Design of DC-DC Converter Bench Controlled by an Arduino Microcontroller

Design of DC-DC Converter Bench Controlled by an Arduino Microcontroller

Moez Youssef 1

1 Associate Professor,

Department of Electromechanical Engineering, Military Academy, Foundouk Jedid, Nabeul, Tunisia.

Chokri Boubahri 3

3 Assistant Professor,

Department of Electromechanical Engineering, Military Academy, Foundouk Jedid, Nabeul, Tunisia.

Fethi Aloui 2

2 Assistant Professor,

Department of Electromechanical Engineering, Military Academy, Foundouk Jedid, Nabeul, Tunisia.

Seifallah Fetni 4

4 Assistant,

Department of Electromechanical Engineering, Military Academy, Foundouk Jedid, Nabeul, Tunisia.

Abstract The main purpose of this paper is to design a DC- DC converter bench controlled by an Arduino board. This DC- DC converter bench is dedicated to the teaching of Power Electronics Labs. Several DC-DC converters topologies can be studied. Proteus simulations were carried out for the different structures.

KeywordsDC-DC converters; Arduino; Proteus simulations

1. INTRODUCTION

   A power converter circuit manages the flow of electrical energy between a source and a load. Until a few years ago, their primary use was in supplying motors in industrial applications and in electric traction systems. Nowadays, in addition to those fields, they are employed in very wide range of applications including domestic applications, renewable energy systems, FACTS (Flexible Alternating Current Transmission System), automotive

   Innovations in the field of power converters are taking place on several axes: new generation of power semiconductors, more and more new configurations of power converters, the use of digital devices such as microcontrollers, FPGA (Field Programmable Gate Arrays) in control circuits.

   Modern power converters offer a high grade of precision, flexibility, communication capability, reliability to the end user, with smaller sizes.

   This paper presents the design of DC-DC converter bench controlled by an Arduino card. Experiments and Proteus simulations are carried out for elementary structures of DC- DC converters such as buck, boost, buck-boost converters.

   A block diagram of the experimental bench is shown in Fig.1. A DC power source, mostly battery is used to power the DC-DC converter. The pulse needed for switching the semiconductor is generated from the Arduino UNO. The code is written with the open-source Arduino Software (IDE). The measurement of the different currents and voltages can be done either by the Arduino card or by an oscilloscope.

   DC Power Source

   DC-DC

   converter

   Load

   DC Power Source

   DC-DC

   converter

   Load

   Arduino controller

   Arduino controller

   Computer

   Computer

   Fig.1: Block diagram

2. CONTROL CIRCUIT The control circuit is shown in Fig.2.

   Vcc

   Vcc

   Power MOSFET

   Power MOSFET

   R

   R

   R

   T

   vGS

   5V

   0

   From PIN 7

   of the arduino

   R

   T

   vGS

   5V

   0

   From PIN 7

   of the arduino

   vin

   vin

   Fig.2: Control circuit

   R2(1)

   R2(1)

   The type and the values of the components used are as follows:

   DUINO1

   DUINO1

   RESET

   RESET

   AREF

   PB5/SCK 13

   PB4/MISO 12

   AREF

   PB5/SCK 13

   PB4/MISO 12

   microcontrolandos.blogspot.com

   microcontrolandos.blogspot.com

   TABLE I. components of the control circuit

   T: NPN transistor	2N2222
   R: resistor	1k
   Vcc: DC source	15V

   R2

   1k

   T: NPN transistor	2N2222
   R: resistor	1k
   Vcc: DC source	15V

   R2

   1k

   ~PB3/MOSI/OC2A 11

   ~ PB2/SS/OC1B 10

   ~ PB1/OC1A 9

   ~PB3/MOSI/OC2A 11

   ~ PB2/SS/OC1B 10

   ~ PB1/OC1A 9

   A

   A

   PB0/ICP1/CLKO 8

   PD7/AIN1 7

   PB0/ICP1/CLKO 8

   PD7/AIN1 7

   R1

   1k

   R1

   1k

   Q1

   2N2222

   Q1

   2N2222

   B

   B

   A0

   A0

   ~PD6/AIN0 6

   ~PD6/AIN0 6

   C

   C

   A1 PC0/ADC0

   A1 PC0/ADC0

   ~ PD5/T1 5

   ~ PD5/T1 5

   A2 PC1/ADC1

   A2 PC1/ADC1

   PD4/T0/XCK 4

   PD4/T0/XCK 4

   D

   D

   A3 PC2/ADC2

   A3 PC2/ADC2

   ~ PD3/INT1 3

   ~ PD3/INT1 3

   ANALOG IN

   ANALOG IN

   1121

   ATMEGA328P-PU

   1121

   ATMEGA328P-PU

   Vin is the voltage delivered by the PIN7 of the Arduino. Vin is a square-wave voltage, the low level is 0V and the high level is 5V. In order to have a square-wave voltage with a frequency f=1kHz and a duty cycle D=0.6, the following code must be written with the Arduino Software (IDE).

   Fig.3: Arduino code

   When Vin is at the low level (0V), the transistor T is OFF (open), then vGSVcc=15V (for R=1k , the voltage across the resistor R can be neglected).

   When Vin is at the high level (5V), the transistor T is ON (saturated), then vGS0V.

   Fig.4 shows a simulation of the control circuit on Proteus.

   A4 PC3/ADC3

   A5 PC4/ADC4/SDA PC5/ADC5/SCL

   PD2/INT0 2

   TX PD1/TXD 1

   RX PD0/RXD 0

   A4 PC3/ADC3

   A5 PC4/ADC4/SDA PC5/ADC5/SCL

   PD2/INT0 2

   TX PD1/TXD 1

   RX PD0/RXD 0

   ARDUINO UNO R3

   ARDUINO UNO R3

   DIGITAL (~PWM)

   DIGITAL (~PWM)

   Fig.4: Proteus simulation of the control circuit

   The result of the control circuit simulation is as follows.

   Fig.5: control voltage simulation

   After simulation, the complete control circuit has been tested, the following result is obtained:

   Fig.6: control voltage measured

3. POWER CIRCUIT

   Experiments are carried out for three DC-DC converters structures that are: Buck converter, Boost converter and Buck- Boost converter.

   The type and the values of the components used are as follows:

   TABLE II. Components of the power circuit

   M: MOSFET	IRF540
   D: Diode	BYY56
   R: Resistor	25
   L: Inductor	0.1H
   C: Capacitor	54µF
   VS: DC source	15V

   A. Buck converter

   The buck converter is shown in Fig.7. It operates by periodically opening and closing an electronic switch (MOSFET). It is called a buck converter because the output voltage is less than the input.

   M

   i

   u(t) VS

   u(t) VS

   t

   t

   D.T

   T

   D.T+T

   D.T

   T

   D.T+T

   i(t)

   i(t)

   t

   t

   D.T

   T

   D.T+T

   D.T

   T

   D.T+T

   Fig.9: Theoretical waveforms of the buck converter

   u(t) and i(t) are output (load) voltage and current. The average of the output voltage u(t) is given by:

   VS D

   u L

   D is the duty cycle.

   R B. Boost converter

   = .

   (1)

   Fig.7: Buck converter

   S

   S

   D

   D

   In practice, the following configuration (Fig.8) is preferred. Its main advantage is the common ground for both control and power circuits.

   i

   V

   u/p>

   L

   i

   V

   u

   L

   R

   R

   M

   M

   Control

   voltage

   Control

   voltage

   Fig.8: Buck converter with common ground

   Theoretical waveforms for buck converter are as follows:

   The boost converter is shown in Fig.10. It is called a boost converter because the output voltage is larger than the input.

   L

   vL

   D

   L

   vL

   D

   M

   M

   Control voltage

   Control voltage

   u

   u

   V

   V

   vM

   vM

   C R

   C R

   S

   S

   Fig.10: Boost converter

   In theory, the capacitor C is considered so large that the output voltage u is held constant at = .

   The analysis proceeds by examining the inductor voltage (vL) and the switch voltage (vM) for the switch closed and again for the switch open.

   L

   vL U

   VS vM

   Fig.11: Equivalent circuit for the switch closed

   When the switch is closed:

   (2)

   (2)

   =

   { = 0

   L

   vL

   VS

   vM

   U

   vL

   D

   C R

   L

   vL

   VS

   vM

   U

   vL

   D

   C R

   M

   M

   VS

   VS

   L

   L

   u

   u

   Control voltage

   Control voltage

   Fig.12: Equivalent circuit for the switch open

   When the switch is open:

   =

   { = (3)

   Theoretical waveforms for boost converter are as follows:

   ()

   ()

   t

   t

   D.T

   T

   D.T+T

   D.T

   T

   D.T+T

   ()

   ()

   t

   t

   D.T

   T

   D.T+T

   D.T

   T

   D.T+T

   Fig.13: Theoretical waveforms of the boost converter

   The average inductor voltage must be zero for periodic operation, then:

   Fig.15: Buck-boost converter with common ground

   In theory, the capacitor C is considered so large that the output voltage u is held constant at = .

   L

   L

   C R

   C R

   The analysis proceeds by examining the inductor voltage (vL) for the switch closed and again for the switch open.

   vL

   VS

   vL

   VS

   U

   U

   Fig.16: Equivalent circuit for the switch closed

   When the switch is closed:

   = (6)

   Which gives:

   . + (1 )( ) = 0 (4)

   vL

   C R

   vL

   C R

   VS

   VS

   L

   L

   U

   U

   = (5)

   1

   Since 0 1, then

   C. Buck-boost converter

   L

   L

   L

   L

   C R

   C R

   The buck-boost converter is shown in Fig.14. The output voltage of the buck-boost converter can be either higher or lower than the input voltage.

   M

   v

   D

   VS

   M

   v

   D

   VS

   u

   u

   Fig.14: Buck-boost converter

   In practice, the following configuration (Fig.15) is preferred. Its main advantage is the common ground for both control and power circuits.

   Fig.17: Equivalent circuit for the switch open

   When the switch is open:

   = (7)

   Theoretical inductor voltage for buck-boost converter is as follows:

   ()

   ()

   t

   t

   D.T

   T

   D.T+T

   D.T

   T

   D.T+T

   Fig.18: Theoretical inductor voltage for buck-boost converter

   The average inductor voltage must be zero for periodic operation, then:

   Which gives:

   . + (1 ) × () = 0 (8)

   = .

   1

   (9)

   If 0.5 < , > : the output voltage is larger than the input.

   If < 0.5 , < : the output voltage is smaller than the input.

4. SIMULATIONS AND RESULTS

   In this section, Proteus simulations and real measurements are shown for the three configurations of DC-DC converters.

   1. Buck converter

      The complete buck converter circuit (control + power) is simulated using the Proteus software. Simulation is carried out for the practical values.

      Fig.21: Measured load current and voltage for buck converter

   2. Boost converter

      The complete boost converter circuit (control + power) is simulated using the Proteus software. Simulation is carried out for the practical values.

      A

      A

      B C

      D

      L1

      100mH

      D1

      DIODE

      B C

      D

      L1

      100mH

      D1

      DIODE

      R3

      25

      V1

      15V

      R3

      25

      V1

      15V

      DUINO1

      DUINO1

      R2(1)

      DUINO1

      R2(1)

      R2

      1k

      R2

      1k

      AREF

      PB5/SCK 13

      PB4/MISO 12

      AREF

      PB5/SCK 13

      PB4/MISO 12

      Q2

      NMOSFET

      Q2

      NMOSFET

      RESET

      RESET

      microcontrolandos.blogspot.com

      microcontrolandos.blogspot.com

      RESET

      ~PB3/MOSI/OC2A 11

      ~ PB2/SS/OC1B 10

      ~ PB1/OC1A 9

      ~PB3/MOSI/OC2A 11

      ~ PB2/SS/OC1B 10

      ~ PB1/OC1A 9

      A B C D

      microcontrolandos.blogspot.com

      microcontrolandos.blogspot.com

      AREF

      PB5/SCK 13

      PB4/MISO 12

      ~PB3/MOSI/OC2A 11

      ~ PB2/SS/OC1B 10

      ~ PB1/OC1A 9

      1121

      ATMEGA328P-PU

      1121

      ATMEGA328P-PU

      PB0/ICP1/CLKO 8

      DIGITAL (~PWM)

      DIGITAL (~PWM)

      ANALOG IN

      ANALOG IN

      R1

      R2(1)

      R2

      1k

      Q1

      C1

      54uF

      D1

      DIODE

      R3

      25

      Q2

      NMOSFET

      L1

      100mH

      V1

      15V

      PB0/ICP1/CLKO 8

      PD7/AIN1 7

      PB0/ICP1/CLKO 8

      PD7/AIN1 7

      R1

      1k

      R1

      1k

      Q1

      2N2222

      Q1

      2N2222

      DIGITAL (~PWM)

      DIGITAL (~PWM)

      1121

      ATMEGA328P-PU

      1121

      ATMEGA328P-PU

      PD7/AIN1 7

      2N2222

      ANALOG IN

      ANALOG IN

      A0 PC0/ADC0

      A0

      A0

      ~PD6/AIN0 6

      ~PD6/AIN0 6

      A1 PC1/ADC1

      A1 PC0/ADC0

      A1 PC0/ADC0

      ~ PD5/T1 5

      ~ PD5/T1 5

      A2 PC2/ADC2

      A2 PC1/ADC1

      A2 PC1/ADC1

      PD4/T0/XCK 4

      PD4/T0/XCK 4

      A3 PC3/ADC3

      A3 PC2/ADC2

      A3 PC2/ADC2

      ~ PD3/INT1 3

      ~ PD3/INT1 3

      A4 PC3/ADC3

      A5 PC4/ADC4/SDA PC5/ADC5/SCL

      A4 PC3/ADC3

      A5 PC4/ADC4/SDA PC5/ADC5/SCL

      PD2/INT0 2

      TX PD1/TXD 1

      RX PD0/RXD 0

      PD2/INT0 2

      TX PD1/TXD 1

      RX PD0/RXD 0

      A4 PC4/ADC4/SDA A5 PC5/ADC5/SCL

      ARDUINO UNO R3

      ~PD6/AIN0 6 1k

      ~ PD5/T1 5

      PD4/T0/XCK 4

      ~ PD3/INT1 3

      PD2/INT0 2

      TX PD1/TXD 1

      RX PD0/RXD 0

      ARDUINO UNO R3

      ARDUINO UNO R3

      Fig.19: Proteus simulation of the buck converter

      Fig.20: Proteus waveforms

      The yellow waveform represents the load current and the red waveform represents the load voltage.

      Practical Measurements are in accordance with theory and simulation as shown in Fig.21.

      Fig.22: Proteus simulation of the boost converter

      Fig.23: Proteus waveforms of the boost converter

      The yellow waveform represents the switch voltage and the red waveform represents the load voltage . Since the capacitor C has a finite value (C=54µF), the output voltage u is not constant (it has a ripple). Practical measurements confirm Proteus simulation as shown in Fig.24.

      Fig.24: Measured load and switch voltages for boost converter

   3. Buck boost converter

   D

   D

   L1

   100mH

   L1

   100mH

   V1

   15V

   V1

   15V

   microcontrolandos.blogspot.com

   microcontrolandos.blogspot.com

   The complete buck-boost converter circuit (control + power) is simulated using the Proteus software. Simulation is carried out for the practical values

   D1

   <>D1

   A

   DIODE

   A

   DIODE

   B

   C

   C1

   54uF

   R3

   25

   B

   C

   C1

   54uF

   R3

   25

   DUINO1

   R2(1)

   DUINO1

   R2(1)

   R2

   1k

   R2

   1k

   A4 PC3/ADC3

   A5 PC4/ADC4/SDA PC5/ADC5/SCL

   PD2/INT0 2

   TX PD1/TXD 1

   RX PD0/RXD 0

   A4 PC3/ADC3

   A5 PC4/ADC4/SDA PC5/ADC5/SCL

   PD2/INT0 2

   TX PD1/TXD 1

   RX PD0/RXD 0

   ARDUINO UNO R3

   ARDUINO UNO R3

   AREF

   PB5/SCK 13

   PB4/MISO 12

   AREF

   PB5/SCK 13

   PB4/MISO 12

   Q2

   NMOSFET

   Q2

   NMOSFET

   RESET

   RESET

   ~PB3/MOSI/OC2A 11

   ~ PB2/SS/OC1B 10

   ~ PB1/OC1A 9

   PB0/ICP1/CLKO 8

   ~PB3/MOSI/OC2A 11

   ~ PB2/SS/OC1B 10

   ~ PB1/OC1A 9

   PB0/ICP1/CLKO 8

   R1

   R1

   PD7/AIN1 7

   PD7/AIN1 7

   Q1

   2N2222

   Q1

   2N2222

   A0

   A0

   ~PD6/AIN0 6 1k

   ~PD6/AIN0 6 1k

   A1 PC0/ADC0

   A1 PC0/ADC0

   ~ PD5/T1 5

   ~ PD5/T1 5

   A2 PC1/ADC1

   A2 PC1/ADC1

   PD4/T0/XCK 4

   PD4/T0/XCK 4

   A3 PC2/ADC2

   A3 PC2/ADC2

   ~ PD3/INT1 3

   ~ PD3/INT1 3

   DIGITAL (~PWM)

   DIGITAL (~PWM)

   ANALOG IN

   ANALOG IN

   1121

   ATMEGA328P-PU

   1121

   ATMEGA328P-PU

   [1]	R. Saravanamoorthi, P. Rathinavel, E. Sandhya and K.M. Manu, Arduino Based Pwm Output Voltage Control of a DC-DC Boost Converter, International Journal of Engineering Research &
   	Technology (IJERT), Vol. 6 Issue 03, March-2017, pp. 348-350.
   [2]	C. Buccella, C. Cecati and H. Latafat, Digital Control of Power ConvertersA Survey, IEEE Transactions on Industrial Informatics, VOL. 8, NO. 3, August 2012, pp. 437-447.
   [3]	S.A. Lopa, S. Hossain, M. K. Hasan and T. K. Chakraborty, Design and Simulation of DC-DC Converters, International Research Journal of Engineering and Technology (IRJET), Vol. 03 Issue 01, Jan-2016, pp. 63-70.
   [4]	T. Bouguettaya and N. Obeidi, Commande dun Moteur à Courant Continu Alimenté par un Hacheur avec la Carte Arduino, Department of electrical engineering, El-Oued University, Algeria. Submitted for the requirements for the Degree of Master in Electric Control, May- 2016.
   [5]	[Online]. Available: https://www.f-legrand.fr/scidoc/index.html.
   [6]	M. H. Rashid and F. L. Luo, Power Electronics Handbook: Devices, Circuits and Applications, 2nd ed. New York: Elsevier Academic, 2006.

   [1]	R. Saravanamoorthi, P. Rathinavel, E. Sandhya and K.M. Manu, Arduino Based Pwm Output Voltage Control of a DC-DC Boost Converter, International Journal of Engineering Research &
   	Technology (IJERT), Vol. 6 Issue 03, March-2017, pp. 348-350.
   [2]	C. Buccella, C. Cecati and H. Latafat, Digital Control of Power ConvertersA Survey, IEEE Transactions on Industrial Informatics, VOL. 8, NO. 3, August 2012, pp. 437-447.
   [3]	S.A. Lopa, S. Hossain, M. K. Hasan and T. K. Chakraborty, Design and Simulation of DC-DC Converters, International Research Journal of Engineering and Technology (IRJET), Vol. 03 Issue 01, Jan-2016, pp. 63-70.
   [4]	T. Bouguettaya and N. Obeidi, Commande dun Moteur à Courant Continu Alimenté par un Hacheur avec la Carte Arduino, Department of electrical engineering, El-Oued University, Algeria. Submitted for the requirements for the Degree of Master in Electric Control, May- 2016.
   [5]	[Online]. Available: https://www.f-legrand.fr/scidoc/index.html.
   [6]	M. H. Rashid and F. L. Luo, Power Electronics Handbook: Devices, Circuits and Applications, 2nd ed. New York: Elsevier Academic, 2006.

   Fig.25: Proteus simulation of the buck-boost converter

   Fig.26: Proteus waveforms of the buck-boost converter

   The yellow waveform represents the inductor voltage and the red waveform represents the load voltage . Since the capacitor C has a finite value (C=54µF), the output voltage u is not constant (it has a ripple). Practical measurements confirm Proteus simulation as shown in Fig.27.

   Fig.27: Measured load and inductor voltages for buck-boost converter

5. CONCLUSION

In this project, a DC-DC converter bench is designed. This experimental bench is a multi-topology bench. It allows students to study the elementary DC-DC converters that are buck, boost and buck-boost converters. For this DC-DC converter, the pulse needed for switching semiconductor device is generated using the Arduino Uno.

Before performing experimental measurements, simulations with the Proteus software are carried out. The simulations results obtained are in accordance with measurements.

This project highlights that Arduino offers a simple and efficient way to control power converters.

REFERENCES