The electric vehicle (EV) revolution is in full swing, and at the heart of this transformative shift lies the remarkable evolution of electric motor technology. From their humble beginnings, electric motors have made astonishing progress, driving profound advancements in the performance of electric vehicles. In this article, we’ll delve into the captivating ways in which electric motor technology is reshaping the landscape of EVs. From heightened acceleration and efficiency to reduced maintenance and far-reaching environmental benefits, let’s explore how these motors are propelling the future of transportation.
Even the aviation industry, responsible for a substantial portion of global carbon emissions, is embracing electric motor technology to usher in change. The quest for reduced emissions and enhanced aircraft performance is steering aviation toward more electric aircraft (MEA), paving the way for all-electric flight. Simplified propulsion, where batteries power electric motors to spin propellers, is challenging the conventional norms of aviation and charting a new course toward a more sustainable future.
Electric Motors: EV Powerhouses
At the heart of every EV lies the electric motor, a pivotal component that replaces the traditional internal combustion engine. Compared to their gasoline counterparts, electric motors are compact, lightweight, mechanically simpler, and offer instantaneous torque at any speed. This means EVs can achieve exceptional acceleration and responsiveness. Moreover, electric motors boast superior overall efficiency, generating less heat and yielding reduced energy wastage.
An electric motor is an electrical machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor’s magnetic field and electric current in a wire winding to generate force in the form of torque applied on the motor’s shaft.
Electric motors can be powered by direct current (DC) sources, such as from batteries, or rectifiers, or by alternating current (AC) sources, such as a power grid, inverters or electrical generators. An electric generator is mechanically identical to an electric motor, but operates with a reversed flow of power, converting mechanical energy into electrical energy.
Electric motors produce linear or rotary force (torque) intended to propel some external mechanism, such as a fan or an elevator. An electric motor is generally designed for continuous rotation, or for linear movement over a significant distance compared to its size. Magnetic solenoids produce significant mechanical force, but over an operating distance comparable to their size.
Electric Motor types
Electric motors exhibit diverse classifications based on power source type, internal construction, application, and motion output. Beyond the distinction between AC and DC types, motors can be brushed or brushless, possess various phases (single-phase, two-phase, three-phase), and be either air-cooled or liquid-cooled. They cater to a wide array of purposes, from general industrial use to monumental tasks like ship propulsion and energy storage. Here’s a glimpse into some key electric motor types:
1. DC Series Motor: These motors are characterized by high starting torque, making them ideal for traction applications. They were widely used in early 1900s traction systems. While offering easy speed control and the ability to handle sudden load changes, DC series motors have drawbacks such as high maintenance due to brushes and commutators.
2. Brushless DC Motors (BLDC): Distinguished by their permanent magnets and lack of commutators, BLDC motors ensure maintenance-free operation. They excel in applications demanding high starting torque and efficiency around 95-98%. BLDC motors are favored for electric vehicles due to their exceptional traction characteristics.
3. Permanent Magnet Synchronous Motor (PMSM): PMSM, commonly used in servo applications, relies on powerful permanent magnets for its rotor. It shares traction attributes with BLDC motors, including high power density and efficiency. PMSM offers higher efficiency compared to induction motors but often requires a variable speed drive for optimum performance.
4. Three Phase AC Induction Motors: Induction motors lack high starting torque under fixed voltage and frequency conditions. However, control techniques like FOC or v/f methods can modify this characteristic, rendering them suitable for traction. They are durable and can achieve efficiency levels of 92-95%. Complex control and inverter circuitry are challenges associated with induction motors.
5. Switched Reluctance Motors (SRM): SRMs are brushless DC motors providing continuous torque. Simple in construction and robust, they are characterized by a piece of laminated steel as the rotor. SRMs are poised to replace induction motors in variable speed applications due to their high power density and cooling efficiency.
6. Copper Rotor Motors (CRM): Copper rotor motors leverage copper rotor technology to enhance energy efficiency while retaining a compact footprint. These motors have gained prominence in various applications, including electric vehicles. The use of copper rotors enables efficiency gains and can be applied to both new installations and retrofit projects.
Electric motors encompass an impressive array of types, each with unique characteristics catering to specific applications. From high starting torque of DC series motors to the efficiency advantages of PMSM and the innovation of copper rotor technology, the electric motor landscape is a testament to continuous evolution and the pursuit of enhanced performance.
Revolution in Airframe Systems
Electric power is revolutionizing airframe systems, trimming fuel consumption and operational costs. The lightweight and compact nature of electric motors, coupled with their reliable performance, allows for increased power output without compromising efficiency. Notably, electric motors excel in applications where efficiency and reliability are paramount, as demonstrated by their integration into aviation systems.
Unveiling Energy Efficiency Potential
A recent whitepaper by ABB underscores the role of high-efficiency motors and drives in curbing energy consumption. These technologies have the potential to reduce global electricity consumption by up to 10%. The industrial sector, a significant energy consumer, can benefit immensely from these advancements. Industries and buildings together account for a substantial share of global energy use, and the adoption of high-efficiency motor technologies can contribute significantly to energy conservation and combating climate change.
Electrification of Aircrafts, vehicles etc. is based on three main pillars: batteries, electric motor and the powertronics [the power management system]. The rapid development in the field of Power electronics and control techniques has created a space for various types of electric motors to be used in Electric Vehicles. The electric motors used for automotive applications should have characteristics like high starting torque, high power density, good efficiency, etc.
Traditionally DC motors, have been prominent in EV propulsion. Their control principle is simple. However, the principle problem of DC motors arises from their commutators and brushes, which makes them less reliable and unsuitable for maintenance-free operation. Recent technological developments have pushed AC motors to a new era, leading to take definite advantages over DC motors: higher efficiency, higher power density, lower cost, more reliable, and almost maintenance free. As high reliability and maintenance-free operation are prime considerations in EV propulsion, AC induction motors are becoming attractive.
Advancements in Control
Modern control strategies have ushered in a new era of precision and efficiency in motor operation. Model-referencing adaptive control, variable structure control, and neural network control, among others, are redefining how electric motors are managed. Powerful microelectronic devices are essential for implementing these advanced control techniques, enabling fine-tuned and adaptive motor performance.
Innovative Cooling Solutions
Innovation is not limited to performance enhancements alone; it extends to novel cooling solutions that optimize motor operation. Equipmake’s inventive approach, arranging magnets in a wheel-like pattern, improves both torque and cooling. This 3D-printing-enabled design allows for effective heat dissipation, addressing a common challenge in electric motor technology.
Selecting the Right Motor for EVs
Selecting the ideal electric motor for EVs involves meticulous consideration of performance requirements, operating conditions, and associated costs. Different applications demand different motor types, such as BLDC hub motors for low-performance vehicles, and PMSM or induction motors for high-power applications. As synchronous reluctance and switched reluctance motors become cost-effective alternatives, the options for EV motor types continue to expand.
The electric motor market is expected to grow from an estimated USD 113.3 billion in 2020 to USD 169.1 billion by 2026, at a CAGR of 6.9% during the forecast period. The use of electrical equipment and machines in different industries and the renewables sector are major factors driving growth in the electric motor market. Rapid technological advancements have been playing an imperative role in the growth of the market. Further, improved insulation and operational efficiency have significantly improved the electro-mechanical machines in terms of safety and functionalities, leading to increased demand across multiple industries. Electric motors are used in multiple applications across industry verticals such as home appliances, industrial machinery, and vehicles. The market is expected to witness high growth from Heating, Ventilation, and Cooling (HVAC) applications as they are an inseparable component of HVAC equipment.
COVID-19 Impact on the Global Electric Motor Market
The most significant near-term impact on electric motors that are already contracted or in the manufacturing process will be felt through supply chains. Industry executives are anticipating delivery and construction slowdowns, either because nations have shuttered industries to slow the spread of coronavirus or because the workers have tested positive. Many components and parts for manufacturing electric motors come from China, the US and some parts of Europe. Manufacturing disruptions in China and the US could contribute to a significant fall in the electric motor market over the next one or two years.
Due to the COVID-19 pandemic, local currencies of many countries have depreciated. There is misalignment of supply and demand, leading to financial losses for components/parts manufacturers. Key components used in manufacturing electric motors are typically procured in US dollars, which results in increased component cost
Electric Motor Market Dynamics
Driver: Increased demand for HVAC systems in residential, commercial, and industrial end-users
Heating, ventilation, and air conditioning (HVAC) systems provide thermal comfort and ensure the air quality in indoor spaces. They are one of the core building blocks of modern infrastructures, especially for large office buildings or shopping malls. Electric DC motors are widely used in HVAC systems to achieve high efficiency in airflow systems and maximize their life and power. The demand for HVAC systems is increasing in Asia Pacific, especially in China and India, owing to the continuous growth in their industrial and commercial sectors. According to a report by Timetric Construction Intelligence Center (CIC), a market intelligence company, ~USD 1.08 trillion is expected to be invested in the global construction sector, especially for the development of industrial buildings during the next four to five years
Restraints: Fluctuating prices of raw materials from China
The prices of raw materials such as permanent magnets, steel bars, copper wires, and precision thin metals such as specialty alloys, which are used to make electric motors, are controlled by a few manufacturers in China. There is not much product differentiation and the price of the product determines the dominance of certain suppliers in the market. The resulting price fluctuations have to be borne by the other manufacturers/suppliers in the market. For instance, when manufacturers and suppliers face fluctuations in the prices of rare-earth permanent magnets during the manufacturing processes, they are unable to pass the price change to end-use customers. Hence, the profit margins of raw material suppliers are negatively affected.
Opportunities: Transition of global automotive industry toward electric vehicles
The global automotive industry is transitioning toward electric mobility with significant changes in electric vehicle technology. In Europe, the proactive measures taken for the decarbonization of society are leading to the increased adoption of electrical vehicles that use electric motors. Advancements in battery technologies have lowered battery costs and improved their charging speed. Increasing government support in the form of tax redemptions and incentives to promote eco-friendly electric vehicles that use electric motors are also acting as opportunities for the growth of the electric motor market. According to IEA, China is expected to account for 50% of the global passenger electrical vehicles by 2025.
Challenges: Easy availability of low-quality and inexpensive electric motors
The electric motor market is highly fragmented, featuring a large number of local and international players. Product quality is a primary parameter for differentiation in this market. The organized sector in the market mainly targets industrial buyers and maintains excellent product quality, while the unorganized sector offers low-cost alternatives to tap local markets. Local manufacturers of electric motors in most countries target the unorganized sector and compete strongly with the global suppliers in the respective markets. Leading market players are currently exposed to intense competition from such unorganized players supplying inexpensive and low-quality electric motors. This acts as a key challenge for the growth of the market.
Electric motors are of 3 types, namely AC, DC, and hermetic motor. Among these, the demand for AC motors has been the highest in the past, and the situation is likely to remain the same in the years to come as well. AC motors have higher speed and torque as compared to other variants and they are able to function at higher voltages. In addition this, AC motors are easier to maintain than DC and hermetic motors.
The AC motor type held the largest share in 2020. It is estimated to generate over USD 166 billion by 2028 due to the extensive use of AC motors in various applications ranging from irrigation pumps to modern-day robotics.
AC motors are further of two types, namely synchronous and induction, between which, a larger demand was created for induction AC motors in the past. Three-phase induction motors are highly popular in a number of industrial applications. Single-phase induction motors are utilized commonly in household applications, including grinders, pumps, mixers, fans, and washing machines. It is owing to such wide range of applications of induction motors that their demand is rising at a rapid pace.
By output power
The fractional horsepower (FHP) output segment represented over 87% of the overall market value in 2020. Fractional horsepower motors are used widely in all household appliances ranging from vacuum cleaners to coffee machines to refrigerators
The above 1 hp motors segment segment is expected to lead the electric motor market from 2020 to 2026. Electric motors are used in various end user applications owing to their compactness, light weight, and low maintenance requirements. The installation of electric motors in industrial and transportation end user applications is expected to show high growth.
The motor vehicles segment is the most prominent application segment, commanding more than 40.0% of the overall market value in 2020. The electro-mechanical machines are also extensively used in heavy industrial equipment as well as agricultural machinery
By industrial segment, by end-user is expected to be the largest contributor in the electric motor market during the forecast period.
The industrial segment is expected to lead the electric motor market from 2020 to 2026. This sector provides good scope for motor manufacturers, as most industries depend on motorized automation. The segment includes the utilities, oil & gas, cement & manufacturing, metal and mining, oil & gas, renewables, petrochemicals & chemicals, water & wastewater, and paper & pulp industries, all of which use electric motors for pumps, boilers, compressors, and other applications, at various process stages.
By rotor type, the inner rotor segment is expected to be the largest contributor during the forecast period.
The inner rotor segment is estimated to grow at a faster rate from 2020 to 2026. In inner rotor type motors, rotors are positioned at the center and surrounded by stator winding. These motors are used in the manufacturing, automotive, and consumer electronics industries for robotics, CNC machines, automatic door openers, and metal cutting and forming machine applications. These applications require motors that can carry out fast acceleration and deceleration of speed, offer high starting torque, have reversible action capability, and are compact. According to the IEA, EV Outlook 2020, the global sales of electric cars reached 2 million in 2019, 40% higher than in 2018. This indicates the increased demand for electric vehicles and their accelerated manufacturing in coming years, which in turn, is expected to fuel the demand for inner rotor electric motors.
The motor vehicles segment is the most prominent application segment, commanding more than 40.0% of the overall market value in 2020. The electro-mechanical machines are also extensively used in heavy industrial equipment as well as agricultural machinery
Asia Pacific is expected to be the largest electric motor market during the forecast period. Asia Pacific comprises China, India, Japan, South Korea, Australia, and Rest of Asia Pacific. Asia Pacific region held the largest revenue share in the electric motor market in 2020 and is projected to witness the fastest CAGR of 7.8% from 2021 to 2028. The growth can be attributed to increasing industrialization investments in countries such as China, India, South Korea, and Australia.
With the rapid industrialization, the countries in Asia Pacific are moving toward internet-based industrial operations in each sector. According to the GSM Association, the developed countries in Asia Pacific, such as South Korea, Japan, and Australia, are increasingly exploring the potential of innovative services and connected devices. The automotive sector in the region is also booming. Asia Pacific is the largest producer of automobiles in the world. In 2018, the region manufactured more than 50 million commercial vehicles. These factors are expected to drive the growth of the market in Asia Pacific
Further, the scope for market growth in the region is expected to increase significantly over the coming years, owing to the evolving agriculture sector through efficient irrigation practices and technology transfer.
The industry is characterized by regulatory policies and government initiatives that promote energy efficiency in machines and equipment. High-efficiency and output, low power consumption, increased operational life, and low maintenance costs are essential requirements for the electro-mechanical machines. Notably, technological innovations have introduced improved design, components, and motor specifications resulting in fulfillment of end-user requirements. Innovations and evolving policy frameworks are crucial for industry development and will play a key role in fueling the demand for the products over the forecast period.
In March 2020, Wolong Electric, a subsidiary of Wolong, acquired GE’s small industrial motors business for USD 160 million. This acquisition is expected to help Wolong gain a leading position in terms of market share
In February 2020, Nidec Corporation launched two new traction motor systems — the 200 kW Ni200Ex and 50 kW Ni50Ex — based on the company’s original 150 kW E-Axle (fully integrated traction motor system with an electric motor, reduction gearbox, and inverter).
In October 2019,WEG installed a low voltage electric motor plant in Hosur, India. The new 13,000 square meter facility is capable of producing 250,000 electric motors per year.
In May 2019, Allied Motion Technologies introduced the EnduraMax 75i Series, brushless DC motor with an all-digital integrated drive. The EnduraMax 75i Series brushless DC motor is used in a wide range of commercial/industrial applications including AGV vehicle traction or steering, medical patient-handling equipment, rotary/linear actuators, pumps, mobile HVAC blowers, and material handling systems.
In January 2018, TECO Westinghouse (Canada), a subsidiary of TECO Electric & Machinery, announced a new distribution partnership with Westech Industrial. This new partnership is likely to help TECO Westinghouse (Canada) gain access to new and uncharted markets in Canada.
Key Market Players
ABB (Switzerland), Siemens (Germany), Nidec Corporation (Japan), Wolong (China), and WEG (Brazil). These companies adopted expansion strategies and used mergers & acquisitions to gain traction in the electric motor market.
In High-Speed Motor Market, some of the Leading Companies are: Xoar International LLC (The U.S.); EMRAX d.o.o. (Slovenia); Windings Inc. (The U.S.); ARC Systems Inc. (The U.S.); Siemens (Germany); Safran Electrical & Power (France); MagniX (The U.S.); MGM COMPRO (Czechia); H3X Technologies Inc. (The U.S.); NEMA Ltd. (The U.K.); Allied Motion Technologies (The U.S.); Meggitt PLC (The U.K.) and Pipistrel (Slovenia)
An Ever-Evolving Landscape
The world of electric motor technology is an ever-evolving landscape that holds promise for a sustainable and efficient future. From aerospace to electric vehicles, these motors are paving the way for innovation, reliability, and environmental stewardship. While challenges persist, visionary startups like H3X are rewriting the rules, pushing the boundaries of power density, integration, and efficiency.
Motor and drive technologies have seen advancement in the past decade, with today’s designs delivering energy efficiencies. However, a significant number of industrial electric motor-driven systems in operation today — in the region of 300 million globally — are reportedly inefficient or consume much more power than required, resulting in energy waste. Independent research estimates that if these systems were replaced with optimized, high-efficiency equipment, the gains could reduce global electricity consumption by up to 10%. In turn, this would account for more than 40% of the reduction in greenhouse gas emissions needed to meet the 2040 climate goals established by the Paris Agreement.
Airbus has also been collaborating with Rolls-Royce to co-develop E-FanX, their hybrid aircraft that will be driven by a 2-megawatt electric motor. Aviation high-speed motor systems are set to play a central role in providing the necessary propulsion power to these electric-based airplanes due to their reliability and ability to work in conjunction with electrical units.
H3X: Revolutionizing Electric Motors for Power and Efficiency
Startup company H3X is aiming to revolutionize electric motors with an integrated design that claims to outperform existing market options. As the energy demands for aircraft propulsion increase exponentially with size and mass, H3X aims to address this challenge by creating a highly efficient and compact electric motor.
The improvement of electric flight mainly hinges on enhancing either batteries or motors. H3X asserts that their breakthrough in power density, surpassing competitors by approximately 300%, could potentially open up new industries. While a 10-20% improvement in power per kilogram is significant, H3X’s motor has achieved a remarkable threefold performance increase.
Unlike traditional electric motor setups with separate components for the motor, power delivery, and gearbox, H3X’s design is fully integrated. This integration optimizes the synergy between materials, manufacturing, and electric components, allowing them to work cohesively within the same housing. The shared cooling infrastructure, enabled by advancements in power switching hardware, is enhanced further by novel pure-copper 3D-printing techniques.
H3X’s integrated motor, the HPDM-250, is notably smaller than many competitors while generating significantly more power. While the advanced techniques used might suggest increased costs, the compact size and integrated design actually lead to savings in terms of cost, time, and material.
Although servicing an integrated motor is more intricate compared to off-the-shelf motors, H3X has carefully considered maintenance from the outset. Their motor’s servicing complexity lies somewhere between traditional electric and gas-powered motors.
While the highly regulated aviation industry presents challenges, H3X is targeting smaller, less-regulated sectors that can benefit from improved electric propulsion. Applications such as cargo drones, electric boats, and air taxis stand to gain significantly from increased motor power and efficiency, potentially moving these technologies from niche to mainstream status.
MIT Engineers Develop 1-Megawatt Electric Motor for Aircraft Electrification
A team of MIT engineers has designed a 1-megawatt electric motor that could play a crucial role in electrifying larger aircraft, such as commercial airliners. The team has successfully tested the major components of the motor, demonstrating that they can work together to generate one megawatt of power at a size and weight comparable to small aero-engines.
The electric motor is intended for hybrid or turbo-electric propulsion systems, where it could be coupled with a gas turbine aero-engine. It could also be paired with batteries, fuel cells, or traditional jet engines to provide electric propulsion during certain flight phases.
Zoltan Spakovszky, the project leader, emphasizes the significance of megawatt-class motors for greening aviation, regardless of the energy carrier used. The design addresses challenges related to weight, size, and power generation efficiency.
The compact motor includes components like a high-speed rotor with an array of magnets, a low-loss stator with copper windings, an advanced heat exchanger, and custom-built power electronics. The team’s approach is an integrated design that optimizes various considerations, including thermal management, rotor dynamics, power electronics, and architecture, resulting in a compact and powerful solution.
The MIT team’s work will be presented at a session of the American Institute of Aeronautics and Astronautics – Electric Aircraft Technologies Symposium. Once fully assembled and tested, the motor could potentially power regional aircraft and be used in hybrid-electric propulsion systems. It’s also envisioned that multiple motors could be distributed along the wings of future aircraft configurations. The technology could eventually be scaled up for larger passenger planes.
The research addresses the urgent need to reduce carbon emissions in aviation and demonstrates the university’s commitment to interdisciplinary collaboration to tackle climate challenges.
Electric motor technology’s integration into the world of electric vehicles is unleashing transformative change. The journey from aircraft propulsion to energy efficiency improvements underscores the versatility and potential of these motors. As we navigate an evolving technological landscape, electric motors are proving to be the driving force behind a more sustainable and high-performing transportation future.
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