Motor Control Algorithms

The field of motor control has undergone rapid expansion due mainly to the advantages of semiconductors in both power and signal electronics and the processing capability of micro-electronic microprocessors and DSPs. These technological improvements have enabled the development of really effective drive control with ever lower power dissipation hardware and ever more accurate control structures. The electrical drive controls has become more accurate in the sense that not only are the DC current and voltage controlled but also the three phase currents and voltages are managed by combined use of MCU and software algorithms.

Suggested Renesas MCUs
  Control Methods MCU Requirements Suggested MCUs
RL78
Family
RX
Family
RH850
Family
RZ/T1
Group
Universal / DC Motor Control TRIAC Control GPIO, Timers, Interrupts, A/D Channels      
PWM Chopper Control PWM Channel, Timers, A/D Channels      
BLDC Motor Control Trapezoidal Drive Control Input Capture, Interrupt, PWM Timer for Three-Phase motor control      
Sinusoidal Drive Control Input Capture, Interrupt, PWM Timer for Three-Phase motor control    
Simplified Vector Control Input Capture, Interrupt, PWM Timer with Deadtime for Three-Phase motor control  
Vector Control(FOC) High Performance MCU+MAC、High-Speed A/D Converter, Input Capture, Interrupt, PWM Timer with Deadtime for Three-Phase motor control  
Sensorless Trapezoidal Drive Control Input Capture, High-Speed A/D Converter, Interrupt,
PWM Timer for Three-Phase motor control
     
Sensorless Vector Control High Performance MCU+MAC、 High-Speed A/D Converter, Interrupt, PWM Timer with Deadtime for Three-Phase motor control  
AC Motor Control V/F Control Input Capture, Interrupt, PWM Timer for Three-Phase motor control      
Simplified Vector Control Input Capture, Interrupt, PWM Timer with Deadtime for Three-Phase motor control  
Vector Control(FOC) High Performance MCU + MAC, High-Speed A/D Converter, Input Capture, Interrupt, PWM Timer with Deadtime for Three-Phase motor control  
Sensorless Vector Control High Performance MCU + MAC, High-Speed A/D Converter, Interrupt, PWM Timer with Deadtime for Three-Phase motor control  
Comparison of Different Motor Control Algorithms

The table below capture the salient characteristics of the most prevalent motor control algorithms

Motor Control Algorithm Comparison

Control Algorithm Motor Type Torque Controllability Feedback Sensors MCU Processing Requirements
TRIAC Control Universal / DC No Torque Control Not Required Not Required
PWM Chopper Control Universal / DC No Torque Control Not Required 8bit
V/F Control AC Poor Dynamic Torque Control Not Required 8-16bit
Trapezoidal Drive Control BLDC High-Harmonic Loss, High-Torque Ripple Hall Sensor 8-16bit
Sinusoidal Drive Control BLDC, AC Low-Harmonic Loss, Low-Torque Ripple Hall Sensor, Encoder 16-32bit
Simplified Vector Control BLDC, AC Low-Harmonic Loss, Low-Torque Ripple Hall Sensor, Encoder 16-32bit
Vector Control BLDC, AC Low-Harmonic Loss, Low-Torque Ripple Hall Sensor, Encoder 32bit
Sensorless Trapezoidal Drive Control BLDC High-Harmonic Loss, High-Torque Ripple Not Required (Back-EMF) 16bit
Sensorless Vector Control BLDC, AC Low-Harmonic Loss, Low-Torque Ripple Not Required 32bit