Tuesday, September 27, 2022

Young scientists, awarded the project of the magnet-free synchronous reluctance motor

The Regeneron International Science and Engineering Fair is a big international STEM competition of higher schools that takes place every year in the United States. In the last edition, the young scientists of higher schools worldwide won almost 8 million dollars in awards and scholarships.
Among them – obtaining a prize worth 75,000 dollars – there is also a student committed to a project whose mission is revolutionizing the world of electric motors. He is the seventeen years old Robert Sansone from Fort Pierce, in Florida. The teenager has already accomplished over 60 projects connected with the engineering world and today the focus is on his project to improve the synchronous reluctance motor, which can operate without magnets and without using rare earths.
We cannot reveal a lot because the technology is not patented, yet. However, we can say the teenager, not relying on many resources to implement advanced motors, has to manufacture a scale prototype by using a 3D printer and exploiting plastic. The delivered torque exceeds 39%, whereas efficiency is 31% higher at a rotation speed of 300 rpm. At 750 rpm, the efficiency has improved by 37%. Clearly, they are much lower rotation speeds than motors on trade because the prototype has not been brought to higher rotation rates to avoid overheating plastic components. Maybe that money won will allow him further developments.

Cues and inspirations by Muner University

The University can prove to be a hotbed able to make whole sectors evolve. It is always precious to underline the school’s key role, especially concerning STEM subjects that have the entire potential to improve the world. An excellent example is represented by Jacopo Ferretti, fresh graduate in Electric Drive Engineer during his master of Electric Vehicle Engineering at University of MUNER who has developed some cool University projects with the target of innovating in the ambit of electric motors.
«I was asked to analytically design two electric motors using Matlab, and to validate them using Finite Element Analysis, with FEMM». The motors under investigation were 28kW Induction Motor and 55kW Surface Permanent Magnet Motor.
«The main difficulty during this project was to use and to understand all the equation seen during the course. I have to admit that I spent a lot of time troubleshooting and understanding why my outputs were not so great! At least, it was a great experience and I have learned a lot of new things regarding EM that were unclear for me».
Recently, on Linkedin, the neo-engineer has made available his reports Induction and SPM motor design, Citycar comfort evaluation, comparing suspension in case of traditional and In-wheel powertrain, and Electromagnetic Compatibility,

The new generation of electric vans by Peugeot uses hydrogen

Among the first that have proposed a commercial electric van powered by hydrogen fuel cells as standard, Peugeot is more and more raising the bar. And it does it with the new e-Expert Hydrogen, compact van equipped with a next-generation technology called “Next gen e-Van Hydrogen efficiency”, enabling it to travel over 400 km at zero emissions, being recharged in less than 3 minutes.
Based on the EMP2 (Efficient Modular Platform) multi-energy platform, the PEUGEOT e-EXPERT Hydrogen is an all-electric vehicle, combining two on-board sources of electrical energy, thanks to STELLANTIS’ innovative “mid-power plug-in hydrogen fuel cell electric” system: the system combines a battery that can be recharged from the mains with the fuel cell powered by hydrogen contained in the canisters under the vehicle floor. The PEUGEOT e-EXPERT Hydrogen benefits from all the advantages of hydrogen, battery technology and electric traction.
Actually, it is the hydrogen version of its electric van with fuel cell technology by Stellantis.
The hydrogen-powered fuel cell is combined with a rechargeable lithium-ion battery with 10.5 kWh capacity and 90 kW power. Positioned under seats, the battery also supplies the electric motor during some driving phases.
An onboard 11-kW three-phase battery charger is used for the power supply. These two energy sources work in synergy to power a permanent-magnet electric motor, with 100 KW (136 HP) power that delivers 260-Nm torque.
Positioned on the front axle, this electric traction chain resembles the one of Peugeot e-Expert (electric battery model). The van features the same load volume characteristics as battery electric and diesel versions: up to 6.1mü of cargo volume, 1100 kg of payload, 1000 kg of towing capacity. The high-voltage battery is guaranteed for 8 years or 160,000 km, by at least 70% of its efficiency.

Electric motor with recycled magnets?

Im E-Scooter befindet sich der Elektromotor im Reifen: Die Magnete sind die silbernen Quader außen an den Kupferwicklungen.

Recycled magnets can be used to power motors in the electric mobility sector, without any power loss compared to new magnets. As proven by FunMAG project, developed by Fraunhofer Institut: «During the process, magnets absorb a bit of oxygen, which results in a slight deterioration of quality, but we can contrast it by adding from 10 to 20 percent of new material or by further processing magnets’ microstructure”, explained Konrad Opelt, project head and material scientist.
Neodymium-based magnets are the most powerful at disposal on the market and represent about half of motor’s costs because, as the name suggests, they contain rare earth elements like neodymium or dysprosium. The mining activity releases poisonous by-products that can pollute groundwater, causing damages to both people and to nature. Although the manufacturing process is expensive and problematic, magnets are generally rejected and melt together with steel scraps.
Nowadays researchers are working to optimize the treatment during the recycling process.

The influence of rotors bar form on SPIM performance

Mandatory regulations are published worldwide for the efficiency of line-operated electric motors. Compact single-phase induction motors (SPIMs) will not be spared in terms of effectiveness and efficiency, as new restrictions are set to be implemented no later than July 2023. As a result, the efficiency of capacitor-run SPIMs will be required to exceed (now) normal values and meet the standards of the IE3 performance class. Less consideration has been given to the influence of rotors bar form on SPIM performance and starting capabilities. It is a key topic that has been investigated by a recent study concerning the rotor squirrel-cage layouts with eight distinct bar forms, published on MDPI academic container.
The study is entitled “Effect of Rotor Bars Shape on the Single-Phase Induction Motors Performance: An Analysis toward Their Efficiency Improvement”, Energies 2022, with authors Chasiotis, I.D., Karnavas, Y.L., Scuiller, F.
The already published research works investigated several design, control, and manufacturing aspects. Nevertheless, less attention has been devoted to the study of the rotor bar’s shape impact, both on the SPIMs’ efficiency and starting capability. This gap is filled in this work by examining rotor squirrel-cage configurations with eight different bar shapes for the case of a four-pole/1.0 HP capacitor-run SPIM. A sensitivity analysis, which involves the simultaneous variation of the bar’s cross-sectional area, run-capacitor value, and auxiliary to main winding turns ratio, is performed. The motor’s electromagnetic behavior is estimated through finite element analysis. Through the acquired results, useful directions toward the SPIMs’ efficiency enhancement are provided, while simultaneously conclusions—not found elsewhere—are drawn concerning performance quantities, such as the motor’s starting current, currents shift angle, particular losses and breakdown torque.
The stator and rotor core of the SPIM are composed of thin laminae of electrical metals. The squirrel-cage of the rotor is manufactured of a conducting alloy by die casting. Because of its inexpensive cost, aluminium alloy is more commonly used in the fabrication of tiny SPIMs, and it provides for greater freedom in the design of the bar.

Three phase Induction motor and an SPM motor

Hussain Shafi, Electric Vehicle Engineering Student at UNIBO has published a project in the ambit of the course Electric Motor Design delivered by Prof. Giacomo Sala.
«In this report we have designed a 3 phase Induction motor and an SPM (Surface Mounted Permanent Magnet) motor both with different specifications. All the analytical equations are implemented in Matlab for preliminary sizing of motor and useful graphs while the FEA analysis is done using FEMM software which is an open-source software that can simulate the Electromechanical models. By using some additional libraries for Matlab, and it is possible to see how it is done in the report».
The project involves designing and sizing of SPM Motor and Induction Motor and the thermal aspects were also realized in this project.
A 3-phase induction motor is an electromechanical energy conversion device which converts 3-phase input electrical power into output mechanical power. A 3-phase induction motor consists of a stator and a rotor. The stator carries a 3- phase stator winding while the rotor carries a short-circuited winding called rotor winding. The stator winding is supplied from a 3-phase supply. The rotor winding drives its voltage and power from the stator winding through electromagnetic induction and hence the name. IMs are less expensive, do not suffer demagnetization, and they are often more reliable and simpler to manufacture as compared to SPM motors. The disadvantage of this motor typology is its insufficient performance in terms of efficiency and power factor.

Hpe Coxa, artificial intelligence laboratories to develop electric motors

About two years ago Hpe Coxa, company specialized in services of engineering, design and precision manufacturing for the sectors of automotive, motorsport, automation, aerospace and defence, inaugurated in Modena the two E LAB and Ai LAB laboratories that establish the company’s collaboration with the Universities of Bologna and Modena in the most advanced technological fields. In particular, E LAB, in collaboration with the University of Bologna and UniMoRe, has made students work at the design, engineering and implementation of an electric motor, supervised by “senior” engineers: in just nine months they have given birth to a unique item, the “demonstrator”. Today, they go on innovating in that direction and in Modena the excellence centre for the Artificial Intelligence is established, due to the collaboration between Hewlett Packard Enterprise and HPE COXA, further raising the bar of the development of solutions, including electric motors. This synergy will lead them to explore together the new opportunities of the data age for the industrial sector.
Combining design skills and competences that range from high-performance mechanical engineering to the most recent IT technologies, the two partners will develop a common ecosystem committed to innovation and based on Open Innovation principles.

How contrasting shaft current problems

The big player ABB is casting its spotlights on what are shaft currents and how to protect AC motor. Over time, continual arcing within an electric motor will cause damage to the surface of the bearing raceway resulting in vibration and heat, loud operating noises, and eventually motor failure.
Fortunately, there are several practical and easy ways to mitigate shaft current issues. Using proper VFD cables and bearing protection will help protect the life of your motor and driven equipment.
Brush protection rings and insulated bearings are just a few ways to mitigate shaft currents that can harm the motor and equipment. Including these preventive measures will ensure peace of mind and increase the reliability of your inverter duty motor performance.

Electric flying motorbikes. Science Fiction?

In the collective imagination, it is associated with futuristic unreal movies. It seems instead that the electric motorbike is not so distant thanks to Horizon Aeronautics that will release an electric hybrid eVTOL hoverbike with an innovative system of variable-pitch hemispherical rotor.
The Hoverbike by Horizon, with a design studied to grant significant efficiency rises, features the look of a jet ski and it is powered by a compact hybrid-electric system.
The technological collaboration was signed with the innovative Blainjett Aviation start-up, which works at the aerodynamic propulsion. The developed solution is called Dynamic Variable Pitch (DVP), patented technology of the hemispherical rotors that allows generating higher speeds with smaller sizes.
What is the gap that makes the difference? To generate the forward thrust, instead of adjusting the angle of attack of a helicopter or of an eVTOL rotor, the DVP adjusts the pitch of rotor blades on half of rotors’ arc.
Concerning its overall dimensions, the aircraft will weigh about 380 kg and the sizes will be 2.70 metres per 1.20 metres, able to host from one to three passengers on board.

A super electric motor incoming

Winding-free, featuring excellent performances, low weight and volume. Here are the main features of the new motor at which is working the Emilia company Poggipolini, top player in titanium fasteners for Formula Uno and aerospace. The new motor will address aerospace and defence, but also the world of the electric traction for Motor Sport and high-end cars.
Concerning this, a key role will be played by the factory of the future “Speed Up Lab”, headquartered in the new factory at San Lazzaro di Savena, in an area of over 20,000 sq. m., close to the Manufacturing Center of Excellence inaugurated in 2019. Its mission is working in open innovation.
Recently, the company has established a partnership with Puglia startup Roboze to design and to manufacture the mechanical parts of electric motors, 3D printed with innovative materials such as Carbon Peek, a carbon-reinforced polymer. The collaboration will aim at accelerating the adoption of this new process technology, shifting from engineering to industrialization.
The technology of the new electric motors will be fully innovative and will precisely concern its operation, as well as materials, which will assure lower weight and simplification of architectures and manufacturing processes.