A 3-phase diode bridge rectifier is fed from a 415V, 50HZ supply which has negligible impedance. The rectifier output is smoothed by a series inductance of 2mH followed by a parallel capacitor (LC smoothing), which may be large enough so that it voltage is smooth. A load is connected in parallel with the capacitor. 

a) At a particular condition the current drawn is such that the inductor current is continuous. 

i) Calculate the load voltage and draw a neat diagram defining the voltage-time-area appearing across the smoothing inductor. 

ii) Determine the peak to peak ripple in the smoothing inductor current. 

b) The load current is now reduced below the value in part (a) causing the inductor current to become discontinuous and the load voltage to rise to 570V. 

i) Determine the peak inductor current. 

ii) Show that a good estimate for the duration of each current pulse in the inductor is 41.35° of the supply voltage period. 

iii) Determine an estimate for the mean load current stating any assumptions that you make.

Answer rating: 100% (QA)

Solution Given 3 phase diode bridge rectifier Input Voltage 415 V Line to Line rms frequency 50 Hz F... View the full answer