Learn How Fuji Electric Deploys Hardware-in-the-Loop (HIL) for UPS Control Testing
Story Highlights
- Application: Fuji Electric’s Kobe site uses the Typhoon HIL platform for their Uninterruptible Power Supply (UPS) development.
- Challenge: To overcome the typical limitations of open-loop and offline simulations in the early product testing stage, as well as the limitations of the high-power tests in the late product testing stage.
- Solution: The adoption of controller Hardware-in-the-Loop (C-HIL) made it easy to develop and debug new control software functionality, as well as verify the operation in cases that are difficult to reproduce in a high-power lab.
- Result: Typhoon HIL reduced the time and cost of UPS control development and increased test coverage.
- HIL Tested means quick reliable results with lower costs and higher flexibility.
About Fuji Electric
Since its establishment, Fuji Electric’s Kobe site has served as the development and manufacturing hub for advanced power electronics converter-based products. We had a unique chance to talk to their control development and control testing team and learn first-hand how they use the Typhoon HIL platform for their Uninterruptible Power Supply (UPS) development.
The Fuji Electric team (from left to right): Mr. Kazuyoshi Umezawa, Mr. Motohiro Tsukuta, Mr. Takuya Kimizu
What does Fuji Electric’s UPS development department do?
Our team in Fuji Electric is responsible for the development of a whole spectrum of uninterruptible power supply (UPS) products, namely: small UPS systems (1000kVA) for commercial use, MW scale UPS systems for data centers (1.5MVA), as well as high-power (1MVA) inverters for photovoltaic power generation, and fuel cells power converters (100kVA).
How did you learn about Typhoon HIL?
A few years ago, we made an internal decision to adopt Controller Hardware In the Loop (C-HIL) technology to improve our control development and control testing processes. After initial research, we found five companies that were offering HIL products, looked at their catalogs, and did a deep dive into the specs and performance. In the end, we chose the Typhoon HIL solution; not only were the HIL specifications superior to other solutions, but Typhoon HIL offered a complete solution comprising software, hardware, and engineering services.
We felt that using only off-line simulators and lab tests was seriously slowing down our product development. - Mr. Motohiro Tsukuta
Challenges
Can you tell us about your design and testing processes before HIL?
Before we adopted C-HIL for our control development and testing, we relied heavily on three methods:
- Offline simulation;
- "Open-loop" HIL simulation;
- High-power laboratory testing.
Offline simulation for early testing (early V&V) of the controller is very limited since simulations use low-fidelity model abstractions of real control firmware/hardware; furthermore, simulations are typically very slow and time-consuming. In addition to offline simulation, we debugged controllers by using signal generators as stimuli to the control board under test, what we call an "open-loop" HIL (early V&V). This approach is seriously limited since we couldn’t simulate the converter power stage model "closed-loop" with the controller.
As a final stage of controller testing (late V&V), once the power converter is designed and ready, we would be debugging the software in our high-power laboratory. Injecting faults during the actual high-power tests was expensive, dangerous, and potentially catastrophic. Hence, achieving good test coverage with the real power stage was very difficult and expensive. Also, when testing the parallel operation of multiple UPS systems, power requirements would increase requiring special loads, additional personnel, and hence driving the cost and time requirements.