modulation ratio การใช้

• When the AC output is at frequency fc with its amplitude at v c, and the triangular carrier signal is at frequency f ? with its amplitude at v ?, the PWM becomes a special sinusoidal case of the carrier based PWM . This case is dubbed sinusoidal pulse-width modulation ( SPWM ) . For this, the modulation index, or amplitude-modulation ratio, is defined as "'v c / v  " } } " '.