design of single phase inverter using mosfets

Slide 1:

DESIGN OF SINGLE PHASE INVERTER USING MOSFETS PRESENTED BY P.PONVASANTH P.R.SURYA (1 ST ME PE&D) GUIDED BY Mr. M. KALIAMOORTHY

CONTENTS:

CONTENTS What is an inverter History of inverter Diagram of the inverter Why MOSFET is preferred Control circuit Procedure Wave forms obtained Applications Designed circuit Conclusion

INTRODUCTION:

INTRODUCTION An inverter is a device that changes or inverters direct current (DC) input to alternating current(AC) output. It doesn't "create" or "make" electricity, just changes it from one form to another. DC in is changed to AC out. Output is usually 230 volts at 50-cycle alternating current to match line power.

INTRODUCTION (cont’d):

INTRODUCTION (cont’d) Inverters are often a good choice for applications that require the main engine to operate at a job site. i.e. powering hydraulic systems or air compressors. Since, inverters are electronic devices, we don't have the noise from a separate engine. An inverter requires no fuel and virtually no maintenance Since, inverter output is fully voltage and frequency regulated and functions independently from the speed of the engine.

HISTORY OF INVERTER:

HISTORY OF INVERTER From the late nineteenth century through the middle of the twentieth century, DC-to-AC power conversion was accomplished using rotary converters or motor-generator sets (M-G sets). In the early twentieth century, vacuum tubes and gas filled tubes began to be used as switches in inverter circuits

DIAGRAM OF THE INTERVER:

DIAGRAM OF THE INTERVER SINGLE PHASE INVERTER USING MOSFETS

WHY MOSFET IS PREFERRED:

WHY MOSFET IS PREFERRED The MOSFET, however, is a device that is voltage- and not current-controlled. MOSFETs have a positive temperature coefficient, stopping thermal runaway. The on-state-resistance has no theoretical limit, hence on-state losses can be far lower. The MOSFET also has a body-drain diode, which is particularly useful in dealing with limited free wheeling currents.

CONTROL CIRCUIT:

CONTROL CIRCUIT

OPTO ISOLATOR CIRCUIT:

OPTO ISOLATOR CIRCUIT

PROCEDURE TO PRODUCE CONTROL PULSES:

PROCEDURE TO PRODUCE CONTROL PULSES In control circuit block first generate square pulse by using 555 timer circuit. Obtained square pulse is fed to the IC74121 (1). Output from the 555 timer circuit as well as the output of the IC74121 (1) is fed to the XOR gate IC74C86 (1). By using the NOT gate IC7404 the output square wave is inverted and it is fed to another IC74121 (2). Output from the NOT gate as well as the output of the IC74121 (2) is fed to the gate IC74C86 (2). Both the outputs from the IC74C86 (1, 2) are fed to the optoisolator and drive circuits (1, 2).

PROCEDURE TO PRODUCE CONTROL PULSES (cont’d):

PROCEDURE TO PRODUCE CONTROL PULSES (cont’d) The optoisolator and drive circuits output are fed as triggering pulse to the MOSFETs. The optoisolator-1 provides control pulses to T 1 and T 2 and the optoisolator-2 provides control pulses to T 3 and T 4. The control pulses are viewed with the help of Digital storage Oscilloscope. Thus the control pulses are obtained and then it is fed to the power circuit and final waveforms are obtained. Thus the control pulses are obtained and then it is fed to the power circuit and final waveforms are obtained.

CONTROL CIRCUIT WAVEFORMS:

CONTROL CIRCUIT WAVEFORMS

CONTROL PULSES OBTAINED:

CONTROL PULSES OBTAINED Control pulses for “T1,T2 & T3 ,T4” MOSFETS

CONTROL PULSES OBTAINED (cont’d):

CONTROL PULSES OBTAINED (cont’d) Delay pulses for “T1 &T2” MOSFETS Delay pulses for “T3 &T4” MOSFETS

CONTROL PULSES OBTAINED (cont’d):

CONTROL PULSES OBTAINED (cont’d) Control pulses for “T1 &T2” MOSFETS Control pulses for “T3 &T4” MOSFETS

APPLICATIONS:

APPLICATIONS DC Power source utilization Uninterruptible power supplies Induction heating HVDC power transmission Variable-frequency drives Electric vehicle drives The general case

PHOTO SHOT OF DESIGNED CIRCUIT:

PHOTO SHOT OF DESIGNED CIRCUIT

CONCLUSION:

CONCLUSION Inverter is a simple but versatile circuit. It is Extensively used as buffer in the output stage to reduce the loading effect of the previous stage. Used as a basic block in many analog circuits like oscillators, Amplifiers.

Slide 19:

THANK YOU