The Development of Microcontroller-based Electrostatic Air Filter

Device using Flyback Transformer

Nasruddin M. Noer, Harris Fadhilla Said, Zikri Noer and Siti Utari Rahayu

Department of Physics, Faculty of Mathematics and Natural Sciences, University of Sumatera Utara, Medan 20155,

Sumatera Utara, Indonesia

Keywords: Air Filter Device, Electrostatic Method, ATmega328 Microcontroller, Flyback Transformer

Abstract:

This study aimed to develop a microcontroller-based air filter device using electrostatic method with high

voltage obtained from flyback transformer. The design of flyback transformer required several circuits, such

as ATmega 328 microcontroller, optocoupler, and driver, whereas the electrostatic method was applied by

arranging aluminum metal plates parallel with three anodes and cathodes. The results showed that the duty

cycles of 30%, 40%, 50%, 60%, and 70%, produced an output voltage of 2.632 kV, 7.250 kV, 13.16 kV,

20.01 kV and 27.55 kV, respectively, with the amount of dust particles as much as 0.2122 grams, 0.5147

grams, 0.8960 grams, 1.1620 grams and 1.9267 grams. These results suggest that higher the duty cycle

results in higher output voltage and larger amount of filtered dust.

1 INTRODUCTION

The development of research on high voltage is

rapidly increased; It requires a large and complicated

circuit. However, the research on the application of

high voltage is not only for industrial scale, but also

must be developed in all fields, especially in the

health sector (Barsoum, 2015). In the field of high

voltage health, it can be used as an air filter. Air is

an environmental medium that is a basic human

need, so it needs to get serious attention. Healthy air

at homes and offices is a necessity in the era of

modern society. We cannot deny that particulate air

in homes and offices can endanger human health

(Sudrajad A, 2019). Based on WHO data in 2012,

around 7 million people die each year from diseases

related to air pollution. In this case including heart

disease, stroke, lung and breathing, and cancer. On

the other hand, pollutants in the air not only

endanger health but also disrupt the climate such as

fine particle, black carbon, and surface ozone

)(Soemirat, 2014).

Dust particles are in the air for a relatively long

time in a state of floating and then entering the

human body through breathing so that it can

endanger health. Every material including dust can

be considered as an electrically charged particle that

will have the property of attraction with other

particles of different charge and repel with particles

that have the same charge (Gianto, 2015).

Regarding that, a study conducted by Raditya et al.

showed an air filter with a trade capacity of 8 kV

using the Walton Cockroft method electrostatically.

However, they could only precipitate dust of

0.001541 grams in 60 hours with an average of

0.000154 for six hours (Raditya, 2011). Therefore,

further study needs to be done on the development

of air filter device.

Based on those explanations, in this research,

an electrostatic air filter was developed using high

voltage obtained from flyback transformer. The air

filter is carried out using aluminum plates arranged

in a parallel order, by providing an electric field so

that dust particles in the air settle to the plates with

different charges. The system was controlled by

utilizing ATmega328 microcontroller.

2 METHODS

The method of conducting this research was carried

out in two stages, namely the design of a high

voltage device using the flyback transformer method

and an air filter device using the electrostatic

method.

438

Noer, N., Said, H., Noer, Z. and Rahayu, S.

The Development of Microcontroller-based Electrostatic Air Filter Device using Flyback Transformer.

DOI: 10.5220/0010200500002775

In Proceedings of the 1st International MIPAnet Conference on Science and Mathematics (IMC-SciMath 2019), pages 438-444

ISBN: 978-989-758-556-2

2.1 Design High Voltage Devices using

the Flyback Transformer Method

Flyback Transformer is a transformer with a ferrite

core that generates a high voltage on the cathode ray

(CRT) both on television and on the monitor. The

main function of this transformer is to trigger (fire)

electrons in a CRT tube. Flyback transformer has

several winding namely primary and secondary

winding. Secondary windings are wound in geater

amounts than primary winding with the aim of

different voltage levels so that they can bend and

accelerate the electron beam. Flyback transformers

are made of a coil with quality wire wrapped around

the ferrite core with air blemishes. This function is

to store energy in air blemishes and induce.

To get the output voltage in kilovolts, several

circuits are needed, namely the ATmega 328

Microcontroller, optocoupler, and driver. The

advantage of using the flyback method is that it can

produce high output voltages with low input

voltages. The process of the circuit can be seen in

Figure 1 below:

Figure 1: Block diagam

In the process a minimum voltage of 5 volts is

needed to activate ATgaga 328, to provide

regulating the duty cycle at the foot of the Atmega

328, the duty cycle setting uses a progam that is

entered through a computer to the Atmega 328, the

duty cycle can be adjusted using a potentiometer

which will then be displayed on the LCD. The

progam process of the Atmega series can be seen in

Figure 2 below:

Figure 2: Flowchart

In this circuit, all components must be in a high

voltage phase, so it is not damaged, such as the

optocoupler. The function of the optocoupler is to

deliver high voltage to the Insulated Gate Bipolar

Transistor (IGBT) driver, which will then be

transmitted to the flyback transformer leg. Then

from the flyback will come a high voltage in the

kilovolt scale, which is measured using a 40kV high

Lutron High Voltage Probe. The series of all the

tools can be seen in Figure 3 below:

Figure 3: Overall circuit

The Development of Microcontroller-based Electrostatic Air Filter Device using Flyback Transformer

439

30 40 50 60 70

Output Voltage (kV)

Duty Cycle (%)

2.2 Design the Air Filter using the

Electrostatic Method

The dust has to settle properties due to the earth's

gavity force. Also, the dust has static electricity

(electrostatic) properties that will be attracted to

particles opposite the charge and away from

similarly charged particles. The material that we

normally experience can be seen from a form of

three kinds of particles which have mass and particle

charge can be seen in Table 1 below:

Table 1: Mass and particle charge

Particles S

mbol Loa

Mass

(

Proton P +e 1.67 x 10

-27

Neutron N 0 1.67 x 10

-27

Electron E -e 9.10 x 10

-31

Electrostatic is the force that arises on two objects

that have static electricity, this is in accordance with

the sound of Colomb's law "The electric force

(attraction or repulsion) between two electric

charges is proportional to the amount of electric

charge each and is inversely proportional to the

square of the distance split between the two electric

charges. "

F = k













(1)

The design of the air filter referred to here is an

aluminum metal plate arranged parallel to three

anodes and three cathodes intermittent with a length

of 30 cm, width 20 cm and 0.8 mm thick, aligned

with a distance of 2.5 cm. This is done so that no

plasma discharge occurs when connected to a

flyback. The series of overall tools can be seen in

Figure 4 below:

Figure 4: Overall set of tools

3 RESULT AND DISCUSION

From a current of 220 ACV, the current is changed

to 12 DCV using a power supply and then converted

to 5 DCV using a Regulator IC, which will then be

connected to the Atmega 328. The Atmega 328

microcontroller circuit also obtained a frequency

that passes through the optocoupler that is equal to 3

kHz.

3.1 Measurement of High Voltage

using the Lutron 40kV HV Probe

With an input voltage of 12 volts on the flyback, an

output voltage using a 40kV Lutron HV probe is

obtained. The Lutron 40kV HV Probe readout used a

scale with a ratio of 1: 1000 on the multimeter

reading, the output voltage obtained from the

flyback at a duty cycle of 30%, 40%, 50%, 60%, and

70% can be seen in Table 2 below:

Table 2: Measurements with the 40kV Lutron HV Probe

Duty Cycle (%) Vout (kV)

30 % 2.632

40 % 7.250

50 % 13.16

60 % 20.01

70 % 27.55

From the data in table 2, can be illustrated graph

output voltage vs. duty cycle as in Figure 5 below:

Figure 5: Graph of output voltage vs duty cycle

Figure 5 shows that the higher the duty cycle, the

higher the output voltage. This is because the PWM

pulse width expressed in the duty cycle changes

linearly which causes the output voltage to change.

IMC-SciMath 2019 - The International MIPAnet Conference on Science and Mathematics (IMC-SciMath)

440

0,02

0,04

0,06

0,08

0,1

0,12

Dust Weight (grams)

Time (Hours)

3.2 Dust Weight with 2.632kV (30%

Duty Cycle)

Dust weight with a voltage of 2.632kV at a 30%

duty cycle. And obtained the weight of dust at each

time of data collection, in table 3 below:

Table 3:

Dust weight at any time at 2.632kV

Time (Hours) Dust Weight (g)