SAIC Motor Uses Simulink to Develop Embedded Control System for the Roewe 750 Hybrid Sedan

MathWorks today announced that SAIC Motor Corporation developed the hybrid control unit (HCU) for the Roewe 750 hybrid sedan by using Model-Based Design with Simulink, Stateflow, and Embedded Coder. This design approach enabled SAIC Motors to model, simulate, verify, and automatically generate production code for the HCU, completing its development in-house in 25% less time than originally estimated.

By applying Model-Based Design with Simulink and Stateflow, SAIC Motor engineers were able to model and refine the control algorithms for the HCU by running multiple simulations to evaluate different powertrain system configurations and compare each configuration’s effect on fuel economy and drivability. Because the vehicle and several key components, including the battery and motor, were being developed concurrently, this approach also eliminated the misunderstandings that typically arise from interpreting written specification documents. In addition, Embedded Coder automatically generated 98% of the production code, helping to minimize hand-coding errors and allowing for fast updates of multiple modules. The team developed a systematic verification process that used Simulink Verification and Validation to enforce modeling standards. This process enabled them to find and fix errors earlier in the design process, which reduced reliance on in-car testing, saved time, and cut project costs.

“Three years ago, SAIC Motor did not have rich experience developing embedded control software. With some team members new to embedded development, we needed an industry-proven approach,” said Jun Zhu, general manager of Shanghai E-propulsion Auto Technology Co., the SAIC Motor subsidiary that develops electric and hybrid propulsion technologies. “We chose Model-Based Design because it is a proven and efficient development method. This approach helped us develop the highly complex HCU control logic and complete the project ahead of schedule.”

“SAIC Motor’s HCU development project is a great example of how Model-Based Design has enabled automotive companies in emerging markets to develop core IP,” said Jon Friedman, automotive industry marketing manager at MathWorks. “Model-Based Design works as a common platform for different groups, offering a single development environment from requirements through implementation and verification.”

The complex control logic in the Roewe 750 Hybrid Sedan HCU, which coordinates the electric motor and engine, has been vital to SAIC Motors in achieving its goal of improving fuel economy and emissions over the nonhybrid version. With this success, the SAIC Motor team is now using Model-Based Design on new energy vehicle programs, including the Roewe 550 strong hybrid and an electric vehicle.

More details on SAIC Motor’s use of MATLAB and Simulink can be found in the user story “SAIC Motor Develops Embedded Control System for the Roewe 750 Hybrid Sedan.”