Hardware-in-the-Loop Approach for Redundant Brushless Motor Control System

Brushless motors can be used in a very large range of industrial applications, including force feedback actuators in steer-by-wire systems. Due to the safety critical requirements of this kind of applications, a fault tolerant architecture is needed and it is implemented here using a hardware-in-the-loop (HIL) approach. To obtain a reliable control system a classic triple modular redundancy (TMR) architecture has been designed. The very same basic principles to control the motor have been implemented exploiting three different hardware platforms (8-bit, 16-bit and hybrid microcontrollers). All these three hardware modules execute the control algorithm and it will be the voter of the TMR architecture to determine the effective signals (PWM signals) needed to control the motor. This means that redundancy is not limited to the determination of the position of the drive shaft of the motor, but extended to the entire electronic control of the brushless motor