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Energy efficient motors are gaining acceptance in India to confront with the global efficiency standards. This increasing awareness towards energy conservation combined with growing industrial infrastructure are driving the growth of the electric motors industry. Moreover, essential government initiatives such as 100 per cent electrification of vehicles might be the push needed to complement the growth of electric motors market over the coming years, says Neellohit Banerjee.
Rising awareness towards energy conservation along with growing industrial infrastructure are the factors which are majorly steering the growth of electric motors market in India. Energy efficient motors consume lesser power than the traditional ones and as a result, there is a widespread adoption of these motors in India's electric motors market. Additionally, motor manufacturers are continuously coming-up with advanced motor technologies to satisfy consumer demand. Moreover, certain key government initiatives such as 100 per cent electrification of vehicles can boost the growth of electric motors over the coming years. On the other hand, the Indian electric drives market is projected to grow at a CAGR of over 7 per cent up to a period of 2023. AC drives captured majority of the market share and would dominate the market over the coming years.
When it comes to developing new motor technologies, copper continues to remain a significant component when it comes to improvements in motor efficiency. The standard induction motor has become more and more efficient through more copper in the windings, a higher-grade steel core, improved bearings and insulation, and better cooling fan design. As the search for ever increasing efficiency brings the advent of new motor technologies and designs beyond the induction motor, copper will continue to be integral to the efficiency and longevity of these new technologies: from switched reluctance motors, permanent magnet motors and copper motor rotors.
Long used in servo motor applications, Permanent Magnet Synchronous Motors (PM) are gaining increased use in industrial motor driven systems. The PM motor technology replaces the aluminum bars in the rotor with powerful permanent magnets created using rare earth elements; these are either surface mounted (SPM) or internally mounted (IPM). The basic stator in a permanent magnet motor has resemblance to a traditional copper wound induction motor; only the rotor in these motors stands out, using permanent magnets either stuck to the surface of the rotor or bar magnets embedded in the rotor laminations. Some of the advantages that these motors provide are excellent torque-speed curve, dynamic response, high efficiency and reliability, low maintenance, longer lifetime etc.
A switched reluctance motor (SRM) is a brushless DC electric motor that provides continuous torque. The SRM electronic drive is paired to the motor and together, they form a closely matched system. The SRM is a viable replacement and improvement to induction motors in variable speed applications. The switched reluctance technology has been present from a very long time but what the reason for which this technology has come to the forefront of today's advanced motors is the advent of power electronics and computing capability that allows commercially viable implementation. The quantity and type of copper wire are key to the design of an SRM. Each turn of the coil nests together to help fill the large stator slot allowed by the SRM design. Copper is an essential component to the coils. Generally 100% copper is used to wind electric motors because it has much lower electrical resistance than alternative materials such as aluminum. Low winding resistance leads to less wastage of heat. This, in turn, improves energy efficiency and advantageously reduces the motors’ operating temperature.
The innovation of the copper rotor motor (CRM) technology had risen since it was required to meet the low voltage motor market demands for greater energy efficiency; a demand not met by the traditional die cast aluminum rotor design. The goal was to gain efficiency using new copper rotor technology but retain the same footprint as the traditional aluminium rotor design. The significant investment in design and development of the CRM was justified by the efficiency gains over the conventional aluminium rotor designs. The initial purchase price of a copper rotor motor is slightly higher than the aluminum rotor motor making the payback justification a factor. However, payback is relatively short and generally not an issue given the typical 20 year design life of the motor.
Each of these motor technologies, depend on copper in one way or the other, in terms of their design to produce motors that are more efficient and more reliable. The PM motor with powerful permanent magnets in its rotor, the SRM with power electronic switching and its copper dense stator and rotor, and the CRM with the current-resistance-reducing cool running rotor, all provide options to accomplish energy reduction objectives and improve performance.
One extremely crucial segment which will see the use of electric motors is electric vehicles. At Bosch, the engineers are trying to turn Maruti Suzuki Baleno into an electric vehicle. “The electric motors will be a part of the vehicle, and currently with electric motors, we are be able to achieve a speed of 100 km per hour. If everything goes well, we can see it getting launched at the end of 2020 or the starting of 2021,” informs Vivek Tak, Senior Engineer, Robert Bosch. India is facing electricity problems currently and all the big OEMs, namely Mahindra, Tata etc. have the capability to provide electric cars, but since BS VI will be coming in 2020, the market is in chaos right now. Hence OEMs are stalling their plans for the EVs since their prices are high. When BS VI comes out, the prices will go up. “So right now no car company will launch these products because these are costly,” Tak adds.
“Also, we are not equipped with the power which we want to deliver through electric motors right now. We are near to it but we haven’t reached the optimum level. We need one or two years for that, for which R&D is going on,” Tak explains.
Automation and Industry 4.0 and automation play a major role in manufacturing. According to Tak, “The product costing has reduced a bit because of automation and delivery is also marginally better. Machines are now more equipped with faster delivery and fast processing, and also intelligence due to AI. We have a separate department in Bosch now for machine learning and artificial intelligence, and another department for IoT. We are putting sensors in our machine, and if anything is going wrong with the machine parts, automatically we will get to know about that and we can repair it before it can shut down. So with the some investment, we are able to achieve some high efficiency. In our core processing areas, we are equipped with the latest Industry 4.0 terms.”
Another interesting aspect where electric motors find their usage is a drone. The motors which are used predominantly are brushless DC (BLDC) motors. It is called an outrunner, since the outer cell of the motor rotates, not the inner one. Drones which are between 0-250gm fall in the micro category and can fly upto an altitude of 200m. The government has ruled that drones falling in this category do not require a licence to be operated. Hence electric motors manufacturer are trying to produce lightweight motors. “Yes. Recently there has been a trend in BLDC manufacturers such as T Motors and Turn Igy,” says Pankaj Sharma, Robotics Engineer, Drishti Works. “If we see how BLDC actually works, we use permanent magnets inside it. Previously those magnets had a size of approximately one inch, but currently manufacturers have understood that magnets of one inch are not good enough. So they opted for using 1/10 of the multiple permanent magnet,” he explains.
Earlier, for small motors, there wasn’t such high current demand. Since the drones are very agile, fast and reactive, a high burst of current needs to be delivered into the motor and the motor should be able to tolerate that. Hence people have moved to something unconventional, which is, a thicker wire. Some people have started using windings of silver wire instead of copper wire, just to increase efficiency. When asked how Industry 4.0 has changed the face of motors manufacturing, Sharma replies, “The only thing which has improved with the Industry 4.0 trend right now is the precision in the machining of the motors. It has improved magnificently, and if you take the same motor of any company and compare them with the current ones, the weight will differ by 1 or 2g. Earlier it didn’t matter, but now in the drone industry, each and every gram matters for flying a drone. Currently, the weight is pretty much accurate.”
When asked about the challenges of the motors industry, Sharma says, “The problem currently is that everyone wants to have a customised product. Talking from the drone perspective, if I want to design a drone, most of the times we are totally dependent on the combination of motors available, and that hampers your design. That is something which is changing but it’s a big challenge. There is no proper standardisation of electric motors as such. So we depend on the Kv rating and the life expectancy of the motors.”
According to 6Wresearch, India’s Electric Motors market is projected to grow at a CAGR of 6.1 upto 2023. AC motors segment held major revenue share and is expected to maintain its dominance during the forecast period as well. In terms of power capacity, fractional horsepower (FHP) motors captured majority revenue share in 2016, however on account of growing industrial sector, integral horsepower (IHP) motors are projected to exhibit highest growth over the coming years.
In terms of region, the western region contributed highest revenue share towards electric motors market in India mainly factored by Maharashtra and Gujarat. Further, the industrial segment emerged as the largest end-user of electric motors. Further, in the industrial segment, electric motors consume over 30 per cent of the overall power requirement. However, the transportation segment is expected to exhibit highest growth over the coming years.
India electric motors market has seen stable rise on a YoY basis. Elements such as strict power consumption standards and adoption of energy saving measures have led to increased production and expansion of electric motors market. Additionally, rapid urbanisation and developing real estate sector are resulting in growing HVAC industry which has further propelled the demand for electric motors in India. Furthermore, as a result of growing consumer demand for energy saving capabilities in electric motors, manufacturers are looking for new ways to innovate. Energy efficient motors are gaining acceptance in India to confront with the global efficiency standards.
This increasing awareness towards energy conservation combined with growing industrial infrastructure are driving the growth of the electric motors industry. Energy efficient motors are less power consuming than the traditional ones and as a result they are gaining popularity in adoption in India's electric motors market. Motor manufacturers are continuously coming up with advanced motor technologies to tackle the diverse needs of the consumers. Moreover, essential government initiatives such as 100 per cent electrification of vehicles might be the push needed to complement the growth of electric motors market over the coming years.
The product costing has reduced a bit because of automation and delivery is also marginally better. Machines are now more equipped with faster delivery and fast processing, and also intelligence due to AI.
Vivek Tak, Senior Engineer, Robert Bosch
Energy Efficient Motors
Permanent Magnet Synchronous Motors
DC Electric Motor
Cool Running Rotor
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