Periodic Reporting for period 2 - SCAPE (Switching-Cell-Array-based Power Electronics conversion for future electric vehicles)
Période du rapport: 2024-01-01 au 2025-06-30
In power electronics, the traditional design approach of power converters involves a range of power semiconductor devices with different ratings, optimized to operate at different conditions, where different suitable ancillary circuitry and power circuit topologies are also required. This dispersion in power devices and circuits leads to significant engineering efforts, the inability to take full advantage from scale economies to reduce costs, and the inability to concentrate efforts to improve performance. In the electric vehicle (EV) market, this is translated to a lack of standardization on the EV power conversion system designs across the different models and types of vehicles available, meaning that nowadays EV OEMs invest billions of euros to develop their own solutions.
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.
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 second reporting period (M19–M36, RP2), SCAPE progressed decisively toward its technical goals.
Core work focused on defining modular, scalable powertrain converters and controls using neutral-point-clamped (NPC) multilevel topologies across a wide EV voltage/power range. The architecture is stratified into switching cell (SC) hardware with primary control, converter-leg (CL) hardware with secondary control, and converter-level hardware with tertiary control, with coordinated advances at all three layers.
At SC level, low-voltage (LVSC) and high-voltage (HVSC) designs were refined and validated. The LVSC targets the battery interfacing converter (BIC), the HVSC the integrated inverter charger (IIC). Multiple HVSC iterations improved circuit behavior and verified functionalities. A first chip-embedded (CE) HVSC batch was fabricated and tested, demonstrating robustness and performance gains versus conventional assemblies using power devices with discrete packages. LVSC iterations cut power-loop inductance and improved thermal performance, enabling higher power density and cost reduction. New gate-driver concepts allowed precise current sharing in parallel devices, a prerequisite for highly granular SC arrays and modular CL designs.
At CL level, partners executed computer-aided optimizations to select IIC and BIC leg configurations for the final prototypes, balancing performance and complexity. Baseline secondary control interfaces were fixed, defining signals exchanged with primary and tertiary layers. Available degrees of freedom were identified and reserved to support prognostics and health management (PHM).
At converter level, development centered on two units: the IIC and the BIC. The selected IIC topology, combined with an open-ended-winding machine, enables traction plus single- and three-phase charging within a single converter–machine pack; i.e. a 3-in-1 assembly. The BIC’s multiport architecture supplies multiple auxiliary buses (e.g. 12/24/36 V) from a traction module (≈400 V), better matching loads such as autonomous-driving-related electronics and thermal systems. Modulation and control were implemented to realize these modes, while control freedom was mapped for PHM use. The under-development prototypes (passenger-car use case) are configured with 3-level NPC hardware: IIC at 800 V, 100 kW; BIC at 400 V to 12/24 V, 1 kW. A first-generation discrete “mock-up” IIC prototype validated SC/CL hardware choices and baseline secondary and primary control.
Advanced modulation and PHM algorithms were engineered to raise efficiency, reliability, and lifetime. Ruggedness and aging analyses of SCs under diverse operating conditions guided design margins. A unified online monitoring system (OMS) and digital twins for converter, machine, and battery were developed to estimate state-of-health (SoH) with minimal sensing. The OMS and digital twins feed PHM actions that rebalance SC temperatures, derate or bypass stressed cells, enhance fault tolerance, and issue predictive maintenance warnings. Converter digital twins and health-management strategies were validated in simulation, demonstrating the potential to extend component lifetime and improve overall powertrain efficiency and reliability.
Core work focused on defining modular, scalable powertrain converters and controls using neutral-point-clamped (NPC) multilevel topologies across a wide EV voltage/power range. The architecture is stratified into switching cell (SC) hardware with primary control, converter-leg (CL) hardware with secondary control, and converter-level hardware with tertiary control, with coordinated advances at all three layers.
At SC level, low-voltage (LVSC) and high-voltage (HVSC) designs were refined and validated. The LVSC targets the battery interfacing converter (BIC), the HVSC the integrated inverter charger (IIC). Multiple HVSC iterations improved circuit behavior and verified functionalities. A first chip-embedded (CE) HVSC batch was fabricated and tested, demonstrating robustness and performance gains versus conventional assemblies using power devices with discrete packages. LVSC iterations cut power-loop inductance and improved thermal performance, enabling higher power density and cost reduction. New gate-driver concepts allowed precise current sharing in parallel devices, a prerequisite for highly granular SC arrays and modular CL designs.
At CL level, partners executed computer-aided optimizations to select IIC and BIC leg configurations for the final prototypes, balancing performance and complexity. Baseline secondary control interfaces were fixed, defining signals exchanged with primary and tertiary layers. Available degrees of freedom were identified and reserved to support prognostics and health management (PHM).
At converter level, development centered on two units: the IIC and the BIC. The selected IIC topology, combined with an open-ended-winding machine, enables traction plus single- and three-phase charging within a single converter–machine pack; i.e. a 3-in-1 assembly. The BIC’s multiport architecture supplies multiple auxiliary buses (e.g. 12/24/36 V) from a traction module (≈400 V), better matching loads such as autonomous-driving-related electronics and thermal systems. Modulation and control were implemented to realize these modes, while control freedom was mapped for PHM use. The under-development prototypes (passenger-car use case) are configured with 3-level NPC hardware: IIC at 800 V, 100 kW; BIC at 400 V to 12/24 V, 1 kW. A first-generation discrete “mock-up” IIC prototype validated SC/CL hardware choices and baseline secondary and primary control.
Advanced modulation and PHM algorithms were engineered to raise efficiency, reliability, and lifetime. Ruggedness and aging analyses of SCs under diverse operating conditions guided design margins. A unified online monitoring system (OMS) and digital twins for converter, machine, and battery were developed to estimate state-of-health (SoH) with minimal sensing. The OMS and digital twins feed PHM actions that rebalance SC temperatures, derate or bypass stressed cells, enhance fault tolerance, and issue predictive maintenance warnings. Converter digital twins and health-management strategies were validated in simulation, demonstrating the potential to extend component lifetime and improve overall powertrain efficiency and reliability.
In RP2, SCAPE project has been able to demonstrate part of its target KPIs, namely:
- Conversion efficiency: Achieved 97.8%, surpassing the target of 97.5%. That is a 44.2% reduction of losses compared to reference commercial metrics. Demonstrated in simulation.
- IIC converter power density: Achieved the ambitious target of 100 kW/litre, marking a significant improvement over the reference commercial product (20 kW/litre). Demonstrated through simulation results.
- Volume gain: Up to 10 liters, thanks to the inverter and on-board charger integration. Demonstrated through simulation results.
- Thermal resistance from semiconductor junction to switching-cell backside: Achieved 0.5 K/W, surpassing the targeted 0.855 K/W and representing a significant improvement over commercial benchmarks (1.14 K/W). Demonstrated through experimental results with the 1st generation HVSCs.
- Switching-power-loop parasitic inductance: Reduced to 2 nH, exceeding the target of 12 nH and considerably lower than the commercial reference of 20 nH. Demonstrated through experimental results with the 1st generation HVSCs.
- Switching frequency: Increased to 50 kHz, from the typical 10-20 kHz of commercial options. Demonstrated through simulation results.
These results entail the following potential impacts. The attainment of these impacts is highly dependent on the uptake of SCAPE technology by the EV industry, which can be boosted by future developments on high-TRL demonstrators and comprehensive commercialization assessments.
Scientific:
- Cost reduction of at least 40% for the EV power converters.
- Improved efficiency with loss reduction of 35%.
- Improvement on power converters thermal performance.
- Increase in the EV driving range.
- Improvement of the powertrain reliability.
Environmental:
- Reduction of greenhouse effect gases (GHG).
Societal:
- Accelerate uptake of zero-emission affordable mobility.
- Smart, sustainable, and user-centric mobility.
Economic and industrial:
- European industrial leadership from EV production reduction cost.
- Reduction of the manufacturing steps and materials required to produce power converters.
- Conversion efficiency: Achieved 97.8%, surpassing the target of 97.5%. That is a 44.2% reduction of losses compared to reference commercial metrics. Demonstrated in simulation.
- IIC converter power density: Achieved the ambitious target of 100 kW/litre, marking a significant improvement over the reference commercial product (20 kW/litre). Demonstrated through simulation results.
- Volume gain: Up to 10 liters, thanks to the inverter and on-board charger integration. Demonstrated through simulation results.
- Thermal resistance from semiconductor junction to switching-cell backside: Achieved 0.5 K/W, surpassing the targeted 0.855 K/W and representing a significant improvement over commercial benchmarks (1.14 K/W). Demonstrated through experimental results with the 1st generation HVSCs.
- Switching-power-loop parasitic inductance: Reduced to 2 nH, exceeding the target of 12 nH and considerably lower than the commercial reference of 20 nH. Demonstrated through experimental results with the 1st generation HVSCs.
- Switching frequency: Increased to 50 kHz, from the typical 10-20 kHz of commercial options. Demonstrated through simulation results.
These results entail the following potential impacts. The attainment of these impacts is highly dependent on the uptake of SCAPE technology by the EV industry, which can be boosted by future developments on high-TRL demonstrators and comprehensive commercialization assessments.
Scientific:
- Cost reduction of at least 40% for the EV power converters.
- Improved efficiency with loss reduction of 35%.
- Improvement on power converters thermal performance.
- Increase in the EV driving range.
- Improvement of the powertrain reliability.
Environmental:
- Reduction of greenhouse effect gases (GHG).
Societal:
- Accelerate uptake of zero-emission affordable mobility.
- Smart, sustainable, and user-centric mobility.
Economic and industrial:
- European industrial leadership from EV production reduction cost.
- Reduction of the manufacturing steps and materials required to produce power converters.