DESIGN AND IMPLEMENTATION OF SMART HOME CONTROL SYSTEMS USING POWER LINE COMMUNICATION

Sai Vishal1

,S.T. Aarthy2,Tungala Sai Puneeth

,Neelisetty Jagadeesh

4

1,2,3,4B.Tech, Electronics and Communication, University, Chennai, India

saipvishal@saimail.com, aarthy.s@ktr.srmuniv.ac.in, saipuneeth369@gmail.com, jagadeesh.neeeliseety@gmail.com

SRM

Abstract: A smart home network uses a multitude

of sensors and and all of them have to be

connected to each other. Each set of sensors in a

particular room is considered as a node. In

traditional smart homes wireless sensor networks

(WSN) are used. WSNs have a number of

problems. Here we hope to over to overcome them

using PLC. The sensors in the PLC based smart

home network are connected using the electrical

wiring running through the house. These cables

have a phase and a neutral. The phase which is

used to transmit electricity is also used to transmit

the signals from the sensors. The sensors are

connected to a PIC microcontroller which is then

connected to a PLC modem. The PLC modem then

either modulates or demodulates the signal from or

to the PIC microcontroller in any of the nodes. The

readings of each node can be read from the PIC

microcontroller in the same node. In addition to

this all the readings from all the nodes can be read

on the PC. The modulation technique used in the

PLC modem is Orthogonal Frequency Division

Multiplexing (OFDM).

Keywords: power line communication, smart

homes, orthogonal frequency division multiplexing

1. Introduction

Every device in today's world is going smart,

starting from mobile phones to TV's and even

refrigerators and homes. Smart homes are still very

uncommon but this will change in the coming

years. A smart homes consists of multiple sensors

and devices operating together to make the user as

comfortable as possible.

Most of the existing and even proposed

architectures of smart homes use wireless sensor

networks (WSN)[1] .But wireless systems have

multiple problems like range, interference, packet

loss, scalability, etc., so they are not very efficient.

These problems can be overcome by using wired

solutions but, the reason we even use wireless

solutions is that wires are incredibly messy and

whatever you do to cover all the wires is time

consuming, difficult and we might even end up

drilling holes in our walls.

An efficient and elegant solution is either a

wireless system which does not succumb to the

problems given above or a non messy wired

system. In this work the latter is used. The

question now is how to arrange a non messy wired

system that also does not need an excessive

amount of time to arrange.

The answer is to use existing wiring in the house.

By using the existing wiring there is no mess

created compared to using new wiring. The cost is

also kept pretty low. But how do you transmit and

receive signals from and to the nodes, each of

which is placed in a different room.

There is a technology called power line

communication (PLC) or power line carrier

communication (PLCC)[1]. PLC allows us to send

information through the electrical wiring. This

technology has been in wide use since 1950 and

was mainly used by the grid stations to transmit

information at high speed.

The information from the node is sent to a PLC

modem. The modem then modulates the signal and

sends it through the phase of the electrical wiring.

PLC modems are connected to every node. So,

every PLC modem can send and receive

information from every other modem. A PC or

laptop is connected to any of the nodes and it

receives information from all the nodes.

The modem that we are using is KQ330, but other

modems can also be used. The KQ330 modem

uses Orthogonal Frequency Division Multiplexing

(OFDM) [2].

International Journal of Pure and Applied MathematicsVolume 115 No. 7 2017, 577-583ISSN: 1311-8080 (printed version); ISSN: 1314-3395 (on-line version)url: http://www.ijpam.euSpecial Issue ijpam.eu

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2. Methodology

A smart home requires multiple components to

automate various things which would otherwise

require manual operation.

Given below is a block diagram of the prototype of

the proposed system:

Figure. 1. Block diagram

a) PLC Modem The device used to send and receive information

through the wiring is called the PLC modem. The

modem that we use is the KQ330[3]. It is one of the

components connected to the power supply.

Therefore, the input of the modem is 230V AC. The

modem modulates the information sent from and to

the PIC microcontroller. By using modulation

techniques, binary data stream is keyed on to a

carrier signal and then coupled on to the power lines

by the modem. At the receiver end another modem

detects the signal and extracts the corresponding bit

stream. Data is processed before transmission on

power lines. First data is modulated and filtered and

then by using couplers, it is sent over the power

lines.

A smart home requires multiple components to

automate various things which would otherwise

Given below is a block diagram of the prototype of

The device used to send and receive information

through the wiring is called the PLC modem. The

modem that we use is the KQ330[3]. It is one of the

components connected to the power supply.

Therefore, the input of the modem is 230V AC. The

ulates the information sent from and to

the PIC microcontroller. By using modulation

techniques, binary data stream is keyed on to a

carrier signal and then coupled on to the power lines

by the modem. At the receiver end another modem

d extracts the corresponding bit

stream. Data is processed before transmission on

power lines. First data is modulated and filtered and

then by using couplers, it is sent over the power

Figure. 2. KQ330 PLC modem module

The modulation technique used by the KQ330 is

Orthogonal Frequency Division Multiplexing

(OFDM) [2]. b) Why OFDM? The characteristics of the power line channel

continuously vary with time and load. So

conventional modulation tech

FSK or PSK cannot be employed

needs a technique that can deal with unpredictable

Attenuation and phase shifts.

Modulation techniques that can opt lower frequency

ranges of 35KHz to 95KHz can perform better as

compared to the whole available frequency band.

OFDM [2] is the modulation technique that is used

in home plug specification network appliances. In

OFDM, information is modulated on to a multiple

carrier, where each carrier occupies its own

frequency ranging from 4.3 to 20.9MHz. Incoming

bit stream is demultiplexed

parallel bit streams each with 1/N of original bit rate

which are modulated then on N orthogonal carriers.

By using multiple carriers at a time, the OFDM uses

the spectrum most efficiently. During the

transmission, each frequency is monito

any interferences, noise or data loss occurs, the

responsible frequency is ignored. However, this

OFDM does not perform well when a large

attenuation and jamming occurs in the

communication channel, yet it can perform effectively when compared to other modulation

techniques.

c) PIC Microcontroller

The microcontroller is quite literally the brains of

each node. In our prototype, PIC microcontroller,

specifically the PIC16F877A is used. The

PIC16F877A features 256 bytes of EEPROM data

memory, self-programming, an ICD, 2 Comparators,

8 channels of 10-bit Analog

converter, 2 capture/compare/PWM functions, the

synchronous serial port can be configured as either 3

wire Serial Peripheral Interface (SPI) or the 2

Inter-Integrated Circuit (I²C) bus and a Universal

Asynchronous Receiver Transmitter (USART). All of

these features make it ideal for more advanced level

A/D applications in

KQ330 PLC modem module

used by the KQ330 is

Orthogonal Frequency Division Multiplexing

The characteristics of the power line channel

continuously vary with time and load. So

conventional modulation tech-niques like ASK,

FSK or PSK cannot be employed with them. PLCC

needs a technique that can deal with unpredictable

Modulation techniques that can opt lower frequency

ranges of 35KHz to 95KHz can perform better as

compared to the whole available frequency band.

he modulation technique that is used

in home plug specification network appliances. In

OFDM, information is modulated on to a multiple

carrier, where each carrier occupies its own

frequency ranging from 4.3 to 20.9MHz. Incoming

bit stream is demultiplexed into N number of

parallel bit streams each with 1/N of original bit rate

which are modulated then on N orthogonal carriers.

By using multiple carriers at a time, the OFDM uses

the spectrum most efficiently. During the

transmission, each frequency is monitored and if

any interferences, noise or data loss occurs, the

responsible frequency is ignored. However, this

OFDM does not perform well when a large

attenuation and jamming occurs in the

communication channel, yet it can perform

to other modulation

The microcontroller is quite literally the brains of

each node. In our prototype, PIC microcontroller,

specifically the PIC16F877A is used. The

PIC16F877A features 256 bytes of EEPROM data

programming, an ICD, 2 Comparators,

bit Analog-to-Digital (A/D)

converter, 2 capture/compare/PWM functions, the

synchronous serial port can be configured as either 3-

wire Serial Peripheral Interface (SPI) or the 2-wire

Circuit (I²C) bus and a Universal

Transmitter (USART). All of

these features make it ideal for more advanced level

International Journal of Pure and Applied Mathematics Special Issue

578

automotive, industrial, appliances and consumer

applications.

Figure. 3.PIC16F877A

d) Temperature sensor The temperature sensor used is LM35. It is an IC

sensor that can be used to measure temperature (in oC) with an output voltage proportional to it.

Figure. 4. Temperature sensorLM35 The scale factor is .01V/

oC. It does not require any

external calibration or trimming and maintains an

accuracy of +/-0.4 oC at room temperature and +/

0.8 oC over a range of 0

oC to +100

important characteristic of the LM35DZ is that it

draws only 60 micro amps from its supply and

possesses a low self-heating capability. The output

voltage is converted to temperature by a simple

conversion factor. The sensitivity of the sensor is

10mV / oC. We use a conversion factor that is the

reciprocal, that is 100

oC/V. To output voltage to temperature we

use the following equation:

automotive, industrial, appliances and consumer

The temperature sensor used is LM35. It is an IC

sensor that can be used to measure temperature (in

C) with an output voltage proportional to it.

C. It does not require any

external calibration or trimming and maintains an

C at room temperature and +/-

C to +100 oC. Another

important characteristic of the LM35DZ is that it

from its supply and

heating capability. The output

voltage is converted to temperature by a simple

conversion factor. The sensitivity of the sensor is

C. We use a conversion factor that is the

utput voltage to temperature we

Temperature ( oC) = Vout * (100

So if Vout is 1V , then, Temperature = 100 The output voltage varies linearly with

temperature.

e) Humidity Sensor

Humidity Sensor is used to determine

humidity of the surrounding area. Humidity is the

amount of water vapor in the air. Humidity

indicates the probability of precipitation, dew or

fog. Higher humidity reduces the effectiveness of

sweating in cooling the body by reducing the rate

of evaporation of moisture from the skin.

Humidity is calculated in a heat index table or

humidex. The humidity sensor that is used here is

DHT11. It measures the realtive humidity which

is the current absolute humidity relative to the

maximum for that temperature

percentage.

Figure. 5. Humidity Sensor

f) Gas Sensor

A gas sensor is used to detect the presence of gas in

an area. It is used as a part of safety systems to

detect gas leaks. Here we use an MQ6

electrochemical gas sensor. It has high sensitivity to

LPG, iso-butane, propane and low sensitivity to

smoke and alcohol. It works by allowing gases to

diffuse through a porous membrane to an electrode

where it is either chemically oxidized or reduced.

The amount of current produced is determined by

how much of the gas is oxidized at

indicating the concentration of the gas. We use

electrochemical sensors because they are small and

they tended to be more stable and reliable over the

sensor's duration since the diffusion barrier is a

physical/mechanical barrier. Manufactures can also

customize electrochemical gas sensors by changing

the porous barrier to allow for the detection of a

certain gas concentration range.

C) = Vout * (100 oC/V)

So if Vout is 1V , then, Temperature = 100 oC

The output voltage varies linearly with

Humidity Sensor is used to determine the

humidity of the surrounding area. Humidity is the

amount of water vapor in the air. Humidity

indicates the probability of precipitation, dew or

fog. Higher humidity reduces the effectiveness of

sweating in cooling the body by reducing the rate

ration of moisture from the skin.

Humidity is calculated in a heat index table or

humidex. The humidity sensor that is used here is

DHT11. It measures the realtive humidity which

is the current absolute humidity relative to the

maximum for that temperature and is expressed in

. Humidity Sensor

A gas sensor is used to detect the presence of gas in

an area. It is used as a part of safety systems to

detect gas leaks. Here we use an MQ6

electrochemical gas sensor. It has high sensitivity to

butane, propane and low sensitivity to

lcohol. It works by allowing gases to

diffuse through a porous membrane to an electrode

where it is either chemically oxidized or reduced.

The amount of current produced is determined by

how much of the gas is oxidized at the electrode

ntration of the gas. We use

electrochemical sensors because they are small and

they tended to be more stable and reliable over the

sensor's duration since the diffusion barrier is a

physical/mechanical barrier. Manufactures can also

al gas sensors by changing

the porous barrier to allow for the detection of a

certain gas concentration range.

International Journal of Pure and Applied Mathematics Special Issue

579

Figure.6.Gas Sensor

g) LDR A Light Dependent Resistor (aka LDR,

photoconductor, or photocell) is a light controlled

variable resistor. It has a resistance that varies

according to the amount of light falling on its

surface. It exhibits photoconductivity which means

that its resistance decreases with increasing intensity

of incident light. Light dependent resistors are a

vital component in any electric circuit which is to be

turned on and off automatically according to the

level of ambient light. Figure.7.LDR h)LCD LCD (Liquid Crystal Display) a flat panel display

module. A 16x2 LCD display is very basic module

and is very commonly used in various devices and

circuits. LCD's are preferred over seven segments

and other multi segment LED's. The reasons being:

LCD's are economical; easily programmable; have

no limitation of displaying special & even custom

characters (unlike in seven segments), animations

and so on. A 16x2 LCD can display 2 lines, each consisting

of16 characters. In this LCD each character is

displayed in 5x7 pixel matrix. This LCD has two

registers, namely, Command and Data.

The command register stores the command

instructions given to the LCD while the data

register stores the data to be displayed on the

LCD.

Light Dependent Resistor (aka LDR,

photoconductor, or photocell) is a light controlled

resistor. It has a resistance that varies

according to the amount of light falling on its

surface. It exhibits photoconductivity which means

that its resistance decreases with increasing intensity

of incident light. Light dependent resistors are a

mponent in any electric circuit which is to be

turned on and off automatically according to the

LCD (Liquid Crystal Display) a flat panel display

module. A 16x2 LCD display is very basic module

is very commonly used in various devices and

circuits. LCD's are preferred over seven segments

and other multi segment LED's. The reasons being:

LCD's are economical; easily programmable; have

no limitation of displaying special & even custom

unlike in seven segments), animations

A 16x2 LCD can display 2 lines, each consisting

of16 characters. In this LCD each character is

displayed in 5x7 pixel matrix. This LCD has two

s the command

instructions given to the LCD while the data

register stores the data to be displayed on the

A command is an instruction given to LCD to do

a predefined task like initializing it, clearing its

screen, setting the cursor position, contro

display etc. whereas the data comprises of the

ASCII value of the character to be displayed on

the LCD.

Figure .8. LCD i) Relay A relay is an electro-mechanical switch that is

capable of being remotely actuated/controlled.

The schematics involving relays could be very

simple, or incredibly complex since they may

employ the well-known "relay A relay contains two parts: a switch (or a system

of switches) that controls the

power/primary/analog circuits, and a digital

(remote) control part. Figure .9. Relay

j) DC Motor

A DC motor runs on DC electric power. It works on

the principal that when a current carrying conductor

is placed in Magnetic field, it experiences a torque

and has a tendency to move. This is known

motoring action. If the direction of current in the

wire is reversed, the direction of rotation also

reverses. The working principle of the DC motor is

based on

the fact that the interaction between magnetic field

and electric field produces a mechanica

A command is an instruction given to LCD to do

a predefined task like initializing it, clearing its

screen, setting the cursor position, controlling

display etc. whereas the data comprises of the

ASCII value of the character to be displayed on

mechanical switch that is

capable of being remotely actuated/controlled.

schematics involving relays could be very

simple, or incredibly complex since they may

known "relay-logic".

A relay contains two parts: a switch (or a system

of switches) that controls the

power/primary/analog circuits, and a digital

A DC motor runs on DC electric power. It works on

the principal that when a current carrying conductor

is placed in Magnetic field, it experiences a torque

and has a tendency to move. This is known as

motoring action. If the direction of current in the

wire is reversed, the direction of rotation also

reverses. The working principle of the DC motor is

the fact that the interaction between magnetic field

and electric field produces a mechanical force.

International Journal of Pure and Applied Mathematics Special Issue

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.

Figure .9.DC Motor

k) Cooling and Exhaust Fans These are basically small PC fans to stimulate the

blower of an air conditioner and the exhaust of a

kitchen. Figure .11. Cooling and Exhaust Fans

l) Bulb The bulb or a tube switches on and off depending

on the LDR value. Any bulb can be used since it is

connected to the full 230V AC power supply

Figure .12. Bulb

3. Implementation of the

Proposed system The result of the implementation is the successful

transfer of information between the nodes and to

view all the information on the PC or laptop. Figure .13.Hardware Setup In node 1, the 230V AC power supply is

connected to the PLC modem and a 12V step

down transformer. The 12V transformer is

connected to the PIC microcontroller which is in

turn connected to the Temperature Sensor,

Humidity Sensor, PLC modem and the relay. Node 2 has a similar setup with some differences.

The 230V AC power supply is also connected to a

bulb in addition to the modem and transformer.

LDR and Gas Sensor are used here and the relay

switches on the bulb and exhaust fan in response

to crossing the threshold value corresponding to

them respectively.

The information regarding the nodes can be viewed

in the LCD display of the PIC microcontroller or on

the laptop

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Figure .14.Monitoring using PC

4. Real time smart home Architecture Smart home architecture using PLC would look like

the figure given below: Figure .15. Proposed Smart Home Architecture There are multiple sensor nodes in each room

connected to a PIC microcontroller. It is coded

using MPLAB to fit the necessary requirements of

the room. The PIC is then

connected to the PLC modem which is connected to

the electrical wiring running throughout the house.

The power line would then go to the PLC gateway

where it would connect to the computer. This is

where this system differs from most existing

systems where PIC is connected to wi-fi or ZigBee

which connect wirelessly to the computer and are

affected by problems like low range, packet loss

and interference with other wireless systems,

especially those operating in the 2,4 Ghz range like

WLAN, microwave oven etc. Additional features can also be added to the

proposed system like IOT through which you can

control your home system from any part of the

globe.

5. Conclusion

This work has involved designing a complete PLC

based smart home architecture. This proposed

system was developed by keeping in mind problems

facing WSNs. Here PLC is used both as the

backbone and for data sensing. We have developed

a prototype of the proposed system. It mitigates the

problem of wireless interference and packet loss, all

while increasing the range and scalability and even

reducing power loss. Using PLC based systems also

reduces the cost substantially and increases

efficiency.

References

[1] Ming Fu Li and Hung-Ju Lin “Design and

Implementation of Smart Home Control Systems

Based on Wireless Sensor Networks and Power

Line Communications”, IEEE Transactions on

Industrial Electronics Volume 62 Issue

7,December 2014.

[2] Nisha S Police Patil, Abhilasha P, Narendra

Kumar, “RF Based Data Communication Between

Industrial PLC’S USING KQ330 Module”,

International Journal of Industrial Electronics and

Electrical Engineering, Special Issue September

2016.

[3] Yin QUN, Zhang JIANBO, “Design of Power

Line Carrier Communication Systembased on

FSK-KQ330 Module” ELECTROTEHNICA

ELECTRONICA, AUTOMATICA.

vol.62(2014), Nr.3.

[4] V Padmajothi, Ankit Rai, M Dastagiri Reddy,

N Renu Kumar, “Cost Effective Home Energy

Monitoring System” International Innovative

Research Journal of Engineering and

Technology. Vol. 2, March 2017.

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