Periodic Reporting for period 2 - MAGLEV (Measurement and Analysis of Generator bearing Loads and Efficiency with Validation) Reporting period: 2020-11-01 to 2022-11-30 Summary of the context and overall objectives of the project Bearings are highly engineered, precision-made components that enable electric machines (such as motors and generators) to move at high speeds and carry remarkable loads with high efficiency. The EU-funded MAGLEV project designed and built a test rig for the Bearing Relief Generator (BRG) that reduces generator whirl and vibrations, enabling operation at higher power densities and efficiencies compared to existing solutions. MAGLEV’s cutting-edge methods promise to change the electrical machine scene and enhance EU’s competitiveness in the field.The Clean Sky 2 project (MAGLEV) objective made a significant contribution to the new class of bearing relief generators. This contribution was developed by building a demonstrator machine. Technical methods were developed to reduce misalignment and vibration of the generator, and thus enabling operation at higher power density and efficiency compared to the existing solutions.MAGLEV included challenging tasks such as measuring shaft instantaneous position and bearing loads accurately in dynamic operating conditions and at high speed, developing a control technology to emulate the loads on the generator with a bearing relief system, the commissioning of the demonstrator machine, obtaining test data, and validating the simulation results with test data.The key objective of this project was to measure the reduction in load and drag from application of the bearing relief technology. The objective was not fully achieved by the end of the project due to a shortage on power electronics components of the designed inverter. However, it will be fully achieved once the inverter is available and a the testing can be completed to obtain a full set of test data. The magnitude of this reduction in load and drag will indicate the technical advantages of the design of the BRG and thus indicate success for the BRG technology as a whole in supporting its ambition towards the larger industry goal of SYSTEMS ITD as a part of the Clean Sky 2 programme. Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far A BRG arrangement has been developed including shaft position (displacement), temperature, speed and acceleration measurement on the generator. Load units have been designed to apply and control external loads. Overall, a highly capable and highly integrated test rig arrangement has been designed, manufactured, built and commissioned. The simulation chain has been developed and applied. A bearingless test option with x-y force measurement has been developed, simultaneously measuring bearing load and displacement, enabling the full validation of the electro-mechanical simulation chain. In addition, to the investigations at the Topic Leaders site, bearing tests were performed at WZL of RWTH Aachen to validate the bearing friction under radial load. A new concept was developed to measure the friction of the generator bearings under radial load and a corresponding test rig setup was designed, manufactured and finally tested on spindle bearings. All of this provided the Topic Leader, the University of Nottingham with a highly capable test rig that allows it the freedom to investigate and demonstrate the capabilities of the exciting technology of the Bearing Relief Generator and to develop it further. The test rig was commissioned successfully and it was confirmed by testing that the test rig met the requirements set by the Topic Leader for testing the radial force control technology. The replacement inverter used for the tests had a significantly lower power capability (compared to the designed inverter), so only relatively small forces could be applied. However, it was demonstrated that the forces applied by the inverter and the corresponding change in displacement can be measured and thus the test setup is working stable with a sufficiently high resolution, capturing these rather low forces and displacements. Once the designed inverter is available testing across the full operation envelope will be conducted, and the test results will be used to fully validate the developed simulation tool chain and to quantify the benefits of the BRG technology.Three journal papers and one conference presentations have been published in relation to the project, as well as several work shop contributions. A further two conference presentation abstracts were accepted and three journal papers are currently in the submission and review process. A full set of test results will be obtained and will enable both the quantification of the BRG performance and benefits and the validation of the developed simulation tool chain. These data are crucial for both the Topic leader and the consortium for exploitation. The exploitation is by no means restricted to the aerospace industry, the automotive (for electric vehicles) and power generation (high-speed applications) industries also look promising. Furthermore, the application in the manufacturing industry, by both WZL of RWTH Aachen and Romax/Hexagon Manufacturing Intelligence, specifically machine spindle applications will be exploited. The active control of the spindle stiffness and therefore the cutting force generation can be utilized to improve surface quality, reduce tool wear and extend spindle life. Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far) The Bearing Relief Generator (BRG) is intended to achieve higher power density, speeds, reliability and efficiency than conventional generators. Additionally, various technobricks that have been used to build the capability for the design and simulation of the BRG have their own merit in isolation. The understanding of the drag and skidding of rolling element bearings at high speed is a challenge standing in the way of greater take up of high speed, power dense electric machines in electric vehicles, and this project will assist this, yielding environmental and societal benefits. The integrated simulation of control-electrical-mechanical systems has uses in many applications, so similar benefits may also arise in other industries and applications, including electric vehicle powertrains, power generation, machine spindles etc.Lower environmental impact (lower CO2 and/or less noise) is achieved both through making electric machines more competitive in the applications where they are not necessarily used currently, and in making them quieter, more efficient and more durable in the applications where they are currently used. The mproved generator drive system performance in terms of higher efficiency and durability also provides socio-economic benefits and the reduction of shock loads on generator bearings also provides safety benefits. This is all supporting the Clean Sky 2 ambition of a strong, globally competitive aeronautical industry and supply chain in Europe, by accelerating the adoption of new technology into the global fleet Bearing Relief Generator on test rig Bearing Relief Generator on test rig with component naming, including cross section of the load unit MAGLEV project structure and Work Packages
