Converter Classification ECE 442 Power Electronics
First-Quadrant Converter Load Current iL flows into the load (+) Load Voltage is + Rectifier ECE 442 Power Electronics
Second-Quadrant Converter Load Voltage is + Load Current iL flows out of the load (-) Inverter ECE 442 Power Electronics
Second-Quadrant Converter ECE 442 Power Electronics
When the switch is closed E forces current through L, load voltage vL = 0 ECE 442 Power Electronics
When the switch is opened ECE 442 Power Electronics
ECE 442 Power Electronics
First and Second Quadrant Converter ECE 442 Power Electronics
S1 and D4 operate as a first-quadrant converter. S2 and D4D1 operate as a second-quadrant converter ECE 442 Power Electronics
Second Quadrant Operation 2 S2 closed S2 open ECE 442 Power Electronics
Third and Fourth Quadrant Converter The load voltage is always negative, but the load current is either positive or negative ECE 442 Power Electronics
Third Quadrant Operation S3 closed S3 open iL, vL are always negative ECE 442 Power Electronics
Fourth Quadrant Operation S2 closed load current +, load voltage – (zero) S2 open load current +, load voltage negative, (-Vs) ECE 442 Power Electronics
Four-Quadrant Converter Load Current can be positive or negative Load Voltage can be positive or negative For fourth quadrant operation, reverse E. ECE 442 Power Electronics
Summary of a four-quadrant converter ECE 442 Power Electronics
Summary of the conducting devices ECE 442 Power Electronics