In a buck converter, consider all components to be ideal. Let the output voltage level to be constant at Vo-10 V by controlling the switch duty ratio D. 

Calculate the minimum inductance L required to keep the converter operation in a continuous conduction mode under all conditions if the input voltage, Vd is in the range of 20- 50 V, output power, Po ≥ 10 W, and switching frequency, fs = 20 kHz.