Question

A voltage commutated chopper operating at 1 kHz is used to control the speed of dc motor as shown in figure. The load current is assumed to be constant at 10A.
The minimum average output voltage of the chopper will be

Answer 1

$\left(V_0\right)=V_s\left[\frac{T_{ON}+2t_{cm}}{T}\right]$

$where,t_{cm}=\frac{C{V}_s}{I_0}=\frac{1\times {10}^{-6}\times \times 250}{10}$

$(V_0{)}_{min}=V_s[(T_{ON}{)}_{min}+2t_{cm}]f$

$=250[140\times {10}^{-6}(2\times 25\times {10}^{-6}\left)\right]\times (1\times {10}^3)=47.5V$