Tapped inductor Buck - Boost converter

This reference section describes the properties and features of the Tapped inductor Buck - Boost converter component in Schematic Editor

A block diagram and input parameters for the Tapped inductor Buck - Boost converter are given in Table 1.

Table 1. Tapped inductor Buck - Boost converter in the Schematic Editor core library.
component	component dialog window	component parameters
Tapped inductor Buck - Boost		Inductor coupling coefficient L1 (Inductor L1; value in Henries) L2 (Inductor L2; value in Henries) R1 (Resistance R1 in series with L1; value in Ohms) R2 (Resistance R2 in series with L2; value in Ohms) Control (Digital inputs, Internal modulator, Model) S1 (digital input selection for switch S1) S1_logic (active high, active low) Gate control enabling (enables usage of external digital signal to enable switching) Sen (digital input selection for gate enable) Sen_logic (active high, active low) Weight = 1

A schematic block diagram of the Tapped inductor Buck - Boost switching block is given in Figure 1 with its corresponding switch arrangement and naming.

Digital inputs, when selected as the Control parameter, enables you to assign gate drive inputs to any of the digital input pins (from 1 to 32). 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 S1_logic parameter is set to either active high (i.e. high-level input voltage VIH which turns on the switch) or active low (i.e. low-level input voltage VIL which turns on the switch). The gate drive logic depends on your external controller design.

The Internal modulator, when selected as the Control parameter, enables you to use the internal PWM modulator for driving the S1 switch instead of the digital input pins. In this configuration, two additional component inputs will be present. The En input is used to enable/disable PWM modulator control, while In is used as the reference signal input for the internal PWM modulator.

Model, when selected as the Control parameter, enables you to set the IGBT gate drive signal directly from the signal processing model. The input pin s_ctrl appears on the component. It is a single element input, where that value controls the S1 switch gate. When controlled from the model, the logic is always set to active high.

When in series, L1 and L2 combine to make an equivalent inductor with an inductance value calculated as: $L_{e q} = L_{1} + L_{2} + 2 ∙ k ∙ \sqrt{L_{1} {∙ L}_{2}}$ , where k amounts to Inductor coupling coefficient parameter. During switching transitions, the total energy of the inductors remains unchanged.

Parameters R1 and R2 are resistance values for parasitic resistors of inductors L1 and L2 respectively. Tuning these resistances can significantly dampen the dynamic transitions during set point changes. Leaving these parameter values at 0 will disable these resistors.

Figure 1. Schematic block diagram of Tapped inductor Buck - Boost 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.