Electric Vehicles (EVs) are the future of mobility. With the rapid increase in awareness among public in greener vehicles and reducing carbon footprint coupled with government restrictions on the air pollutants and greenhouse gases, the EVs are a key to reducing CO2 emissions and maintaining a greener environment. The EV’s effective potential in real world driving conditions strongly depends on their performance and capability to maximize the efficiency of the powertrain in real life as well as during Type Approval (TA) testing procedures.

The NEDC (New European Driving Cycle) was the most widely used design cycle, primarily used to assess the emission level of the vehicles. Designed in the 1980s and adopted in 1990 and last updated in 1997, the NEDC aims to replicate how a car is typically being used in Europe. The inherent flaw in the NEDC is that it focused on a theoretical driving scheme and includes a number of tolerances and flexibilities not accurately reflecting the real-world driving conditions. This resulted in a totally unrealistic and impractical fuel consumption and engine emission readings, which are way off from reality. Average divergence of real-world from type approval CO2 emissions in Europe increased from roughly 9% in 2001 to about 42% in 2016.1

Attempting to close the gap between TA and real-world CO2 emissions, the European Commission introduced in September 2017, the Worldwide Harmonized Light Duty Test Procedure (WLTP, see Figure 1), replacing the previous procedure based on the New European Driving Cycle (NEDC). Since September 2018 onwards, WLTP came into full effect for all new car registrations. The WLTP relies on driving data collected from worldwide, under different driving conditions, making it as close to real world driving condition as possible. The WLTP emulates the stop, accelerate and brake conditions, across 4 distinct vehicle speed levels (see Table 1 for main situation comparisons). The testing also takes various temperatures, road types and gear shifts into account, making it a comprehensive way of measuring the aggregate fuel consumption rating and engine emission reading of the vehicle, before the vehicle actually hits the road.

The rigorous nature of the WLTP procedure is further illustrated by the EV Range assessment shown in Figure 2. For the same vehicle type, the vehicle range measured by the WLTP is dramatically lesser than that of NEDC. This is directly a consequence of the WLTP testing conditions which closely matches the reality.

Automakers and automotive system makers are facing new challenges to adapt to the more stringent fuel consumption and CO2 emission standards specified by the WLTP. The traditional automotive semiconductor providers have not caught up to these unique set of needs and are only offering generic solutions, primarily designed for internal combustion engines. In addition, these solutions face severe software processing bottlenecks as the software is not optimized for high efficiency. This results in overall reduction in efficiency and consequently a lower vehicle range. There is a strong need for a highly efficient solution, both at the hardware and the application software level.

Our OLEA® APP INVERTER HE application, our first addition to the OLEA® High Efficiency application software products portfolio, tackles these challenges directly, providing our customers a turnkey high efficiency Inverter/eMotor control. It includes the Adaptive PWM Control (APC) and FOC/SVPWM algorithms optimized for the OLEA® FPCU semiconductor. Simulations on a WLTP cycle demonstrate an energy gain of 20% under real-world driving conditions when compared to incumbent multi-core microcontroller-based applications. This directly results in the vehicle range boosted by up to 30% with the same battery capacity. Check out www.silicon-mobility.com for more details.

1 REAL-WORLD FUEL CONSUMPTION AND CO2 EMISSIONS OF NEW PASSENGER CARS IN EUROPE – ICCT Research
2 Figure source – WLTP Facts
3 Automobile Propre