Description

Brushed motors are a relatively popular option for motor designs because of their low price and simple control scheme.  A brushed motor has a wire-wound rotor and permanent magnet stator.  The commutation of the motor is achieved using conductive rings that are connected to the rotor using brushes that scrape against the commutator rings.  This allows the direction of current through the motor to change based on the orientation of the brushes and different commutation rings.  Utilizing an H-Bridge allows for easy direction and speed control changes to be applied quickly and efficiently to the brushed DC motor.  An electronic drive is required to control the motor currents in a brushed DC motor.  The electronic drive circuit consists of a power stage with two-phase inverter meeting the required power capability: a microcontroller to implement the motor speed commands and fault handling: current sensing for motor startup / stall protection: gate driver for controlling the two-phase inverter: and a power supply for microcontroller and other low voltage devices.