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Smart programmable load and source

Final Report Summary - SPLS (Smart programmable load and source)

Executive Summary:
This is the final report for project SPLS with number 307727 and closing date of May 30, 2016.

Project Context and Objectives:
State of the art – Background
Future aircraft grids intend to use high voltage DC buses to distribute electric power in the aircraft. These DC buses feed various loads such as electromechanical and electro hydraulic actuators.Currently 270 VDC and 540 VDC are the voltage
levels being considered for standardisation. The first generation of more electric aircrafts will run on 270 VDC. 540 VDC is a candidate for later generations of aircraft grids.The figure below shows the example of a 270 VDC bus. As shown, this high-voltage DC bus provides both -270 VDC and +270 VDC with respect to the aircraft chassis. Use of both a positive and negative voltage allows to maximize power transfer while minimizing the amount of copper needed to do so.
Proper load balancing between the positive and negative line leads to a minimum of current passing through the 0 V return path. As such, copper needed to implement the 0 V return path can be minimized.Aircraft grid voltages and currents Power transfers between the aircraft grid and its connected components go in both directions.Some components will only consume power but other components, like batteries and motor/generators may both consume (store) and deliver power to the grid. Grid stability is determined by the power balance between components delivering power and components consuming power. In studying grid stabilitybehaviour, both the long-term and short-term power balance is of importance. Short-term power imbalances may cause transients that can disturb the behaviour of the devices attached.

Given the above, systems needed for the physical emulation and test of DC aircraft grids must satisfy following requirements
● Solutions must provide or interact with 0 VDC,+270 (540) VDC and -270 (-540) VDC lines.
● For generator emulation, system outputs must be available that act as 270 (540) VDC voltage sources capable to inject power into or absorb power from a load under test..
● For load emulation, system outputs must be available that act as current sources able to inject power in or absorb power from a 270(540) VDC generator under test.
● Both voltage source and current source outputs must be capable to inject or absorb fast-varying power transients.
● For grid and component monitoring, there is a need for distributed current and voltage measurements. Measurements need to be time-synchronized with each other and with the power actuators (generator/loademulations) as to provide a grid-wide picture
of the impact that components have on one another.
● Solutions must be scalable. As the grid grows,it must be easy to add or remove loads and sources as well as measurement points.Aircraft grid test setups mix “real” devices-undertest with electrical load and generator emulations.An example of an aircraft DC grid with physical and emulated components is depicted above. Here, the components marked by “I” represent electrical load emulations (current sources) while the components marked by “V” represent generator emulations (voltage sources).
The grid may also contain “real” devices under test (DUT).
Description of work
SPLS focuses on the design of a versatile power module that can act both as source and generator.The stage covers both DC and 400 Hz AC applications. DC applications include battery emulation, fuel cell emulation and emulation of hydro-electric and electromechanical actuators. AC applications include 400 Hz grid and load emulation. The power stage’s flexibility is twofold
• Flexible hardware architecture: the system’s output section is partially reconfigurable. As such, it can optimally adapt to the characteristcis of the device under test.
• Flexible software architecture: the system builds on an open and flexible software platform. Software is highly configurable.Moreover the entire system can easily be
reprogrammed and is capable of running a multitude of (user-developed) application programs.

Software flexibility is linked to the innovative networking and signal processing architectures experimented with as part of the SPLS project.

Project Results:
Exploitation of GAP foreground (results and other outputs)
Triphase developed a modular and multifunctional smart programmable electrical load and source (SPLS). The SPLS modules are used as part of a wider test bench for more-electric aircraft. The Triphase SPLS module distinguishes itself in combining a configurable hardware architecture with a flexible and reprogrammable software architecture. This allows SPLS users to readily adapt to the test setup at hand, both in terms of converter hardware configuration as well as control software strategy. As such, it rises beyond a mere power converter: it is a platform suited for building advanced power conversion applications for the research and test markets.

For Triphase, the various use scenarios and associated performance of the SPLS, provides valuable input for improvements in future designs. Managing the many different use cases has proven a great challenge. Already and during the course of the project, many of the outcomes have integrated in new product iterations of what is now called the Triphase PMxTM product series. As such, project results are deployed in Triphase power converter products for avionics applications as well as for the research and test market in general.
Engagement of potential end users and other stakeholders
Triphase’s main focus is on the research and test market for power electronics and power systems prototyping. Next generation products, coming out of the experience gained within the project, have already been deployed in a wide variety of public and industrial research organisations. Examples include France’s CEA and Germany’s Fraunhofer Institiutes. Together, these organisations cover a wide range of applications, ranging from renewables and microgrids over avionics to automotive.
Typical customers face the challenge to test novel and complex converter designs for which no readily off-the-shelf solutions exist. Here, the versatility of the Triphase SPLS platform proves a major advantage since it enables users to adapt to the situation at hand as they explore uncharted designs and technologies.

Factors and constraints that could affect the envisaged exploitation
In order to enter some specific markets, additional certifications may be required. This not only requires certification of the products (CE, UL, etc.) but also of the personnel (e.g. security clearances in the U.S.). To cover the latter, Triphase is looking to establish partnerships with companies that have a complementary product offering as well as experience in the relevant industries and/or countries. Triphase aims for partners willing to offer integration and customization services upon the Triphase platform. Although Triphase has the skills to provide integration and customization services, the type of partnerships described above are important in order to scale up our operations and to extend our reach in the market.

Potential Impact:
Main dissemination and communication activities
Dissemination efforts focus on workshops where we explain our concept of the open and flexible SPLS platform for power conversion research and test. These workshops focus both on the technical concepts as well as the possible use cases. Workshops are organised together with key customers in a particular geographical region. Two major workshops to date have been a workshop with Fraunhofer IWES in Kassel, Germany and a workshop with IMDEA in Madrid, Spain.
Triphase also submits papers to conferences in order to promote the ideas behind the SPLS within the research community. Conferences include EPE, ECCE, Compel and IECON.
Communication to the general public is mainly managed via the Triphase website.

List of Websites: