Buck-Boost Converter
-
Upload
sagar-patil -
Category
Engineering
-
view
2.589 -
download
3
Transcript of Buck-Boost Converter
A PROJECT ON
PRSENTED BY: NAME EXAM SEAT NO.KIRTIKUMAR PATIL W3094051SAGAR PATIL W3094052GOPAL PAWASKAR W3094053
BUCK-BOOST CONVERTER
GUIDED BY: DR.D.S.MORE
INTRODUCTION
Buck-boost converter operates on dc supply
Buck operationBoost operationDuty ratio of control signal defines
its operation
CONTROL CIRCUIT
OPERATION OF CONTROL CIRCUIT
To drive the mosfet op-amp based circuit is designed
Op-amp(A) is used as an integratorOp-amp(B) and op-amp(c) is used as a
comparatorTransistor 2N5294 is used as a switch to provide
control signalFrequency and duty ratio of output signal can be
controlled by using potentiometer in this circuit
Output waveform of Op-amp(A)
Output waveform of Op-amp(B)
Output waveform of control circuit
POWER CIRCUIT
OPERATION OF POWER CIRCUITStep 1: when mosfet is ON
Voltage across inductor L is equal to V
(source voltage)
Step 2: when mosfet is OFF
Voltage across inductor L is equal to Vo (in reverse direction)
Here output voltage developed across load is Vo
Step 3: When mosfet is ON in next cycleLoad is isolated from voltage sourceIn this case charged capacitor across load
will maitain voltage across load
DUTY RATIODuty ratio(D) is defined as Ton/T here, Ton=ON time T=time period of gate
signal D=Ton/T Ton=DT T=Ton+Toff Toff=T-Ton Toff=(1-D)T
VOLTAGE ACROSS INDUCTORWhen mosfet is ON, voltage across inductor is
equal to source voltage(V).When mosfet is OFF, voltage across inductor is
equal to output voltage(Vo)As average voltage across inductor is zero Hence, V*D*T=Vo*(1-D)*T Vo=V* D 1-D
Vo=V* D 1-DThis equation shows that output voltage
depends on duty ratio(D) For buck operation D=0 to 0.5 For boost operation D=0.5 to 1
APPLICATIONSUsed in many industrial applications
such as subway cars, trolley buses, battery operated vehicles, battery charging etc.
To provide smooth control on output, high efficiency, fast response and regeneration.
To provide efficient control on dc motor operation
To provide long life and less maintenance due to absence of moving parts.
THANK YOU!