Engineering Q&A
Give the effect of source impedance on converter operation.
in Power Electronics by
retagged by

1 Answer

0 like 0 dislike

Effect of source impedance on converter operation: For single-phase fully controlled bridge converter, the SCRs are triggered in pairs alternately. During positive half-cycle of input, SCRs T1 and T2 are triggered whereas during negative half-cycle, SCRs T3 and T4 are triggered. When T1 and T2 are conducting, T3 and T4 are off. On the reversal of supply voltage, firing of T3 and T4 causes application of reverse bias across T1 and T2 and they are turned off. The current shifts from T1 T2 to T3 T4. The instantaneous current shift is possible only when the voltage source has no internal impedance. In practice, the source always possesses some internal impedance may be due to the transformer on supply side. 1) If the source impedance is purely resistive, then voltage drop across it causes reduction in input voltage and ultimately in the output voltage of converter. 2) If the source impedance is largely inductive, then source current cannot change instantly. The current cannot get transferred immediately from outgoing SCRs to incoming SCRs. The commutation of SCRs is delayed. During current transfer, both pairs of SCRs conduct simultaneously and load voltage appears zero. As both pairs of SCRs conduct simultaneously, this commutation period is called “overlap period (μ)”. The output dc voltage is given by,

image 

As source inductance (Ls) increases, the commutation period (overlap angle μ) increases and as a consequence, the output dc voltage decreases. 


image

image

by

Related questions

1 answer
1 answer
asked Jun 11, 2019 by anonymous1 | 46 views
1 answer
asked Feb 12, 2018 in Unit 2 by Quiz | 54 views
1 answer
asked Feb 12, 2018 in Unit 2 by Quiz | 150 views
1 answer
asked Sep 18, 2017 in Unit 2 by Quiz | 101 views
1 answer
asked Sep 18, 2017 in Unit 2 by Quiz | 124 views
1 answer
asked Aug 6, 2017 in Unit 2 by Zeeshan | 140 views
Welcome to electronics2electrical.com, where students and teachers can ask and answer any question. Get help and answers to any engineering problem including Electrical, electronics, mechanical, telecommunication, instrumentation, computer, mathematics, physics etc. Get answers to questions. Help is always 100% free!

Most popular tags

power motor dc circuit transformer voltage current system used phase resistance factor ac load synchronous induction energy electric generator electrical series frequency capacitor between plant line speed transmission use meter type advantages difference single mosfet control function instrument problem magnetic amplifier high diode bjt machine unit source motors and diagram winding shunt field parallel define electricity torque value maximum time relay types arduino supply digital armature applications thyristor working transformers wave on flow operation three coil material instruments state ratio signal emf effect formula efficiency theorem method disadvantages starting microprocessor network test operating direction controlled different logic transistor single-phase scr loss temperature connected rc law force inductance compare measure station wire low conductor principle wattmeter full characteristics measuring constant measurement breaker losses device converter bridge linear materials nuclear matrix flux drive resistivity of machines angle switch free rectifier protection core circuits battery solar gain thermal loop generators open negative analog number lines friction reactance short gate pole inverter the conservation diesel iron resistors capacitance engineering basic using direct main electronic electronics a steam induced relays hysteresis universal transducer computer feedback range distribution work secondary igbt algebra pmmc plants factors capacitors dielectric controller regulation systems design air fault components rotor cable starter oscillator eddy alternator application semiconductor ammeter rl average forces damping rlc connection zener electromagnetic biasing minimum insulation pressure balanced permanent moving errors running copper self analysis impedance stability quality start ideal curve over commutation is 3-phase arc permeability peak bias error fuzzy commutator conductors superposition density mechanical rotation construction measured electrons charge memory inductive two transfer explain fuse methods off back three-phase tariff locomotive installation welding heating rms surge rating generation potentiometer coupled shaded rate capacity storage adc excitation active pure resistor harmonics reluctance microcontroller voltmeter inductor internal 8085 cro reaction insulating overhead hydro resonance traction definition breakers earth

9,192 questions

7,942 answers

156 comments

3,291 users

9,192 questions
7,942 answers
156 comments
3,291 users