28-05-2010, 07:58 PM
Pulse Width Modulation is widely used in power electronics as a controller in power conversion and motion control. Among different types of modulating modes the Sinusoidal Pulse Width Modulation (SPWM) and Space Vector PWM are two common strategies in adjustable speed drive system. The Pulse width of SPWM varies with the Sine wave so as to restrain the lower order harmonics with easy control and large D C utilization. With successively improving reliability and performance of digital controllers, the digital control techniques have predominated over other analog counter parts. The advantages of digital controllers are:
a) Reconfigurability
b) P ower saving options
c) Less external passive components
d) Less sensitive to temperature variation