Diode leg

Description of the Diode Leg component in Schematic Editor

A block diagram and input parameters for the diode leg component are given in Table 1.

Table 1. Diode leg component in the Schematic Editor core library
component component dialog window component parameters
diode leg
  • PESB _Optimization
Weight = 1

The schematic block diagram of the diode leg block is given in Figure 1, with corresponding switch arrangement and naming.

Figure 1. The schematic block diagram of a diode leg with corresponding switch naming

Losses calculation

When the Losses calculation property is enabled, the component will calculate switching and conduction power losses for all switching elements (Diodes). 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. Conduction power losses can be defined as a function of current and temperature using Vd Look-up table.

Import options and an explanation of how to correctly fill in all the necessary power loss parameters are described in the Importing power losses data section.

Input/output power losses ports receive/generate vectors of two elements. The first element (index 0) is the upper diode, the second element (index 1) is the bottom diode.

Note: An interactive overview of how you can incorporate power loss calculation in your model is available as part of the HIL for Power Electronics course on HIL Academy, as well as in the video Knowledgebase.
Available mask properties are:
  • Current values - Switching elements current axis [A]
  • Voltage values - Switching elements voltage axis [V]
  • Temp values - Switching elements temperature axis [°C]
  • Vd table - Diode forward voltage drop, f(I,T) [V]
  • Ed off table - Diode switching OFF losses, output energy, f(I, V, T) [J]

Temperatures calculation

When the Temperatures calculation property is enabled, the component calculates the combined power losses (P_loss) and junction temperatures (T_junctions) for all switching elements (Diodes). Combined power losses represent the sum of the calculated switching and conduction losses transferred through an internally generated Thermal network component. The internally generated Thermal network component also calculates the junction temperatures from power losses, input case temperatures, and provided thermal model parameters. Input/output ports for temperature calculation are vectors of two elements and they are indexed in the same way as explained in the Losses calculation section.

Note: An interactive overview of how you can incorporate temperature calculation in your model is available as part of the HIL for Power Electronics course on HIL Academy, as well as in the video Knowledgebase.
Additional temperature calculation mask properties include:
  • Thermal networks type - Defines type of internal thermal network
  • Diode Rth - List of thermal resistances for diode
  • Diode Tth / Cth - List of thermal time constants or thermal capacitances for diode
  • Calculation execution rate - Execution rate in [s] for the losses and temperature calculation logic

PESB Optimization

The PESB Optimization option is available in certain converter models. When PESB Optimization is enabled, all converter's short circuit state space modes will be merged and treated as the same state space mode. For example, if one converter leg within the three phase converter is short circuited and PESB Optimization is enabled, all of the legs within the three phase converter will also be short circuited. This simplification for short circuit modeling can save a significant amount of matrix memory.