ELE 754 Midterm: ELE 754 Fall 2010 Midterm Solution

• School: Ryerson University
• Department: Electrical Engineering
• Course: ELE 754
• Professor: All

Document Summary

Marks will be lost if there is no appropriate units. Consider the buck converter with controller shown in figure 1. Vd =48 v, switching frequency fw =100 khz, output voltage is maintained at vo = 18 v, and the duty cycle d is adjusted by the controller to keep the output voltage constant. Answer the following questions, assuming that the inductance is the minimum inductance in 1. 1). V (~d -"7 u= -~i~ 7)( r-?/) = ir. 1. 4) if the load resistance is increased to lon, find the duty cycle when the output voltage is maintained at 18v. 11. :: j 0 c1l0 ) 1"~ ly,o = ("s,4(cid:173) 1. 5) use the template and draw the following waveforms. ~ l. ~. 1) 15- ~. o-d~ _ b it~ oil t17 ) If!0 a) the voltage waveform across the dc choke vl " b) the voltage waveform across the switch v sw" c) the switch current id , d) the inductor current il .