Half Bridge Inverter
Q. What is half bridge inverter?
Q. Single Phase Half Bridge Inverter Explained
Q. Half H-Bridge Inverter
Circuit Diagram of Half Bridge Inverter :
- Figure A shows the circuit diagram of a half bridge inverter.
- Only two thyristors S1 and S2, are used along with the feed-back diodes D1 and D2, connected across them. It is important to note that we can use any power device such as power transistor, power MOSFET of IGBT in place of the two SCRS S1 and S2 in this circuit.
- The DC power supply has been divided into two halves each one having a terminal voltage of V2 volts.
- The triggering and commutation circuits for SCRs have not been shown.
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| Figure A |
Operation of Half Bridge Inverter with resistive load :
- The thyristor S1 is turned on at t = 0 for a time T0/2, which makes the instantaneous voltage across the load V = V / 2.
- If thyristor S2 is turned on at instant T0/2, by turning S1 off then – V / 2 appears across the load. Thus a square wave is produced across the load.
- A precaution must be taken while designing the control circuit so that both the thyristors are not turned on simultaneously, as it will short circuit the source and may damage the thyristors.
Waveforms of Half Bridge Inverter :
- Figure B shows the waveforms of output voltage and thyristor currents with a resistive load. The voltage across the thyristor when it is off is V and not V / 2.
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| Figure B |