BCI-ROM FMU Simcenter Flotherm...2020/11/23 · BCI-ROM Overview Simcenter Flotherm BCI-ROMs: Support multiple heat sources Accurate with any HTC Accurate for all transient time scales

BCI-ROM FMU

Simcenter Flotherm

Byron Blackmore,

Electronics Cooling Product Manager

Where today meets tomorrow

Simulation of Power Electronics

Example

Unrestricted © Siemens 2020

2020-MM-DDPage 3 Siemens Digital Industries Software

Power Electronics – Use Cases

◼ Automotive electronics are subject to a wide

range of operating and thermal conditions.

◼ Transient power dissipation depends on

vehicle speed/acceleration, motor speed/characteristics, driver preferences and

system design.

◼ Challenge: Generate electronics device

temperatures accurately and rapidly enough

to robustly explore reliability and

performance.



Power Electronics Temperature Prediction

◼ 1D Simulation tools are fast enough to support very complex

transient use cases, and are already used to model many aspects of

electric vehicle systems, including the calculation of module power

dissipation.



Power Electronics Temperature Prediction

◼ However, 1D tools cannot adequately

model the thermal aspects of power

electronics modules. They are typically 3D

in nature, and often thermally coupled with other heat sources in the system.

Simcenter Flotherm model of an IGBT module

◼ This has often necessitated the use of full 3D CFD simulation tools to

calculate device temperatures and temperature variations.

◼ For complex transient power profiles, this results in very long

computation times and slow design cycles.



Power Electronics Temperature: The Way Forward

◼ The recent introduction of Boundary Condition Independent

Reduced Order Models (BCI-ROMs) to industry offers an opportunity

to bring together the accuracy of 3D thermal models and the speed

of 1D simulation.

◼ Here we introduce a work flow to provide Flotherm BCI-ROMs in the

industry standard FMU format for use in 1D simulation tools. 1D

tools can then calculate temperatures for power electronics in real

world conditions, allowing full design space exploration without compromising on accuracy or simulation speed.

FMI and BCI-ROMs



BCI-ROM Overview

◼ Simcenter Flotherm BCI-ROMs:

◼ Support multiple heat sources

◼ Accurate with any HTC

◼ Accurate for all transient time scales

◼ Solved up to 100,000x faster than CFD

◼ Inputs: Powers, HTCs, and Ambient

Temperatures

◼ Outputs: Temperatures and Peripheral Heat Flows.



Functional Mock-up Interface (FMI)

◼ The FMI standard https://fmi-standard.org is an open format for sharing simulation models.

◼ The standard specifies two types of FMU (Functional Mock-up Unit):

◼ Model Exchange and Co-Simulation

◼ The FMU Export from Simcenter Flotherm is the Co-Simulation type.

https://fmi-standard.org/



What tools can import Co-Simulation FMU?

◼ 60+ tools, including:

◼ Simcenter AMESim

◼ Simcenter Flomaster

◼ Ansys Simplorer

◼ Matlab Simulink

◼ GT-Suite

◼ And more

◼ See https://fmi-standard.org/tools for the full list

https://fmi-standard.org/tools



Generating BCI-ROM FMUs

◼ Workflow: Create BCI-ROM, then convert to FMU



BCI-ROM FMU Example: Simcenter Flomaster

Liquid Cold Plate and IGBT Module

FMU: BCI-ROM

Device Powers

Heat Transfer Coefficients and Fluid Temperatures

Heat Flows

1D Cold Plate Channel Network

Flow Rate



BCI-ROM FMU Example: Simcenter Amesim

Electronics Topology and EV Performance

FMU| BCI-ROM

(High Accuracy, 100,000x

Faster transient sim)

Junction

Temperature

Cold Plate

Temperature

Coolant Inlet

Temperature

Reliability

EV Range Calculation

Battery Discharge Calculation



Summary

◼ Enabling 1D tools to incorporate accurate 3D thermal BCI-ROMs greatly accelerates the design process and improves product reliability. Simulation

data is generated quickly enough to allow design space exploration of complex systems while fully considering temperature, reliability and system design.

Documents

BCI-ROM FMU Simcenter Flotherm...2020/11/23 · BCI-ROM Overview Simcenter Flotherm BCI-ROMs: Support multiple heat sources Accurate with any HTC Accurate for all transient time scales