A softstarter is replica of a star-delta starterin which
starting current is controlled by reducing voltage using ac
voltage controller for smooth starting.As Ac voltage
controllers are not suitable for speed control.So,soft
starters are mainly used for starting purpose only.(since
in Ac voltage controller,frequency is fixed,only voltage
has to be varied.Also,It produces predominant harmonics
into the system.
You can divide the world of electronic motor drives into
two categories: AC and DC. A motor drive controls the speed,
torque, direction and resulting horsepower of a motor. A DC
drive typically controls a shunt wound DC motor, which has
separate armature and field circuits. AC drives control AC
induction motors, and-like their DC counterparts-control
speed, torque, and horsepower.
in thermal power plant the steam produced is made to cool
after falling on the turbine blades.
my question is why this is done while the same is needed to
heat up again.
"jab pani ko wapis garam hi karna hai to thanda kyu karte