MOSFET

MOSFET models

For real-time/VHIL simulation, there are two implementations available for the MOSFET: modeled as LC model switch, which is the preferred and also the default option, or as an ideal switch (Ron = 0, Roff = inf), which is available through special toolbox.

LC switch is modeled as a small inductance while conducting and a small capacitances while not-conducting. Weight of MOSFET modeled as an LC switch switch is 0.The parameter resistance and the simulation step are defining the actual inductance and capacitance values according to the following equations:

$L=Ts\bullet R$

$C= \frac{Ts}{R}$

Where L and C are the calculated inductance and capacitance, Ts is the simulation step of electrical part of the model, R is the set resistance value.

If an ideal switch model is used, MOSFET is modeled as a short circuit when conducting and an open circuit when not conducting. In this case, a parallel snubber circuit can be defined. It can be a resistance or a series connection of a resistor and capacitor. Weight of MOSFET modeled as an ideal switch is 1.

For simulation in TyphoonSim, MOSFET is modeled as changeable resistance (R_on/R_off).

Control

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 the S1 switch 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. In TyphoonSim, digital signals are read from the internal virtual IO bus. Hence, if some signal is sent to digital ouput 1, it will appear on digital input 1.

Selecting Internal modulator as the Control parameter, enables use of the internal PWM modulator for driving S1switch instead of digital input pin. 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 Model as the Control parameter, enables setting of the MOSFET gate drive signal directly from the signal processing model. The input pin appears on the gate of the MOSFET component. When controlled from the model, logic is always active high.

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.

Ports

• D (electrical)
  • Drain port of the MOSFET component.

• S (electrical)
  • Source port of the MOSFET component.

• ctrl_in (in)
  • Available if model control is selected
  • Input gate signal for MOSFET

• En (in)
  • Available if Internal modulator control is selected
  • Used to enable/disable internal modulator

• In (in)
  • Available if Internal modulator control is selected
  • Used to specify modulation signal value for internal modulator

• Freq (in)
  • Available if Internal modulator control is selected and Variable carrier frequency is selected as the modulator's operation mode
  • Used to specify modulator's carrier frequency

General (Tab)

• Control source
  • Specifies how switches are controled. It is possible to choose between: Digital inputs, Internal modulator, and Model
  • More details about each type of control can be found in the Control section

• If Digital inputs is selected as Control source, the following properties can be used:
  • S1
    • Digital input that is used to control S1 switch
  • S1_logic
    • Logic that will be applied to control signal for S1
    • Active high or active low
  • Gate control enabling
    • If enabled, gives the possibility to control if changes in the gate control signal are applied or not
    • For real-time/VHIL simulation, this property is available only if the Use ideal switch model option is checked
  • Sen
    • For real-time/VHIL simulation, this property is available only if the Use ideal switch model option is checked
    • Available if Gate control enabling is enabled
    • Digital input that enables/disables switching
  • Sen_logic
    • For real-time/VHIL simulation, this property is available only if the Use ideal switch model option is checked
    • Available if Gate control enabling is enabled
    • Logic that will be applied to the Sen signal

• If Model is selected as Control source, the following properties can be used:
  • Execution rate
    • Defines the period between two updates of gate signals for the component. Gate signals are provided as a signal processing input to component.

• If Internal modulator is selected as Control, the following properties can be used:
  • Operation mode
    • Specifies the source of the internal modulator carrier frequency
    • If Operation mode is Fixed carrier frequency, then frequency can be specified on the component properties
    • If Operation mode is Variable carrier frequency, then the frequency can be specified using a signal processing port
  • Carrier frequency (Hz)
    • Available if the Operation mode is a Fixed carrier frequency
    • Specifies the internal modulator's carrier frequency
  • Carrier phase offset
    • Available if Phase operation mode is Fixed carrier phase offset
    • Specifies the internal modulator's carrier phase offset in degrees.
  • Dead time period
    • Specifies dead time for the internal modulator in seconds
  • Reference signal [min, max]
    • Specifies carrier signal minimal and maximal value
    • Vector containing two values: the minimal carrier signal value, followed by the maximal carrier signal value
  • Load mode
    • Specifies on which event the new value of the modulation signal will be applied in the internal modulator
      • If on min is selected, new value will be applied when carrier reaches minimal value
      • If on max is selected, new value will be applied when carrier reaches maximal value
      • If on either is selected, new value will be applied when carrier reaches minimal or maximal value

• Resistance
  • This property is ignored in TyphoonSim. Resistance value will not affect TyphoonSim simulation at all.
  • Available when MOSFET is modeled as an LC switch (Use ideal switch model option is unchecked).
  • Resistance is used to model the inductance of closed switch and capacitance of the open switch. More information about this property, can be found in the dedicated MOSFET models section.
• Snubber type
  • This property is ignored in TyphoonSim. Chosen snubber type and its value will not affect TyphoonSim simulation at all.
  • Available when MOSFET is modeled as ideal switch (Use ideal switch model option is checked).
  • Defines type of the snubber circuit. More information about this property, can be found in the dedicated MOSFET models section.
• R
  • This property is ignored in TyphoonSim. Chosen snubber type and its value will not affect TyphoonSim simulation at all.
  • Available when diode is modeled as ideal switch (Use ideal switch model option is checked) and chosen Snubber type is not None.
  • Defines shunt resistance value of the snubber circuit. More information about this property, can be found in the dedicated MOSFET models section.
• C
  • This property is ignored in TyphoonSim. Chosen snubber type and its value will not affect TyphoonSim simulation at all.
  • Available when diode is modeled as ideal switch (Use ideal switch model option is checked) and chosen Snubber type is R-C.
  • Defines shunt resistance value of the snubber circuit. More information about this property, can be found in the dedicated MOSFET models section.

Advanced (Tab)

• Use ideal switch model
  • This property is ignored in TyphoonSim. Resistance value will not affect TyphoonSim simulation at all. For simulation in TyphoonSim diode is modeled as changeable resistance (R_on/R_off).
  • Defines the type of MOSFET implementation for real-time/VHIL simulation. More information about this property, can be found in the dedicated MOSFET models section.

Extras (Tab)