Periodic Reporting for period 1 - SCAPE (Switching-Cell-Array-based Power Electronics conversion for future electric vehicles)
Période du rapport: 2022-07-01 au 2023-12-31
SCAPE aims at achieving three main objectives: i) propose a standardisable modular and scalable approach, based on multilevel technology, for the design of the EV power conversion systems ii) develop highly-compact and integrated building-block implementation. iii) propose intelligent modulation and control strategies, online diagnosis, and digital twin for predictive maintenance with machine learning. Reaching these objectives will enable reducing the cost of the EV power electronics thanks to scale economies, improving its performance features (reliability, efficiency, power density, etc.), and enabling advanced functionalities.
SCAPE's pathways towards impact focus on satisfying the user’s needs, increase the acceptance and affordability of zero-emission vehicles, reduce green-house gasses emission, and enable a full-market penetration of the EV. Having this approach adopted by EU automotive manufacturers will allow creating a cost-efficient production chain in the EU based on economies of scale and advanced integration technologies, as a competitive advantage against other manufacturers.
In the first reporting period (M1-M18, RP1), SCAPE has successfully conceptualized a modular and scalable design approach for the EV powertrain based on a basic building block; i.e. the switching cell (SC), and on multilevel converter topologies, able to increase the powertrain performance and reduce its cost. The design approach has been defined for three relevant use cases (motorbike, passenger car, and truck), defining the relevant requirements for the devised technologies and prototypes development. Novel powertrain architectures have been defined that allow integrating the functionalities of traction inverter and on-board charger (OBC) into a single power converter (the integrated inverter on-board charger, IIOBC), allowing for further power-density increase, cost reduction, and enhanced fault tolerance. An online monitoring system (OMS) and a powertrain digital twin (DT) have been conceptualized and designed to an extent, aimed to perform prognosis and health management (PHM) functions. Steps towards the manufacturing of the first batch of SCs implemented with chip-embedding (CE) technology have been achieved. Delivery of the first SCs batch is expected on M22.
Extensive multiphysics simulations of the CE SC designs have demonstrated the achievement of parasitic inductance and thermal resistance reduction KPIs in excess. Moreover, simulations of the proposed IIOBC have also shown the achievement of the efficiency, power density, and switching frequency KPIs. Additionally, experimental tests have been performed with mock-up versions of the SC and converter leg (CL), which have served to validate basic and advanced functionalities, as well as the proposed hierarchical converter control architecture.
SCAPE has also proposed advanced converter topologies integrating the functionalities of traction inverter and OBC, allowing all types of charging (dc, single-phase ac, three-phase ac), and modular, scalable, fault-tolerant, highly-compact, and cost-competitive powertrains.
SCAPE has defined two designs for the switching cell (SC), the basic building block to conceive the modular and scalable power converter topologies. These designs consist of a low-voltage SC (LVSC) and a high-voltage SC (HVSC). These two SCs allow fully meeting the voltage and power ranges in the powertrain power converters for the considered use cases, as well as the for the converter prototypes under development.
The required manufacturing steps for the chip-embedded (CE) SC were defined, and an optimized design for CE SC boards has been completed and validated through electromagnetic, thermal, and thermo-mechanical finite-element simulations. Partners also developed the individual CE SC cooling system, based on aluminium heatsinks and 3D printed plastic housings for liquid cooling.
Through ruggedness tests on the SC candidate power devices, electro-thermal variables were detected, indicative of premature-failure and aging. These results served to define the variables to be monitored by the OMS.
Preliminary results show an efficiency of the converter in traction mode superior to the objective KPI, meeting also the power density KPI. Multiphysics simulations performed on the CE SC designs have demonstrated a great reduction on the SC parasitic inductance and thermal resistance compared to conventional approaches for the converter implementation, meeting in excess the project KPIs. Further validation of these results will be performed with the CE SC and CL prototypes, as well as the final converter prototypes during RP2 and RP3.