EVreporter Visits C1973 EV Powertrain Lab at IIT Bombay

IIT Bombay recently organised e-Mobility Tech Day at their campus, facilitating interactions between industry, academia, and policymakers. In his address, Mr Gajanan Gandhe (Country Head, DANA India) noted that e-Mobility provides ample opportunities for R&D and manufacturing in the areas of powertrain (Motors and controllers), battery technology, die-casting parts, rare earth magnets, wiring harness & cables, encoders & sensors, testing & validation equipment and automation equipment. Dr Sandeep Anand, Professor In-Charge, C1973 EV Powertrain Lab, shares that the market for domestic motors, inverters, and chargers only for the e-2W segment is expected to be more than INR 20,000 crores.

Recognising the need for leapfrog R&D in these strategic areas, the institute has established this dedicated Lab focussed on EV powertrains for small vehicles.

Established in Feb 2024, through a generous contribution from IIT Bombay 1973 batch, the lab aims to be the preferred source of R&D for automotive firms in India. The lab focuses on India-specific powertrain requirements, including robust & low maintenance, high temperature and overloading.

In terms of immediate projects, the researchers are undertaking one key project in each thematic area of the lab:

• Inverters/Motor Controllers: To meet the space and efficiency requirement of light EVs, the lab is exploring the use of wide band-gap power devices and integration into vehicle power electronics.

• Motors: To reduce dependence on imported NdFeB (rare earth magnets), the lab is researching SRM and SynRM motor topologies, targeting similar power densities and efficiencies as popular motor technologies.

• Battery Systems/BMS: Efforts are underway to increase battery packs’ cycle life and safety through battery characterisation and modeling.

Focus on GaN Motor Controllers

Innovation in power electronics is the key to unlocking the full potential of electric vehicles. Prof Sandeep gave us an insight into current work at IIT Bombay’s EV Lab, sharing about their work on GaN (Gallium Nitride) motor controller technology targeted for electric 2Ws and 3Ws.

Notably, GaN semiconductors offer superior switching performance and efficiency compared to traditional silicon-based IGBT devices.

To leverage the unique properties of GaN to create a highly efficient and compact motor controller, the lab is addressing key technical challenges such as high dV/dt (rate of voltage change), which can lead to electromagnetic interference (EMI), and ensuring precise gate drive control for optimal performance.

To tackle thermal management in such a compact form factor, the lab’s researchers have identified an optimal design balance between the use of parallel devices and the overall controller size, ensuring efficient heat dissipation without compromising performance.

“In the future, we foresee GaN technology being adopted across the entire EV spectrum, from personal electric scooters to larger commercial vehicles. With GaN technology, these vehicles can be made more compact and customized to fit various applications and designs. Our work at IIT Bombay is a step forward in realizing this vision, setting new benchmarks for efficiency, performance, and reliability in electric mobility”, adds Prof Sandeep.

Equipment and Lab Facilities

The lab is well-equipped for the designing, prototyping and testing EV Powertrain components, including motors, inverters, controllers and BMS. The facility has 5 dedicated areas:

• Vehicle Fitting Area

• Motor Fabrication

• Motor & Inverter Test Bench

• Inverters, Charges and BMS

• Battery Modeling and Characterization

The equipment for motor design and prototyping includes Wire Cut EDM, CNC Milling, FEA software, etc., while the battery characterisation facility includes a temperature chamber, battery recycler, and potentiostat. The lab is well equipped with AC and DC sources up to 800V DC and 400V AC and advanced electrical and thermal measurement instruments: high-bandwidth oscilloscopes, differential probes, current probes, thermal imagers, dataloggers, etc.

Many PhD students in the lab are working closely with the leading automotive suppliers to solve the current technology challenges with today’s electric vehicles. True to the industry and country’s current needs, the lab aims to create 10-15 key technology solutions/patents over the next 5 years while providing experimental facilities for engineering students and PhD researchers.

Domestic technology development is essential to India’s strategy for self-reliance in the automotive space. At EVreporter, we look forward to covering technology innovations from this lab in our subsequent issues.

Also read: Mushashi Seimitsu partners with Log9 for EV powertrain solutions