FMI co-simulation in HyperLynx AMS and PartQuest Explore

The functional mockup interface (FMI) is an industry open standard that allows different simulation tools to communicate for a unified, system-wide co-simulation. Co-simulation is often crucial in the design and analysis of complex, multidisciplinary systems. HyperLynx AMS and PartQuest Explore are multidisciplinary simulation tools from Siemens that have introduced FMI compatibility. HyperLynx AMS provides detailed mixed-signal analysis and is directly integrated with the PCB schematic capture and layout flow. PartQuest Explore is cloud-based and supports early architecture exploration and component selection. This FMI co-simulation methodology is demonstrated in this paper with a variety of FMI-compatible tools. These examples showcase how HyperLynx AMS and PartQuest Explore can interface with other simulation tools to analyze complex electromechanical, thermal, and dynamic systems.

How HyperLynx AMS and PartQuest Explore unlock FMI co-simulation

Engineering systems don't live in a single domain: A smartphone board generates heat. A stepper motor responds to electrical signals. A power converter depends on a software control loop. Simulating any one of these separately from the others tells only part of the story. That's the core challenge FMI co-simulation was built to solve, and it's now integrated into HyperLynx Analog Mixed Signal Analysis (AMS) and PartQuest Explore. This paper highlights the integration of Functional Mockup Interface (FMI) co-simulation capabilities into Siemens' HyperLynx AMS and PartQuest Explore simulation tools

What Is FMI Co-simulation?
The Functional Mockup Interface (FMI) is a free, tool-independent open standard that allows different simulation environments to exchange data and run as one unified system. Rather than forcing engineers to rebuild models in a single tool, or manually stitch together results from separate simulations, FMI enables specialized tools to couple seamlessly, each contributing its strengths to a shared, system-wide analysis.

FMI provides a standardized API and a container format called Functional Mockup Unit or FMU, that packages models for import/export between tools. Importing FMUs enables subsystems modeled in different platforms to interact within a unified simulation, substantially improving workflow efficiency and model accuracy. FMUs come in two flavors:

• Standalone FMUs: fully self-contained; the importing tool runs the co-simulation independently
• Tool-coupling FMUs: act as a communication bridge, requiring both tools to run simultaneously

The FMI standard is widely adopted, with FMI 2.0 being the industry’s prevalent version as of 2025. Over 270 tools across disciplines support FMI, including Siemens’ own HyperLynx AMS, PartQuest Explore, Simcenter products, and leading third-party offerings like Simulink and Mathematica. The tool-independence and “black-box” nature of FMUs means that domain experts can collaborate without deep expertise in each other’s tools or exposing intellectual property.

Bridging Electrical, Thermal and Physical Domains
HyperLynx AMS is a robust analog/mixed-signal simulator, tightly integrated with PCB design tools and supporting a range of model formats (SPICE, VHDL-AMS, Verilog-A/AMS, IBIS, etc.). HyperLynx AMS introduced FMI support in its 2510 release, enabling both FMU export and import. Its workflow allows for assigning simulation models directly within the design schematic, reducing errors and time. With the addition of FMI, HyperLynx AMS can now collaborate with hundreds of other FMI-compatible tools for comprehensive co-simulation.

A compelling demonstration pairs HyperLynx AMS with Simcenter Amesim for electromechanical co-simulation. An electrical subsystem driving a stepper motor is modeled in HyperLynx AMS, while the connected mechanical system, lives in Amesim. By exporting a tool-coupling FMU from HyperLynx AMS and importing it into Amesim, both subsystems simulate together.

PartQuest Explore, Siemens' free, browser-based simulation environment, has also gained FMI compatibility, extending co-simulation to the cloud. The paper showcases an example involves Simcenter Flotherm, a CFD tool for electronics thermal management. A standalone FMU exported from Flotherm is imported into PartQuest Explore, where an electrical model simulates a smartphone's real-world usage. The co-simulation captures how each chip's power dissipation drives temperature changes across the board, with the RF chip cooling during offline gaming while the processor heats up. This kind of thermal-electrical co-simulation would be extraordinarily difficult to achieve without FMI. PartQuest Explore can also export tool-coupling FMUs to locally installed tools like Amesim, replicating the same electromechanical workflow demonstrated in HyperLynx AMS, with identical results.

For teams designing complex electromechanical, thermal, or control systems, this is a meaningful step toward truly integrated, first-time-right engineering.

Explore the full list of FMI-compatible tools at fmi-standard.org/tools.