In the past, various companies have already tried developing disruptive zero-emission motors, for instance with motors hidden in the wheel. This frontier has not technically found its benefit, yet, especially owing to the weight hindrance.
Hitachi, more precisely its subsidiary Hitachi Astemo, is trying giving a solution to the problem with the Direct-Drive. In practice, the manufacturer is going to integrate everything in a single component, placing in the wheel the motor, the inverter and the brake to achieve a power/weight ratio of 2.5 kW for each kg. In this way, they can partially eliminate wirings, as well as transmission gears, so improving efficiency up to 30%.
The prototype wheel is 19″, with maximum torque of 960 Nm, operation at 420 volt and maximum power of 60 kW: multiplied by four wheels, the total value would amount to 240 kW.
To avoid undesired contacts between the inverter components and the liquid, the cooling oil circulates in a ring among the various parts, by means of tubes, directly acting on power semiconductors, and then it is conveyed to the motor to cool coils.
Motor in the wheel? Here is the proposal by Hitachi
Electric Motors Efficiency needs better copper
A new manufacturing process yields highest conductivity copper composites at bulk scale. This is a discovery of researchers at Pacific Northwest National Laboratory (PNNL): they have increased the conductivity of copper wire by about five percent. Higher conductivity means that less copper is needed for the same efficiency, which can reduce the weight and volume of various components that are expected to power our future electric vehicles.
The laboratory teamed with General Motors to test out the souped-up copper wire for use in vehicle motor components. As part of a cost-shared research project, the team validated the increased conductivity and found that it also has higher ductility-the ability to stretch farther before it breaks. In other physical properties, it behaved just like regular copper so it can be welded and subjected to other mechanical stresses with no degradation of performance. This means that no specialized manufacturing methods are necessary to assemble motors-only the new advanced PNNL copper composite.
The technology can apply to any industry that uses copper to move electrical energy, including power transmission, electronics, wireless chargers, electric motors, generators, under-sea cables, and batteries.
General Motors Research and Development engineers verified the higher conductivity copper wire can be welded, brazed, and formed in exactly the same way as conventional copper wire. This indicates seamless integration with existing motor manufacturing processes.
«To further lightweight motors, advances in materials is the new paradigm – said Darrell Herling of PNNL’s Energy Processes and Materials Division. Higher conductivity copper could be a disruptive approach to lightweighting and/or increasing efficiency for any electric motor or wireless vehicle charging sytem».
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,
Saietta: axial flux electric motor to electrify the world mobility
It is headquartered in the United Kingdom and it develops in pioneering way solutions for the automotive electrification and it is particularly in turmoil precisely for the great boom that the segment of electric vehicles is living, also due to the legislator’s contribution. We are speaking of Saietta, in search of new 250 collaborators and that has recently released its latest project: axial flux electric motor design, which combines both distributed windings with a yokeless stator.
Besides, the moment is particularly favourable: it has won a research contract through the Advanced Propulsion Center (APC) of the United Kingdom, but the witness by the chief executive officer of Saietta Group, Wicher Kist, a bit slows down enthusiasms: «We are ready for the future of transportation by stepping in with modern, lightweight electric motors as traditional internal combustion engines fuelled by petrol and diesel reach the end of the road. If the 2030 target is to be met, key decisions on future investment will need to be made quickly so companies like ours realize our full potential. That means more funding from UK government and quickly».
The company aims at a modular approach to its motors that are at the service of a broad range of vehicles, from scooters to trucks. Its first offer of commercial motors, for instance, AFT140, is optimized for the use of medium-size bikes and vehicles for last-mile deliveries, currently much more important solutions in terms of volumes in Asian markets rather than in Western ones. Precisely in this scenario, Saietta has recently announced a remarkable partnership agreement with Padmini VNA, one of the main automotive players in India.
The commercial agreement provides for Padmini collaboration with Saietta to develop new opportunities in the Indian market and renowned Indian two-wheel OEM players stand out among its customers, such as Hero MotorCorp, TVS, Bajaj Auto and Royal Enfield.
University, an infrastructure to experiment new electric vehicles
University constantly operates in the research and development of an electric future. A scenario that frames also Turin Polytechnics, which has recently presented the CARS-HEV infrastructure for the experimentation of conventional, hybrid and electric vehicles implemented by CARS Inter-department Centre and co-funded by Piedmont Region through European Funds. Everything was presented during an event organized by the Polytechnics in collaboration with FPI Fondazione Piemonte Innova, Mesap, Pole of Mechatronic Innovation and Advanced Manufacturing Systems and AVL Italy.
During the meeting, they described the activity of the Center for Automotive Research and Sustainable Mobility CARS and of the innovative test chamber Hybrid/Electric powertrain and Vehicle Test Facility and they presented as best practices the collaborations with JRC-Joint Research Center, with Stellantis and with AVL.
The infrastructure allows carrying out the test cycles demanded by international regulations, in addition to non-standard drive cycles, like those acquired by the experimentation on the road to validate control strategies of the energy management system, measuring consumptions, efficiency and emissions.
Professor Matteo Sonza Reorda, Vice-Rector of Research for Polytechnics, stated: «Turin Polytechnic, with this new forefront structure has succeeded in orienting the available resources at best, seizing the opportunities offered by INFRA-P announcement by Piedmont Region to support the implementation of new open-access research infrastructures, through which boosting territory’s socio-economic development according to a cooperation between public and private»
Test benches for engineering students to asses industrial electronic equipment
The University of Southern Denmark gives young engineering students an opportunity to be part of developing the green technology of the future in a creative study environment with modern teaching facilities and dedicated teachers.
The engineering students are taught electronics and challenged with real-life industrial equipment driven by electric motors and drives manufactured by Nidec.
As part of the teaching projects, the institute and the students have access to several advanced electronic test benches, which gives them a good insight into the handling, testing and research of different combinations of industrial electronic equipment and teaches them to test torque, speed, load, etc. under realistic conditions.
The test benches use Nidec Leroy-Somer motor units (servo motors, LSMV and IMfinity induction ranges) and Control Techniques Unidrive M600/M700 drives and combine different set-ups of advanced variable speed drives and high-tech electric motors, which have the flexibility to test a wide variety of electronic equipment.
Each semester, the electronic engineering degree programme includes project work on a current topic, for example how to design the electronic controller of an electric go-kart motor.
In connection with the project, the students have access to a genuine go-kart with an electric motor as well as a corresponding test bench with programmable drives and electric motors.
Regal’s edge product tools
Regal Beloit Corporation, specialized in the engineering and manufacturing of high-efficiency electric motors and power transmission products, has recently announced its enhanced Power Transmission Solutions (PTS) Edge tools. Regal’sEdge tools include product selection modules for belt drive, bearing and gearing products and mechanical power components, as well as bearing registration and a belt drive efficiency calculator. These improved Edge tools are easier to use, mobile-friendly and fully integrated to the regalbeloit.com online product catalogue.
Edge product selection modules assist users in selecting the right power transmission mechanical components based on their specific application requirements. Once they install new bearings products, the bearing registration allows users to not only register their bearings but also manage assets on the Regal PT mobile app. The belt drive efficiency calculator helps users to calculate how much money they can save on energy consumption by using Browning™ belt drives.
«The enhanced Edge tools – said Matthew Clemens, DCX marketing specialist at Regal – allow a mobile friendly, integrated customer experience across regalbeloit.com. The modules have been updated to help point customers to common parts, versus made-to-order parts, so the primary selections are readily available».
Here is the hybrid tractor for agriculture
It is called REX4 Electra the hybrid tractor by Landini brand, trademark of Argo Tractors Spa company, multinational of Argo industrial Group headquartered at Fabbrico, in Reggio Emilia province.
The vehicle, intended for crossing fruit and vegetable fields in a sustainable way, has won the Technical Novelty Eima International, too.
Propulsion is dominated by the 110 HP diesel engine that, through the generator and the battery, powers the two front electric motors, which deliver 12-kW power that can rise to 16-kW for each wheel.
In REX4, the novelty is positioned in the “bow” of the tractor, with fully electric front-wheel drive on suspended axle and sensors, electronic controls, generator and battery dedicated to the Brake Energy Recovery, the energy recovery in braking and deceleration phases.
The system, which is called Electra Evolving Hybrid, is managed by PMS, Power Management System, which supervises the operation of all devices, battery included.
What are benefits in terms of performances? We will achieve the 10% fuel saving, the 15% steering angle improvement, the 15% vibration reduction and higher transport stability.
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.
A new generation of high-performance e-motor, for braking systems and cars’ traction
Developing a new generation of high-performance electric motors, for both braking systems and cars’ traction, was the goal of Inproves pilot project, started in 2017, whose head company is Brembo, top player multinational in the production of systems for braking plants. Together with it, the partners eNovia, Mako-Shark, Magnenti Marelli, Motorsport, Peri, Milan Polytechnics, – Engineering and Energy Departments, MDQuadro, UTPVision and University of Bergamo have collaborated in the initiative.
We are in the ambit of the 2014-2020 operational regional programme, co-funded by Lombardy Region with European funds.
Inproves has provided for an integration of product and process for the implementation of road vehicles’ electric motors, to develop brushless electric motors (Permanent Magnet Machines-PMM) for both braking systems and for traction and energy recovery.
Such PMM are conceived simultaneously with the manufacturing process, based on Industry 4.0 paradigms, that is to say the complete digitalization of the production process, for the control and the management of plants, of processes and of logistic-productive flows.
Brembo and Marelli, with the support of Milan Polytechnics, have developed the mechanical and electromagnetic design of two different motor typologies for braking and traction systems.
Marelli has implemented a new high-efficiency traction motor, whereas Brembo has started the production of two motors’ prototypes for braking systems of different sizes, through a new digitalized assembling line, collaborating also with e-Novia, the Business Factory specialized in deep technologies, to develop a demonstrator of a new concept of integrated sensor for the control of the braking system. More in detail, concerning e-Novia, it is the design and testing of a magnetic sensor for measuring the rotor’s absolute position in a BLDC motor, with advantages in terms of assembling and performances.
«With INPROVES, today an ambitious challenging project is ending,” stated Alessandro Ciotti – Chief R&D Officer of Brembo, “which has involved the pre-industrial development of a new family of products and technical solutions in the ambit of the sustainable mobility of the future, whose priority targets are the adoption of more efficient, automated and connected vehicles».