Hyundai Motor India recently took the covers off its first electric vehicle (EV) – Kona Electric – considered a bold move in a country that does not quite have the adequate infrastructure to support EVs. The company launched its newest offering with an ARAI-certified driving range of 452 km, but developing the long range on this EV was a challenge that it had to deal with. Hyundai implemented a highly dense battery pack and a permanent magnet synchronous motor to deliver performance and efficiency. Auto Tech Review caught up with Yong Seok Kim, Ph.D (GLENN), Head of Team, Eco-Technology System Test & Development, Automotive Research & Development Division, Hyundai Motor Group, to understand the technology behind the new Kona Electric.
ENGINEERING & TECHNOLOGY
Hyundai’s engineers grappled with multiple challenges while developing the Kona Electric. The company spent around two to three years developing this vehicle, but it required additional time to make the vehicle ready for the Indian market. The Kona Electric features a liquid cooled battery system that has been integrated under the floor of the vehicle. And to optimise it for Indian conditions, Hyundai had to increase the vehicle’s clearance and subsequently carried out the same by changing certain chassis systems as well as working on the suspension.
Hyundai has tested the Kona Electric on an India-specific run cycle, which has enabled it to offer around 452 km of drive on a single charge. Kim believes the driving range in the real world would be impacted by the driver’s driving pattern, the vehicle’s condition and the traffic conditions. The Kona Electric is one of the most capable vehicles that can minimise the gap between the specification number and the real world driving range number, Kim noted. With multiple driving cycles at a global level such as MIDC, NEDC and WLTP, the Kona Electric’s range may vary depending on the cycle it has been tested under.
Hyundai has also worked on the energy density of the battery pack to enable the Kona Electric offer a long range. This EV features one of the highest battery pack densities seen in an electric vehicle. The energy density in the 39.2 kWh battery pack is nearly 256 W-h/kg, Kim apprised. Further, Hyundai has built its own thermal management system that optimises the operating temperature of the battery pack, offering ideal operating conditions. The Korean auto major has also performed multiple safety tests on the battery pack, including a spear penetration test to ascertain its safety. The Kona Electric is being retailed across global markets including Europe and the US and Hyundai has been able to conform to safety regulations across the globe.
Along with battery optimisation, Hyundai’s engineers worked on increasing the efficiency of the motor. The company has been able to achieve an efficiency of 89 % on the permanent magnet synchronous motor (PMSM) that has been used on the Kona Electric. The company made efforts to increase the entire system’s efficiency and changed the whole pulse-width modulation (PWM) strategy and the control algorithm.
Some body parts were also changed and durability of the motor itself was enhanced to offer a longer life. The optimisation of the vehicle’s dynamic performance was another challenge faced by Hyundai’s engineers. The company aimed to achieve performance without sacrificing on conventional virtues – cabin space, storage space, etc. Further, to increase dynamic performance the company’s engineers used a maximum torque algorithm on the electric motor and inverter control system.
Hyundai has also been working on developing its E-GMP (Electric Global Modular Platform) – a dedicated EV platform that will be used to develop more electric vehicles for its portfolio. Kim said styling and design engineers have more freedom at their disposal to design and develop the vehicle, while using a dedicated EV platform unlike gasoline-powered vehicles that have many design constraints. The E-GMP is said to offer flexible battery capacity for all segments, high voltage system to reduce charging time and a high power charger 400 kW that conforms to global standards. With a dedicated EV platform, engineers will be able to design different body styles while still leveraging the same platform and achieving optimal weight balance & load distribution.
Previous models of electric vehicles dominantly used the CHAdeMO charging standard. Hyundai has now moved away from CHAdeMO to the Combined Charging System (CCS) DC Combo type standard for charging its electric vehicles. Across US, Europe and most countries, the CCS DC Combo type 1 & type 2 standards are being utilised. Kim said Hyundai has both technologies ready and can supply these as per different market requirements.
Further, the Korean carmaker also has the technology to supply Chinese GB/T charging standards. In India, Hyundai has tied up with Indian Oil Corporation Ltd to set up four DC fast charging stations across four Tier I cities in India to mitigate any range anxiety among potential buyers.
TEXT: Joshua David Luther