What is a more electric ship?
Shipboard electrical systems are becoming more sophisticated. Conventional mechanical, hydraulic, and pneumatic power transfer systems are replaced by electrical systems. More importantly, a combination of medium speed internal combustion engines with electrical generators, sophisticated electric power distribution system and variable frequency electric drives brings numerous advantages. At the same time it comes with the power management system comprising computer-controlled (synchronous) generators, computer-controlled electrical switches, computer-controlled electric drives and a communication network.
Such a sophisticated power management system needs to be tested under all operating conditions and the most effective way to make such tests is by means of controller hardware in the loop approach.
Why is interoperability an issue?
Field experience shows that state-of-the-art components (internal combustion engines, generators, transformers, protection, variable frequency drives, computer networks, etc.) do not by themselves guarantee a satisfactory system operation. The issue is the software interoperability of the components, i.e. getting them to work as expected within the ever tighter time and budget constraints.
Configuring control and protection software of ever more complex shipboard power management systems can quickly develop into a long and unproductive commissioning effort, result in equipment damage and, in the worst case, lead to serious accidents.
What makes marine business very challenging is a unique combination of high power, low volume, multitude of suppliers, modest standardization, and one-off designs. Due to such boundary conditions the cost of thorough system testing is a significant barrier on the path of wider adoption of marine electrification.
HIL to the rescue!
Shipboard electrical power system are the original microgrids that are now adopting advanced power management solutions. The experience from aerospace and automotive industries has taught us that there is only one way to effectively deal with interoperability issues: the hardware in the loop (HIL) testing way.
What is HIL testing?
Hardware in the loop testing is a method of testing shipboard power management system using a virtual model of the power stage. This means the actual power management software and hardware is interfaced to the HIL model of the power hardware. HIL provides a direct insight in the behavior of the software which controls shipboard power systems. It allows testing of an unlimited number of short circuits and other transients (e.g. fault transients), as well as regular transients in the shipboard power system. Something that is impractical to do on the actual ships.
Virtual, highly realistic, real-time models of the hardware (microgrid testbed) enable testing high power systems without the dangers and costs involved with testing high power.
What is a more electric ship’s digital twin?
Digital twin is a real time model of the ship’s power system hardware running on the Microgrid Testbed.
What is the purpose of the Microgrid Testbed?
The main purpose of the Microgrid Testbed is to comprehensively test the power management (both component level and system level) hardware, firmware, software and communications under all operating conditions including faults in both the islanded and grid-connected mode. Moreover, Microgrid Testbed runs its tests and generates its test reports automatically.
How does the Microgrid Testbed work?
A shipboard power system model comprising smart inverter hardware, PV panels, batteries, transformers, generators, switches, cables, active and passive loads, etc. runs inside a Microgrid Testbed with a 1 μs time step. The shipboard power management system controls its operation in all operating modes. The performance is evaluated against a defined set of criteria ranging from fuel consumption to fault tolerance. From black start to the grid connected mode of operation in the harbour.