Four level flying capacitor leg

This section describes the four level flying capacitor leg

A block diagram and input parameters for the flying capacitor are given in Table 1.

Table 1. Four level flying capacitor leg in the Schematic Editor core library
component component dialog window component properties

Four Level Flying Capacitor Leg

  • General
    • Control(Digital inputs, Model)
    • S_1 (digital input selection for switch S1)
    • S_2 (digital input selection for switch S2)
    • S_3 (digital input selection for switch S3)
    • S_4 (digital input selection for switch S4)
    • S_5 (digital input selection for switch S5)
    • S_6 (digital input selection for switch S6)
    • Gate control enabling (enables usage of external digital signal to enable the switching)
    • Sen (digital input selection for PWM enable)

Digital inputs, when selected for Control parameter, enables the user to assign gate drive inputs to any of the digital input pins. For example, if S_1 is set to 1, the digital input pin 1 will be routed to the S1 switch gate. In addition, the S_1_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 logic, depending on the user’s external controller design.

Model, when selected for Control parameter, enables the user to set the IGBTs gate drive signals directly from signal processing model. The input pin gates appears on the component and requires a vector input of six gate drive signals in the following order: [S_1, S_2, S_3, S_4, S_5, S_6]. When controlled from the model, logic is always active high.

Gate control enabling, when checked, enables using an external PWM enabling digital signal.

Figure 1. A schematic block diagram of a Four Level Flying Capacitor Leg block diagram with corresponding switch naming

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.