682q Boost Converter Lecture 1
This document was uploaded by user and they confirmed that they have the permission to share it. If you are author or own the copyright of this book, please report to us by using this DMCA report form. Report DMCA
Overview
Download & View 682q Boost Converter Lecture 1 as PDF for free.
More details
- Words: 582
- Pages: 20
EE682 – Group Project Design Lecture #1 Power Switch Design
Prof. Ali Keyhani Boost DC/DC Converter Design
Power Switch Design
Boost Converter Review 1. Circuit topology
1/19
Power Switch Design
Boost Converter Review 2. Continuous conducting mode (CCM)
Current slope: VL/L Where VL is inductor voltage
2/19
Power Switch Design
Boost Converter Review 3. Discontinuous conducting mode (DCM)
Inductor current is not continuous
3/19
Power Switch Design
Design Tasks 1. Power switch design 2. Inductor design 3. Capacitor design 4. Drive circuit
4/19
Power Switch Design
Design Specifications 1. Input voltage: 24 V 2. Output voltage: 48 V 3. Output power: 240 W 4. Inductor current ripple: 15 % 5. Capacitor voltage ripple: 0.1 %
5/19
Power Switch Design
Power Switch Design 1. Power BJTs, Power MOSFETs, and IGBTs 1. BJTs – greater capacity, low ON state loss 2. MOSFETs – fast switching, voltage driven 3. IGBTs – combined modules, powerful and expensive
6/19
Power Switch Design
Power Switch Design Illustrate the design procedures with a design example: Design requirement: A 240-watt DC/DC boost converter with Vin=24V and Vout=48V.
7/19
Power Switch Design
Power Switch Design 1. Current and voltage rating requirements Design: Peak transistor current equals to Iin=P/Vin=240W/24V=10A Voltage rating requirements VTmax=Vout+VF(diode)=48+0.7V=48.7V 8/19
Power Switch Design
Power Switch Design 2. Device selection based on the requirements Design: Candidate I: BJT 2N6547 IC=15A>10A and VCE=400V>48V Candidate II: power MOSFET HUFA75307D3 ID=15A>10A and VDS=55V>48V
9/19
Power Switch Design
Power Switch Design Datesheet 2N6547
10/19
Power Switch Design
Power Switch Design Datesheet HUFA75307D3
11/19
Power Switch Design
Power Switch Design 3. Base/Gate drive requirements 2N6547: For IC=15A, must have IB>=3A, not desirable
12/19
Power Switch Design
Power Switch Design 3. Base/Gate drive requirements (cont’d) HUFA75307D3 is voltage driven: Threshold (mininum ON) gate-source voltage VGSth =4V Maximum gate-source voltage VGSmax=20V Can be driven by TTL (+5V) or CMOS logic +15V digital circuits
13/19
Power Switch Design
Power Switch Design 4. Transient performances 2N6547 Rise time: tr=1.0µs Fall time: tf=1.5µs HUFA75307D3 Rise time: tr=40ns Fall time: tf=45ns
14/19
Power Switch Design
Power Switch Design 5. Selection Power MOSFET HUFA75307D3 6. Switching loss Wloss 1 V I = (Wloss _ ON + Wloss _ OFF ) = ds d (tON + tOFF ) T T 2T 48 ×10 ( = 60 + 100)× 10 −9 = 0.768W 1 2× 20 × 103
PSW _ loss =
15/19
Power Switch Design
Power Switch Design 7. ON state loss 1. ON state time t1 =
1 Vout + VF − Vin 1 48 + 0.7 − 24 = sec = 25.73 µs 3 f Vout 48 20 ×10
2. ON state loss PON _ loss = =
WON _ loss T
(
1 2 = I D rDS ( ON )t1 T
(
) )
1 152 × 0.075 × 25.73 ×10 −6 = 8.684W 1 20 ×103
16/19
Power Switch Design
Power Switch Design 8. Overall loss
Ploss = PSW _ loss + PON _ loss = 9.452W < PD = 45 W (see the datasheet of HUFA75307D3)
17/19
Power Switch Design
Power Switch Design Calculation of junction to sink temperature difference
∆ T JC ( t ) = Ploss Z θ JC ( 50 %) ( t ) R θ JC ∴ ∆T js = Rθjs × Ploss = 3.3o C/W × 9.452W = 31.2o C < Tjmax = 175°C
18/19
Power Switch Design
Power Switch Design HUFA75307D3 ON-resistance and turn-on and turn-off time
19/19
Prof. Ali Keyhani Boost DC/DC Converter Design
Power Switch Design
Boost Converter Review 1. Circuit topology
1/19
Power Switch Design
Boost Converter Review 2. Continuous conducting mode (CCM)
Current slope: VL/L Where VL is inductor voltage
2/19
Power Switch Design
Boost Converter Review 3. Discontinuous conducting mode (DCM)
Inductor current is not continuous
3/19
Power Switch Design
Design Tasks 1. Power switch design 2. Inductor design 3. Capacitor design 4. Drive circuit
4/19
Power Switch Design
Design Specifications 1. Input voltage: 24 V 2. Output voltage: 48 V 3. Output power: 240 W 4. Inductor current ripple: 15 % 5. Capacitor voltage ripple: 0.1 %
5/19
Power Switch Design
Power Switch Design 1. Power BJTs, Power MOSFETs, and IGBTs 1. BJTs – greater capacity, low ON state loss 2. MOSFETs – fast switching, voltage driven 3. IGBTs – combined modules, powerful and expensive
6/19
Power Switch Design
Power Switch Design Illustrate the design procedures with a design example: Design requirement: A 240-watt DC/DC boost converter with Vin=24V and Vout=48V.
7/19
Power Switch Design
Power Switch Design 1. Current and voltage rating requirements Design: Peak transistor current equals to Iin=P/Vin=240W/24V=10A Voltage rating requirements VTmax=Vout+VF(diode)=48+0.7V=48.7V 8/19
Power Switch Design
Power Switch Design 2. Device selection based on the requirements Design: Candidate I: BJT 2N6547 IC=15A>10A and VCE=400V>48V Candidate II: power MOSFET HUFA75307D3 ID=15A>10A and VDS=55V>48V
9/19
Power Switch Design
Power Switch Design Datesheet 2N6547
10/19
Power Switch Design
Power Switch Design Datesheet HUFA75307D3
11/19
Power Switch Design
Power Switch Design 3. Base/Gate drive requirements 2N6547: For IC=15A, must have IB>=3A, not desirable
12/19
Power Switch Design
Power Switch Design 3. Base/Gate drive requirements (cont’d) HUFA75307D3 is voltage driven: Threshold (mininum ON) gate-source voltage VGSth =4V Maximum gate-source voltage VGSmax=20V Can be driven by TTL (+5V) or CMOS logic +15V digital circuits
13/19
Power Switch Design
Power Switch Design 4. Transient performances 2N6547 Rise time: tr=1.0µs Fall time: tf=1.5µs HUFA75307D3 Rise time: tr=40ns Fall time: tf=45ns
14/19
Power Switch Design
Power Switch Design 5. Selection Power MOSFET HUFA75307D3 6. Switching loss Wloss 1 V I = (Wloss _ ON + Wloss _ OFF ) = ds d (tON + tOFF ) T T 2T 48 ×10 ( = 60 + 100)× 10 −9 = 0.768W 1 2× 20 × 103
PSW _ loss =
15/19
Power Switch Design
Power Switch Design 7. ON state loss 1. ON state time t1 =
1 Vout + VF − Vin 1 48 + 0.7 − 24 = sec = 25.73 µs 3 f Vout 48 20 ×10
2. ON state loss PON _ loss = =
WON _ loss T
(
1 2 = I D rDS ( ON )t1 T
(
) )
1 152 × 0.075 × 25.73 ×10 −6 = 8.684W 1 20 ×103
16/19
Power Switch Design
Power Switch Design 8. Overall loss
Ploss = PSW _ loss + PON _ loss = 9.452W < PD = 45 W (see the datasheet of HUFA75307D3)
17/19
Power Switch Design
Power Switch Design Calculation of junction to sink temperature difference
∆ T JC ( t ) = Ploss Z θ JC ( 50 %) ( t ) R θ JC ∴ ∆T js = Rθjs × Ploss = 3.3o C/W × 9.452W = 31.2o C < Tjmax = 175°C
18/19
Power Switch Design
Power Switch Design HUFA75307D3 ON-resistance and turn-on and turn-off time
19/19
Related Documents
682q Boost Converter Lecture 1
June 2020 7
682q Boost Converter Lecture 2
June 2020 13
Analysis Converter Buck Boost
June 2020 7
Converter
November 2019 26
Boost My English 1
May 2020 6
Semi Converter 1 Phasa
May 2020 4More Documents from ""
682q Boost Converter Lecture 1
June 2020 7
How To Use Simulink
June 2020 19
Arc Detection Poster
June 2020 7
682q Boost Converter Lecture 2
June 2020 13
Static Switching
June 2020 10