SaberRD Design Example: Functional Safety Analysis for a Motor Drive Design

Vishwa

Introduction:

This design example describes a torque-controlled motor drive which will be used for Functional Safety investigations. The permanent magnet synchronous motor is powered by a bridge with ideal switches and diodes. The control-signals for the bridge are generated by the FOC-block (field oriented control), that uses motor-angle and motor-current information as input signals. A battery supplies the system. The motor drive is protected by a fuse. Additionally, a Torque Monitor can be activated that uses the information from a torque-sensor.

By using SaberRD’s Fault Analysis, various hardware and software faults will be injected in the motor drive system. The resulting fault-effects will be analyzed and tested if they violate safety criteria. In case of violation of safety criteria, a mechanism will be developed to detect injected faults and to bring back the system into a safe state. In addition, the Distributed Iterative Analysis feature is demonstrated to increase productivity by reducing the simulation time by paralleling the simulation runs.

Circuit Snapshot:
Refer to the attached snapshot "motor_drive_FS.png".

How To Use:

1. Download the attached design folder "motor_drive_FS.zip".
2. Extract the files to any location on your PC.
3. Invoke SaberRD 2016.03.
4. Open the design "motor_drive_FS.ai_dsn".
5. Run the Experiment “Nominal_Behavior” as explained in page 1 of Readme.pdf file to understand the behavior of the design.
6. For Functional Safety investigations, two other Experiments are available which execute a fault-analysis and automatically verify simulation results (“Fault_Analysis_with_Fuse” and “Fault_Analysis_with_Fuse_and_Torque_Monitor”).
   

For more description about the design, Experiments and results, refer to Readme.pdf file available in the attachment.

Note:
This design works in SaberRD 2016.03 commercial version, and not in the student version.