Periodic Reporting for period 2 - IMAGINE (Innovative Method for Affordable Generation IN ocean Energy)
Berichtszeitraum: 2019-09-01 bis 2021-11-30
The IMAGINE “Innovative Method for Affordable Generation IN ocean Energy” project aims at developing the Electro-Mechanical Generator (EMG), an innovative Power-Take Off (PTO) concept for wave energy applications able to convert slow speed, reciprocating linear motion into electricity. EMG is based on the integration of a recirculating ballscrew and a permanent magnet generator, an architecture that dramatically improves average efficiency (70-85% also when working outside design conditions), reliability (20 years MTBF) and affordability (CAPEX reduction by over 50%) compared to state-of-the-art PTOs. During the IMAGINE project, EMG technology will be demonstrated through the fabrication of a 250 kW prototype and its testing on a HardWare-Inthe-Loop (HWIL) bench. This will allow progressing its TRL from 3 to 5. A range of Wave Energy Converters (WECs) will be emulated on the HWIL bench and EMG performance, under the action of a robust control system, will be measured and extensively assessed. Furthermore, a FMECA analysis and a subsequent accelerated life test will prove system reliability. HWIL tests will allow reducing technological risk in power rating increase, providing an intermediate step between tank tests and sea trials that represents a critical transition for wave energy development. Finally, an EMG techno-economical assessment and a complete Business Plan for commercialization will be developed. Such activities will be carried out by an international consortium with multidisciplinary skills in marine energy, led by a leading-manufacturing company as UMBRAGROUP S.p.A.
IMAGINE project is related to the topic “Developing the next generation technologies of renewable electricity and heating/cooling”, under the category “Ocean Energy: Development of advanced ocean energy subsystems: innovative power take-off systems and control strategies.
IMAGINE project is related to the topic “Developing the next generation technologies of renewable electricity and heating/cooling”, under the category “Ocean Energy: Development of advanced ocean energy subsystems: innovative power take-off systems and control strategies.
The main objective of the IMAGINE project (“Innovative Method for Affordable Generation IN ocean Energy”) is to develop a new Electro-Mechanical Generator (EMG) for wave energy applications: a ground-breaking technology that can decrease by over 50% the CAPEX of current PTO technologies, while increasing average efficiency above 70% and lifetime to 20 years.
During the reporting period (up to month 18) it was expected to deliver results of Work Packages 2, 3, 4, and 5.
WP2 – EMG integrability analysis and specifications
K2M (previously CA) performed an estimation of the loading environment across relevant design load cases (DLCs) for combinations of target installation sites and WEC types. The combinations allowed the creation of a detailed PTO load envelope that in turn contributed to the design of the EMG (WP3), test bench (WP4) and control system (WP5). WP2 simulation models will provide the calculated PTO input‖ for the HWIL simulation of WP6.
WP3 – EMG prototype design and fabrication
The completion of WP2 provided a set of specifications for EMG prototype design and fabrication. Specifications mainly concern axial screw force, speed, stroke and required damping values for optimal power capture. Based on this the EMG design took place and the main prototype components have been designed to ensure they withstand the design loads and they can be manufactured/assembled with existing processes/tools. In addition, BV M&O performed a FMECA to obtain a preliminary assessment of EMG reliability.
WP4 – HWIL test bench design and fabrication
This WP is dedicated to the definition of the test plan for the EMG and HWIL test bench design and fabrication. WP4 start was triggered by WP2 outputs (EMG specifications) and by partial results of WP3 (EMG prototype). The HWIL testing scheme has been developed integrating on the test bench the control systems defined in WP5 and numerical models developed in WP2. The bench has been developed by VGA and will be operated by UMBRA. In parallel, BV M&O will review all the documents and procedures to help in aligning them to the requirements of a future certification process.
WP5 – Control systems design and implementation
WP5, led by NTNU, used the EMG prototype system design parameters (defined in WP2) and physical constraints such as maximum torque, speed and stroke (derived from WP2 and WP3) as input in order to identify PTO control strategies that can optimize EMG overall power performance. Some control alternatives have been evaluated taking into consideration EMG efficiency at partial load. A number of representative test cases have been analysed, representing both steady state and typical operational transients to identify the most promising control strategy. All the simulation models will be implemented to ease the subsequent implementation in HWIL testing platform in WP6.
During the reporting period (up to month 18) it was expected to deliver results of Work Packages 2, 3, 4, and 5.
WP2 – EMG integrability analysis and specifications
K2M (previously CA) performed an estimation of the loading environment across relevant design load cases (DLCs) for combinations of target installation sites and WEC types. The combinations allowed the creation of a detailed PTO load envelope that in turn contributed to the design of the EMG (WP3), test bench (WP4) and control system (WP5). WP2 simulation models will provide the calculated PTO input‖ for the HWIL simulation of WP6.
WP3 – EMG prototype design and fabrication
The completion of WP2 provided a set of specifications for EMG prototype design and fabrication. Specifications mainly concern axial screw force, speed, stroke and required damping values for optimal power capture. Based on this the EMG design took place and the main prototype components have been designed to ensure they withstand the design loads and they can be manufactured/assembled with existing processes/tools. In addition, BV M&O performed a FMECA to obtain a preliminary assessment of EMG reliability.
WP4 – HWIL test bench design and fabrication
This WP is dedicated to the definition of the test plan for the EMG and HWIL test bench design and fabrication. WP4 start was triggered by WP2 outputs (EMG specifications) and by partial results of WP3 (EMG prototype). The HWIL testing scheme has been developed integrating on the test bench the control systems defined in WP5 and numerical models developed in WP2. The bench has been developed by VGA and will be operated by UMBRA. In parallel, BV M&O will review all the documents and procedures to help in aligning them to the requirements of a future certification process.
WP5 – Control systems design and implementation
WP5, led by NTNU, used the EMG prototype system design parameters (defined in WP2) and physical constraints such as maximum torque, speed and stroke (derived from WP2 and WP3) as input in order to identify PTO control strategies that can optimize EMG overall power performance. Some control alternatives have been evaluated taking into consideration EMG efficiency at partial load. A number of representative test cases have been analysed, representing both steady state and typical operational transients to identify the most promising control strategy. All the simulation models will be implemented to ease the subsequent implementation in HWIL testing platform in WP6.
The IMAGINE project is related to the topic ―Developing the next generation technologies of renewable electricity and heating/cooling‖. Table 5 provides an overview on how this proposal addresses the expected impacts outlined in the corresponding Work Programme.
The TRL advancement of the EMG up to TRL 5 will take place through extensive modelling and testing activities in an established industrial facility, based on the implementation of interdisciplinary work packages developed by partners with cross-functional engineering skills. The HWIL testing scheme can dramatically reduce risks in view of later deployments at sea, anticipating WEC-EMG interaction and performance. The integration of the consortium competences and the cross-review of the project outcomes by the Technical Advisory Board will also mitigate risks for the successive progression of the EMG to higher TRLs.
The average efficiency of the EMG prototype is expected to be above 70% across a wide load range for all the emulated WECs, reaching values up to 85%. In addition, the EMG efficiency is expected to be nearly independent of the wave period and spectrum shape, with an expected deviation of ±5% from the average value, for a given wave height. This enhances the EMG flexibility in being suitable for a wide range of WECs and deployment sites.
The EMG, compared to state-of-the-art PTO systems for wave energy, sensibly reduces life-cycle environmental impact. Indeed, compared to hydraulic systems, the EMG uses no pressurized fluids thus avoiding risk of leakage during operation and simplifying disposal. Furthermore, compared to purely electrical systems, the EMG reduces the use of ferromagnetic materials thus reducing pollution impacts associated with extraction processes.
The TRL advancement of the EMG up to TRL 5 will take place through extensive modelling and testing activities in an established industrial facility, based on the implementation of interdisciplinary work packages developed by partners with cross-functional engineering skills. The HWIL testing scheme can dramatically reduce risks in view of later deployments at sea, anticipating WEC-EMG interaction and performance. The integration of the consortium competences and the cross-review of the project outcomes by the Technical Advisory Board will also mitigate risks for the successive progression of the EMG to higher TRLs.
The average efficiency of the EMG prototype is expected to be above 70% across a wide load range for all the emulated WECs, reaching values up to 85%. In addition, the EMG efficiency is expected to be nearly independent of the wave period and spectrum shape, with an expected deviation of ±5% from the average value, for a given wave height. This enhances the EMG flexibility in being suitable for a wide range of WECs and deployment sites.
The EMG, compared to state-of-the-art PTO systems for wave energy, sensibly reduces life-cycle environmental impact. Indeed, compared to hydraulic systems, the EMG uses no pressurized fluids thus avoiding risk of leakage during operation and simplifying disposal. Furthermore, compared to purely electrical systems, the EMG reduces the use of ferromagnetic materials thus reducing pollution impacts associated with extraction processes.