Speed control of DC Motor
The DC motor are versatile motors among the available electrical motors due to their superior characteristics. These motors give a smooth speed control over a wide range. The main advantage so using DC motors in industrial applications include ability of providing high starting torque required specially in traction applications possible speed control over wide range both above and below the base speed simplicity and easiness in speed control methods and importantly less expensive than those of AC motors. The men disadvantage with DC motors is the presence of commutate which limit its use in high speed applications and require more maintenance than AC motors .
a.Controlled rectifies or phase controlled converters which give a variable de output from a fixed ac voltage .
b.Choppers which provide variable dc output voltage from a fixed dc input voltage.