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HVDC Electrical Power cOnversion and DIstribution System

Periodic Reporting for period 2 - HEPODIS (HVDC Electrical Power cOnversion and DIstribution System)

Reporting period: 2018-01-01 to 2019-06-30

The HEPODIS project aims to develop a new electrical power conversion and distribution system more efficient and reliable for High Voltage Direct Current (HVDC) for the electrical power supply of essential loads to be implemented and integrated in the Regional FTB2 Demonstrator. The need of a new Electrical Power Distribution in regional aviation comprehends: intelligent electronic systems to manage essential electrical loads, minimal voltage drops, minimal risk of safety issues from leakage currents, minimal risk of nuisance trips from lightning strikes and minimal risk of damage from high inrush currents.

The electrical power system for High Voltage Direct Current (HVDC) will comprised, mainly, two dif-ferent sub-systems: power conversion unit and electrical power distribution center. This technology that will be brought up to TRL6 will continue the work on previous European and International Projects and will contribute to the demonstration activities that have been identified in CleanSky2 requiring more efficient, compact and reliable systems. High Voltage Direct Current (HVDC) developed in HEPODIS will have a lot of benefits and advantages, especially the weight savings either through higher voltage and a through simplified load converters. This means less fuel burn and less gas emissions.

The main objectives of the project are:

-Design, manufacturing and qualification of new regulated Transformer Rectifier Unit (TRU) equipment to supply an HVDC distribution system in order to supply essential loads in the regional aircraft FT2B.
-Improve the characteristics of TRU in relation to the existing equipment: functionality, electrical efficiency, power density, safety, advance control and monitoring and use of advance semiconductor technologies.
-Generate a realistic model of the TRU in order to be integrated with the rest of the models of the HVDC systems. The model must reproduce precisely the working conditions of the real system to avoid integration problems and support the permit to flight phase.
-Specify, design, develop, manufacture, qualify and validate a HVDC Distribution Equipment for essential loads from Flight Control System for IADP Regional Aircraft FT2B.
-Integrate power generation system and the electrical power distribution system.
-Improve effectiveness, reliability and efficiency compared with current architectures.
-Model and simulate electrical performance, compared with real system performance for supporting design, testing and certification strategies.
-Employ new technologies and innovative integration in the equipment. New levels of voltage, architecture, energy management concepts, power electronics devices. More safety due Power Distribution becomes more critical.
-Support integration of the equipment in IADP Regional Aircraft FT2B and flight test.
During this project two different equipment are being developed, HVTRU (developed by SkyLife, it will be an electric power conversion unit from 115VAC, triphasic and variable frequency, to 270 VDC) and PDU (developed by TEMAI, it will be an electric power distribution unit at 270VDC). Both equipment will be incorporated and flight tested in the Airbus DS platform C295 FT2B in order to provide it with an architecture capable to feed the Electro-mechanical actuators (EMAs), that control the flight surfaces (Ailerons and Spoilers), with 270VDC, and in this way, transport more electric power reducing the wire section just as the overall weight of the system.

It should be noted that several technologies required for this project have to be developed from TRL0 to TRL6, minimum necessary to permit to fly. Following, a summary of the activities performed since project starts (July 2016) until the end of the 2nd reporting period (June 2019), is presented.

Since both equipment have to be installed in the aircraft and be flight tested, they have to be developed according to the DO-254 normative for Hardware electronics and DO-178 for embedded Software. During this period all the plans and standards have been developed, for HW (PHAC, HDP, HVVP, HPAP, HCMP, ECMP, HRS and HDS) and SW (PSAC, SDP, SVP, SQAP, SCMP, SECI, SRS, SDS and SCS), and validated by the HW assurance and SW assurance Airbus DS departments.

Preliminary design was developed and validated by Topic Manager during PDR meeting held on November 2017. During this phase Supplier Equipment Specification (SES), Compliance Matrix (SM), Interface Control Document (ICD), Supplier Development Plan (SDP), Preliminary Safety Assessment (SSA), Reliability Report (RR), Qualification Program Plan (QPP), Validation and Verification Plan (VVP) and Equipment Analysis Performances Report (EAPR) have been prepared and uploaded to the JU application.

After the preliminary phase, laboratory prototypes to validate concepts have been manufactured and tested. Also a detailed design has been performed generating and/or updating the following documentation: SES, ICD, SSA, PHAC, PSAC, QPP, QTP, EAPR, 3D Model, PFT, FMEA, FMES and ATP.

Moreover, electronic design, mechanical design and simulation effort have been performed in order to develop and manufacture the Laboratory equipment (LUAR) that will be delivered to Airbus DS to be tested in its integration laboratory. In addition, SkyLife and TEMAI have developed test means in order to be able to check the equipment under developing.
• HEPODIS will develop a new electrical power conversion and distribution system more efficient and reliable to supply essential loads using HVDC voltages. To do this, advanced material topologies and control strategies will be used.
• The main contributions of the technology addressed in HEPODIS to the identified impacts are:
o Improvement of fuel consumption due to a more efficient power density.
o Improvement of fuel consumption due to a more efficient power transfer and usage.
o Improvement of fuel consumption due to a reduction of weight of power converter.
o Improvement of power generation capabilities due to better energy management.
o Decrease of maintenance operations and maintenance costs due to built-in testability.
o Improvement of reliability and safety due to architecture and high reliable switching devices with protections implementation.
o Increase of the power quality of the HVDC system.
• HEPODIS establishes an important progress beyond the state-of-the-art as no previous systems based on HVDC for essential loads have been implemented and tested before in an aircraft. This project will close the gap between technology validation at lab level and prototype demonstration in an operation environment.
• HEPODIS will contribute to the huge effort required to maintain global leadership for aviation in Europe and meeting the needs of its citizens, a sector being a key component of the existing European Gross Product (GDP) and employment. The forthcoming challenges expressed by Airbus and Boeing of over 29,000 aircraft needed in the coming 15 years set a large market opportunity for enhancing the European footprint. HEPODIS, aims to support development within Europe of indigenous solutions in order to support increased revenue, and hence jobs within the EU.
• HEPODIS project contributes to and strengthens the leading role of the EU to combat climate change, since the HVDC Electrical Power Conversion and Distribution System developed, as aforementioned, allows improving power density and efficiency.