Final Report Summary - EPOCAL (EPOCAL: an Electrical POwer Center for Aeronautical Loads) Executive Summary:The main objective of the current project is the development of an Electrical Power Center (EPC) integrated with a devoted Control Console (CC), enhanced with advanced electrical power management strategies for the aims of the in-flight demo electrical validation and verification activities. The project is based on the following key-points:1) an Electrical Power Center equipped with Solid State Power Controllers (SSPCs) for both power management and protection functions will be implemented. Most recent technologies will be included in the power center, referring to the recent state-of-art, in order to guarantee compliance with selected aeronautical standards. The SSPC component will be ad-hoc designed for the implementation of both the power management strategies and protection functionalities.2) a firmware will be designed and implemented for monitoring and supervision of the EPC, particularly referring to Electrical Energy Management (EEM) concept verification. The software will be able to perform several analyses, referring to preprocessing (i.e. configurations pretesting), real time operations (i.e. monitoring and energy management logics implementation) and postprocessing (i.e. plotting and comparison between measured and simulated quantities). The real-time analysis capabilities will be provided through a strong interaction with the EPC computer system, devoted to the E-EM concept implementation. Particular attention will be devoted to obtain reliability and robustness of the CC, as critical component due to a required intensive interaction with the final user during the in-flight demonstration. The proposed Project follows a typical workflow based on requirements analysis, specs derivation, design phase, physical implementation, testing phase, results analysis versus simulations and final equipment validation.As an above evidenced general Project guideline, a major effort will be actuated for ensuring equipment reliability, due to the in-flight testing activities to be performed at the Project final stage. As a consequence, particular care will be devoted also to pre-testing of the complete equipment before final installation and commissioning on site, where a complete set of qualification tests will be performed by a third-part laboratory under subcontracting funding.Finally, the Electrical Energy Management logics re-programmability, both from software (i.e. embedded software) and hardware (i.e. SSPC ad-hoc development) point of view will be considered as a second major guideline for the overall Project workflow, in order to provide a final product able to accommodate the end-user needs at its best.Project Context and Objectives:The activity is split in five work packages, namely Design (WP 1), Implementation (WP 2), Testing and Validation (WP 3), Optimization & Support (WP 4). Besides, Management (WP 5) activities have been scheduled in order to coordinate the Consortium actions. A first WP1 (Design) phase is conducted in order to analyze the fundamental requirements for the Project objectives, with respect both to hardware and software aspects. In details, referring to the hardware part, the EPC and CC are considered as equipment composed by several elements. For each of them, first a list of requirements to be implemented by the hardware part is derived. Next, a comparative study of the basic hardware elements for both EPC and CC is performed, referring to the commercial off the shelf elements and taking into account crucial parameters such as weight, reliability and compliance with aeronautical standards. At the end of this preliminary phase, a complete set of commercial equipment is selected, constituting the main electrical core of the EPC, excluding the SSPC components that will be ad-hoc designed in this phase. Successively, EPC hardware design task is performed. Different solutions are considered, referring to compactness, robustness and user-friendlessness critical parameters to be optimized. Besides, the selection of a fast and reliable communication protocol between CC and EPC is performed, among the various solutions currently available. During this phase, also software requirements are elicited and collected. The definition of a software architecture for the EPC follows, considering the requirements previously derived as inputs to be processed. Moreover, the simulative models for each electrical component are implemented in MODELICA/SABER simulation language, starting from general purpose blocks and customizing them with respect to the real equipment. As a net result of this WP, a rough estimate of overall EPC weights and dimensions is provided, as well as the related CAD drawings. Moreover, the related models are provided, with a basic set of simulation results to be validated against experimental results, successively obtained in a subsequent phase. In the subsequent WP 2 (Implementation), the hardware development of the complete EPC equipment is performed. First, a number of SSPC modules are physically realized and tested, in order to obtain the latest basic electrical blocks required for EPC development. Subsequently, an integration activity of the electrical elements follows, where some of the EPC and CC constitutive elements (e.g. racks and bars) realization tasks are assigned to specialized companies in order to obtain a high-quality final product.Once developed the EPC as standalone, it is necessary to provide adequate electrical, mechanical and cooling interfaces to the equipment. A set of document is produced in order to punctually specify the device interfaces, in order to minimize the interconnection problems with other equipment exchanging power flows with the EPC. Similarly, also the physical connections and related communication protocol between EPC and CC are implemented. Simultaneously to hardware development, also the EPC software is developed, considering as input the architecture and software requirements defined during previous WP1. In detail, the E-EM logics are first investigated for the test configuration defined in the Call text. A formal approach based on supervisory control theory is here proposed, in order to derive a rigorous strategy for intelligent energy management strategy implementation. Such strategy is successively translated as onboard firmware for the EPC computational mainboard, constituting the core of the real-time interaction between the CC and the EPC. Successive WP 3 (Testing and validation) activities is focused on qualification tests, in order to demonstrate the compliance between the Project results and the aeronautical standards, and safety for flight tests, for guarantying the safe insertion of EPC+CC hardware on the target ATR-72 electrical network. At the beginning of these WP activities, a complete test plan is derived in order to fully specify the forthcoming testing activities, including a set of test cases to be performed and related details. The testing procedure to be successively performed involves two main steps, aiming at reducing fault risks. First the single EPC and CC main elements are singularly tested in order to verify the correctness of the electrical elementary parts. Successively, the qualification tests are performed adopting mainly instrumentation available at Participant laboratory. As a second step, the complete equipment is delivered to a specialized laboratory for aeronautical devices testing, in order to perform safety for flight tests aiming at obtaining a quality certification, following the test plan formulated at the very beginning of WP3 activities. Once verified the communication correctness between the EPC and CC, a final testing phase is performed, focusing mainly on the correctness of the energy management algorithm and the software functionalities. A representative set of test cases is performed, where obtained results are collected in a devoted document, in order to evidence the overall correctness of the operations involving simultaneously hardware and software functionalities of the equipment. A final WP 4 (Optimization and support) is focused on the analysis of the feedbacks collected during the various test phases, in order to improve the equipment performances.Project Results:EPOCAL main scientific result has been the development of a new supervisory control technique for electrical energy management of aeronautical networks, named Electrical-Energy Management (E-EM). This technique, aiming at managing the overload conditions of the generator in order to reduce its size, and providing an alternative to the total shed of the loads by introducing techniques of voltage chopping, has been succesfully tested by using a modular structure composed by a Master module, embedding the logics, and several Slave modules, physical (i.e. DC/DC converters) and virtual (i.e. protocol with E-ECS). The technique itself is innovative, being the first example of supervisory control for aeronautical equipment for energy management purposes. Moreover, a number of Solid State Power Contactor have been used as main core of the DC/DC converters, adopted for voltage chopping. Thie SSPC embed a particular matrix structure, both referring to the switches and the filters. This particular structure has led to a reduction of the converter size, as main technological result of the EPOCAL projectPotential Impact:Supervisory control of the GRA AEA demo in-flight test, one of the main topics of the EPOCAL Project, is an innovative method proposed for a more intelligent load power management, with respect to state-of-art techniques. The objective of the discussed highlevel control is mainly the discarding of generator overload capacity, therefore forcing weight and volume to stay within predefined limits for aeronautical applications. It is expected that the consequential reduction in fuel burn and emissions will enhance the competitiveness of European aircraft products. Furthermore, it is expected its insertion as a standard component for future virtual aircraft model. Therefore, the E-EM strategy may become a basic technology for next generation multiphysics aeronautical network model, possibly implementing updates as a consequence of different networks to be monitored (e.g. helicopters and jets). Besides, the ability of optimize power load consumptions may be of value also for other alternative transport vehicles (marine, rail and road vehicles), suggesting similar supervisory control strategies for reduction of costs and size of electrical generators. This Project will therefore have a significant impact on the competitiveness of European manufacturers. Through the long-term potential to improve fuel efficiency and reduce fuel burn, it should also have a wider impact on society and the environment as a whole. The insertion of SSPCs as EPC contactors is a main point of the EPOCAL proposal. As highlighted also in the state-of-art section, currently classical RCCBs are adopted, moreover discarding any possibilities for energy management function. The inclusion of these new generation contactors in the EPC can lead to many benefits. Primarily, it could be possible to implement new E-EM logics for voltage chopping of loads not already considered at the current stage (e.g. the WIPS, due to their basically resistive nature), by simply connecting the load to the EPC and reprogramming the E-EM logics through the Control Console. Moreover, the addition of intelligence to switching contactors could lead to a more efficient monitoring and control of the attached loads. As an example, more complex strategies with respect to the classical PWM, e.g. sliding or adaptive controls, could be implemented directly at low-level acting on the internal computational devices of the SSPCs. The whole electrical system, in conclusion, will be safer, more reliable, and more energysaving. 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