The new solution enables system developers to reduce development time for various development steps: from specifications analysis to hardware/software development and motor characteristic adjustments. This shortens, for example, the prototyped inverter system development period from two- to three years to just one year, thereby significantly contributing to the reduction of the development cycle and costs.

In an electrically powered system, the inverter plays a key role converting direct current (DC) power to alternating current and sends out optimum current to the motor whose rotation speed varies according to the driving conditions.

Renesas has been releasing inverters and solution kits with various capacity designs. In 2014, Renesas developed a solution that realized a size of 2.9 L in the 50 kW class. To respond to the growing needs for large-output motors for use in large vehicles, Renesas has expanded its lineup to support these large-output motors with its new 100kW class inverter solution included with a motor calibration tool.

Key features of the new 100 kW class inverter solution:

• Industry-leading volume and reduced inverter system weight enable mounting in even smaller spaces. The size and weight of the heat sink included in an inverter can be reduced by employing the temperature management technology that increases the responsiveness and precision of the temperature sensors integrated in the IGBT.

  In addition, the included MCU has an integrated enhanced motor control unit (EMU) function that enables motor control to be performed by a dedicated circuit instead of the CPU. This offloads the CPU to take on the CPU processing for the external automotive control unit (known as an electronic control unit, ECU), including the DC/DC converter, second motor, and cooling pump processing. This enables effective automotive ECU integration leading to improved use of the limited space in the engine compartment.

• Shortens development period by more than 50% with software that allows quick evaluation in actual cars. In addition to hardware, the inverter solution includes a motor calibration tool that maximizes the motor performance. This simplifies construction of motor control systems that are highly efficient at the system level. This allows system manufacturers immediately to evaluate a prototyped inverter system in an actual car.

• Higher fuel and electric power efficiency with devices optimized for HEV/EV applications. By using IGBT/FRD devices for reduced low conduction loss and low switching loss, the new inverter solution achieves a current loss reduction of approximately 12%, compared to existing Renesas products.

  By including Renesas main devices that are specialized for HEV and EVs, the new solution reduces the inverter’s power loss by approximately 10%. This enables increased motor efficiency, which ultimately contributes to increased fuel and electric power efficiency of the inverter system. The new solution is equipped with the RH850/C1H MCU Series, which has an industry-proven resolver-to-digital converter (RDC) function to convert the motor’s rotation angle from analog to digital. The RH850/C1H achieves high-precision motor control of up to 12 to 16 bits. The solution also includes the R2A25110 driver IC with micro-isolator technology enabling high-speed switching.

  Micro-isolators are circuits that combine signal transmission and isolation functions using transistors formed using the interconnect layers on the semiconductor chip.

Renesas will be introducing the 100 kW class inverter solution, including presenting demonstrations using the new solution, at Renesas DevCon Japan 2017.