"The problem with the cheap ones," says Dave Wilson, director at the Fareham site in charge of all testing operations, "is that they have an open
commutator motor and no suppression at all and they're usually housed in some cheap plastic."
In addition, the plant produces low-power
commutator motors used in production of household goods.
All are kicking out brushed
commutator motors and most have replaced them with permanent magnet (PM) AC brushless motors - today's winner with about 70 percent of the numbers of motors in electric vehicles.
Information about the motor's rotor position can be supplied to the positioning controller either by the voltage or by an encoder in the case of
commutator motors or, for brushless motors, by Hall sensors or an incremental encoder.
Individual chapters are provided concerning permanent magnet DC
commutator motors, permanent magnet synchronous motors, DC brushless motors, axial flux motors, high power density brushless motors, brushless motors of special construction, and stepping motors.