Switching power losses are calculated as a function of current, voltage, and temperature using 3D Look-up tables (LUTs). Also, 2D input for losses is supported. When a 2D losses table is inserted, it assumes only current and temperature dependance. From version 2020.3, conduction power losses can be defined as a function of current and temperature using Vt and Vd Look-up tables (the previous definition using Vce, Rce, Vd, and Rd properties are removed). These LUTs can be either 1D or 2D. If the LUT is a 1D table, the forward voltage drop depends only on current. If the LUT is a 2D table, the forward voltage drop dependence on the junction temperature is included.

In the MOSFET case under reverse current conduction, the current sharing calculation between the MOSFET channel and the internal body diode is performed. Import options and an explanation of how to correctly fill in all the necessary power loss parameters is described in the import power losses section.

Input/output power losses ports receive/generate vectors of four elements in the case of an IGBT switch type. The first element (index 0) is the upper IGBT, the second element (index 1) is the upper IGBT's diode. The last two elements are the bottom IGBT and its diode, respectively. In the case of a MOSFET switch type, power losses ports receive/generate vectors of 2 elements. The first element (index 0) is the upper MOSFET and the second element (index 1) is the bottom MOSFET.

Availabe mask properties are:
  • Switch type - property to select semiconductor type. Available options are IGBT and MOSFET.
  • Current values - Switching elements current axis [A]
  • Voltage values - Switching elements switching losses, voltage axis [V]
  • Temp values - Switching elements temperature axis [°C]
  • Forward voltage drop definition method - property to select how FVD will be defined. Available options are Voltage and Resistance and LUT - discontinued from the 2020.3 release
  • Vce - IGBT collector emitter saturation voltage [V] - discontinued from the 2020.3 release
  • Rce - IGBT on state slope resistance [Ohm] - discontinued from the 2020.3 release
  • Vd - IGBT Diode voltage drop [V] - discontinued from the 2020.3 release
  • Rd - IGBT Diode slope resistance [Ohm] - discontinued from the 2020.3 release
  • Vt table - Switch forward voltage drop, f(I,T) [V]
  • Vd table - Diode forward voltage drop, f(I,T) [V]
  • Et on table - Switch switching ON losses, output energy, f(I, V, T) [J]
  • Et off table - Switch switching OFF losses, output energy, f(I, V, T) [J]
  • Ed off table - Diode switching OFF losses, output energy, f(I, V, T) [J]
The properties Vce, Rce, Vd and Rd are available only if the Forward voltage drop definition method is Voltage and resistance. The properties Vt table and Vd table are available only if the Forward voltage drop definition method is set to LUT.
Note: Voltage and Resistance definition for conduction losses will be removed with the 2020.3 release. It is recommended to make the transition to the LUT based definition. If a manual transition is not done during the 2020.2 release, automatic initialization of the Vt table and Vd table properties will be performed based on the discontinued Voltage and Resistance properties (Vce, Rce, Vd and Rd).
Note: Elements ordering for Power losses IGBT Leg terminals in the 2018.4 release was [S_bot_igbt, S_bot_diode, S_top_igbt, S_top_diode] and from the 2019.1 release is changed to [S_top_igbt, S_top_diode, S_bot_igbt, S_bot_diode]. These changes also influence the signal ordering for this component.

Forward voltage drop

When the Forward voltage drop property is enabled, forward voltage drop of a semiconductor device will be inserted in the model. It is represented by a variable voltage source in series with an ideal switch. Forward voltage drop parameters for the Switch and its diode are specified independently. Forward voltage drop can be defined in two ways:
  1. based on Vce, Rce, Vd and Rd - discontinued from the 2020.3 release
  2. based on Look-up tables as a function of current and temperature. These LUTs can be 1D or 2D tables. If the LUT is 1D table, forward voltage drop depends only on current. If the LUT is 2D table, forward voltage drop depends also on temperature. Import options and an explanation how to correctly fill all necessary power losses parameters are described in import power losses.
If FVD calculation is based on Vce, Rce, Vd and Rd additional ports on the component are not necessary. If FVD calculation is based on LUTs, an additional port will be present (T_junctions). It is necessary to connect junction temperatures to this port. If Temperature calculation is also enabled, T_junctions port will be replaced with the T_cases port.

For IGBT switches, the input values for FVD are vectors of four elements. The first element (index 0) is the upper IGBT, the second element (index 1) is the upper IGBT's diode. The final two elements are the bottom IGBT and its diode, respectively. For MOSFET switches, the input/output ports are vectors of 2 elements. The first element (index 0) is the upper MOSFET and the second element (index 1) is the bottom MOSFET.

Availabe mask properties are:
  • Switch type - property to select semiconductor type. Available options are IGBT and MOSFET.
  • Current values - Switch current axis [A]
  • Temp values - Switch temperature axis [°C]
  • Forward voltage drop definition method - property to select how FVD will be defined. Available options are Voltage and Resistance and LUT - discontinued from the 2020.3 release
  • Vce - IGBT collector emitter saturation voltage [V] - discontinued from the 2020.3 release
  • Rce - IGBT on state slope resistance [Ohm] - discontinued from the 2020.3 release
  • Vd - IGBT Diode voltage drop [V] - discontinued from the 2020.3 release
  • Rd - IGBT Diode slope resistance [Ohm] - discontinued from the 2020.3 release
  • Vt table - Switch forward voltage drop, f(I,T) [V]
  • Vd table - Diode forward voltage drop, f(I,T) [V]
Properties Vce, Rce, Vd and Rd are available only if the Forward voltage drop definition method is Voltage and resistance. The properties Vt table and Vd table are available only if the Forward voltage drop definition method is set to LUT.
Note: Voltage and Resistance definition for forward voltage drop will be removed with the 2020.3 release. It is recommended to make the transition to the LUT based definition.

Temperatures calculation

When Temperatures calculation property is enabled, component will calculate combined power losses (P_loss) and junction temperatures (T_junctions) for all switching elements (IGBTs and diodes). Combined power losses represent sum of the calculated switching and conduction losses transfered through internally generated Thermal network component. Internally generated Thermal network component also calculates junction temperatures from power losses, input cases temperatures and provided thermal model parameters. Input/output ports for temperatures calculation are vectors of four elements and they are indexed in the same way as explaind in the Losses calculation section. Additional temperatures calculation mask properties are:
  • Thermal networks type - Defines type of internal thermal network
  • Rth switch - List of thermal resistance for the IGBT switch
  • Tth switch / Cth switch - List of thermal time constants or thermal capacitances for the IGBT switch
  • Rth diode - List of thermal resistance for diode
  • Tth diode / Cth diode - List of thermal time constants or thermal capacitances for diode
  • Caculations execution rate - Execution rate in [s] for the losses and temperatures calculation logic

Output Voltage Comparator

Output Voltage Comparator signal is available in the digital signal list of models that contain IGBT Leg components. One such signal is generated for each IGBT Leg used in the model, under the name "component_name_vout_cmp", where component_name is IGBT Leg component's name in the Schematic Editor.

Figure 2. IGBT Leg Output Voltage Comparator Digital Signal

Digital Alias

If a converter is controlled by digital inputs, an alias for every digital input used by the converter will be created. Digital input aliases will be available under the Digital inputs list alongside existing Digital input signals. The alias will be shown as Converter_name.Switch_name, where Converter_name is name of the converter component and Switch_name is name of the controllable switch in the converter.

Oversampling setting (Advanced tab)

With this property, you can select which GDS oversampling algorithm will be used in the IGBT Leg component. There are two options: Global GDS oversampling and Switch-level GDS oversampling. More informations about these algorithms can be found in the dedicated documentation pages. Switch-level GDS oversampling is suitable for applications which use high switching frequency and where more than one GDS transition can happen during one simulation step. Typical examples are Dual-Active-Bridge and Resonant converter applications.

Note: If Switch-level GDS oversampling is enabled in a component that supports it, Global GDS oversampling will be ignored for all components in the same sub-circuit.
Note: Forward voltage drop is not supported if Switch-level GDS oversampling is enabled.