Advanced integration for EV E-Axles

Developed in collaboration with Nidec Corporation, this PoC integrates a motor, a gear (reduction gear), an inverter, a DC/DC converter, and an on-board battery charger (OBC). System-level testing was also completed to ensure its performance. Renesas will showcase a live demonstration of the new E-Axle design at electronica 2024 in Munich, Germany, November 12-15 (Hall B4, Stand 179).  

The E-Axle is a unit in EVs that combines a drive motor, a gear, and an inverter. By integrating multiple functions, the E-Axle system can reduce system size and weight, simplifying EV design. Renesas provided key components, including semiconductors and a reference design for the new 8-in-1 E-Axle system. Renesas also plans to deliver turnkey semiconductor solutions for various X-in-1 systems based on the reference design verified through this PoC. Armed with these solutions, developers can implement and evaluate X-in-1 systems instantly, accelerating EV development.

Together with the motor and gear from Nidec, the eight functions in this PoC include an inverter from Renesas with 70~100kW output performance with the maximum efficiency of 99 percent or higher; a 1.5kW output DC/DC converter, a 6.6kW charge OBC; a power distribution unit (PDU); a battery management system (BMS); and Positive Temperature Co-efficiency (PTC) heater control for cars. While generally each function of an E-Axle requires a dedicated MCU and a power management IC (PMIC) to control an X-in-1 system, Renesas successfully implemented a new E-Axle system which can operate with only one MCU and a PMIC to control the entire 8-in-1 system. By systematically integrating these functions with a single MCU, the PoC has significantly reduced the number of components, cost and size.

This PoC, tested for optimal performance, includes numerous Renesas products: the 32-bit MCU RH850/U2B for automotive control, a PMIC for the MCU, the RAJ2930004AGM isolated gate driver, an IGBT module for the inverter, power devices for the DC/DC converter and OBC. Leveraging these innovations, Renesas can provide comprehensive system support and software for customers, along with key devices for X-in-1 solutions. Renesas is committed to providing comprehensive system solutions including reference designs and software to accelerate EV development.  

“We are thrilled to deliver the world-class 8-in-1 E-Axle solution and have successfully verified its operational performance in collaboration with Nidec,” said Chris Allexandre, Senior Vice President and General Manager of Power at Renesas. “We are committed to delivering a broad range of power management products that work together with our digital products to provide complete, ready-to-use, system-level solutions. This approach enables Renesas to help customers accelerate their development and time to market.”  

“In the rapidly changing EV market, there is a growing need for smaller and lower-cost E-Axle systems,” said Ryuji Omura, Senior Vice President, Deputy Chief Technology Officer and Head of Nidec Semiconductor Solutions Centre at Nidec. “Having a single ECU manage an electric powertrain control unit will help lower the weight and cost of the system, reducing the number of components. We were able to develop the world's first PoC that controls an 8-in-1 system with a single MCU, and we are grateful for the Renesas team’s passion and collaboration on this project. This project made us realize the importance of developing a scalable design methodology, as the levels of X-in-1 system integration vary from segment to segment. By modifying the software configuration for multi-core MCUs, we expect to build the foundation for an X-in-1 platform that can flexibly accommodate various combinations.”