Device couplings - Ideal Transformer

Device coupling components are ideal transformers with a transfer ratio of one. They are used to partition the complete power electronics circuit into separate circuits that are emulated on different HIL devices. These components are only used in multi-HIL configurations where HIL devices are paralleled. Device coupling components define the communication variables between HIL devices, that are exchanged through High Speed Serial Link (HSSL). This ideal transformer block introduces a variable time delay between measured variables and corresponding controlled sources, which is negligible for most practical systems. The inherent paralleling link delay between two directly connected devices is ~0.5 µs, while total delay depends on several factors, including the amount of data that has to be transmitted through HSSL, the simulation timestep, the number of devices in paralleling chain, i.e., if devices exchanging the variable values are connected directly or through other devices in the chain, etc. The total delay between two directly connected devices can be estimated as:

Where Ts is the timestep period, the value of n is 0.5 µs when Ts is ≤ 0.5 µs or 0 otherwise, and m is a value in range [2,4].

Single-phase device coupling

A single phase device coupling component is an ideal transformer with a transfer ratio of one, used to divide the simulated circuit into two sub-circuits. Consequently, the two sub-circuits are distributed and executed in two separate HIL devices. In addition, this ideal transformer introduces a time delay between measured variables and corresponding controlled sources, which is negligible for most practical systems.

Table 1. Single phase device coupling component in the Schematic Editor core library

component	component dialog window	component parameters
Single phase device coupling		Current source side snubber type Current source side resistance: R1 Current source side capacitance: C1 Voltage source side snubber type Voltage source side resistance: R2 Voltage source side inductance: L1

Three-phase device coupling

A three phase device coupling component is of two ideal transformers as shown in Figure 2 with a transfer ratio of one, used to divide the simulated circuit into two sub-circuits. Consequently, the two sub-circuits are distributed and executed in two separate HIL devices. In addition, these ideal transformers introduce a time delay between measured variables and corresponding controlled sources, which is negligible for most practical systems.

Table 2. Three phase device coupling component in the Schematic Editor core library

component	component dialog window	component parameters
Three phase device coupling		Current source side snubber type Current source side resistance: R1 Current source side capacitance: C1 Voltage source side snubber type Voltage source side resistance: R2 Voltage source side inductance: L1

Four-phase coupling

The four phase device coupling component is made of three ideal transformers as shown in Figure 3 with a transfer ratio of one, used to divide the simulated circuit into two sub-circuits. Consequently, the two sub-circuits are distributed and executed in two separate HIL devices. In addition, these ideal transformers introduce a time delay between measured variables and corresponding controlled sources, which is negligible for most practical systems.

Table 3. Four phase device coupling component in the Schematic Editor core library

component	component dialog window	component parameters
Four phase device coupling		Current source side snubber type Current source side resistance: R1 Current source side capacitance: C1 Voltage source side snubber type Voltage source side resistance: R2 Voltage source side inductance: L1