monitoring substation (distribution transformer) using ZIGBEE communication

1. SHARAD INSTITUTE OF TECHNOLOGY COLLEGE OF
ENGINEERING, YADRAV
A
PRESENTATION
ON
“MONITORING OF SUBSTATIONS USING
MICROCONTROLLER ”
PRESENTED BY
Mr. Mohsin I. Sutar
Mr. V. V Khandare
UNDER THE GUIDANCE OF
DEPARTMENT OF ELECTRONICS AND TELE-COMMUNICATION ENGG.

2. INTRODUCTION
 Main station transformers convert the generator's voltage to
extremely high voltages (155kV to 765 kV).
 Then, the voltage level is reduced using transformers and
power is transferred to customers through electric power
distribution systems (transformer)(typically to less than 10kV).
 Distributed transformers are prone to damages due to the
raise in oil temperature when there is an overload or huge
current flows through the internal winding of the transformer.
 We are going to designed a system based on microcontroller
(AVR) that monitors and controls the voltage, current and oil
temperature of a distribution transformer present in a
substation. The monitored output will be displayed on a LCD
at the main station that is at a remote place, through ZIGBEE
communication.

3. OBJECTIVE
The purpose of this project is to monitor
the remote electrical parameters like voltage,
current and temperature of a distribution
transformer of substation and send these real
time values over ZIGBEE communication to the
main station.

4. ABSTRACT OF THE PROJECT
 A system based on AVR micro controller that is used for monitoring
the voltage, current and temperature of a distribution transformer in a
substation and to protect the system from the rise in mentioned
parameters.
 Providing the protection to the distribution transformer can be
accomplished by shutting down the entire unit with the aid of the
ZIGBEE Communication.
 Furthermore it is capable of recognizing the break downs caused
due to overload, high temperature and over voltage.
 The design generally consists of two units, one in the substation
unit, called as transmitter and display unit, and another in the Main
station called as controlling unit.

5.  The transmitter and the display units in the substation is where the
voltage, current and temperature are monitored continuously by
AVR microcontroller and is displayed through the display unit.
 An ZIGBEE transmitter is used for transmitting the signals that are
obtained. The controlling unit in the main station by means of a
AVR MC and a ZIGBEE receiver receives the signals that are
transmitted by the Transmitter unit and reacts in accordance to the
received signal.
 The ultimate objective is to monitor the electrical parameters
continuously and hence to guard the burning of distribution
transformer or power transformer due to the constraints such as
overload, over temperature and input high voltage. If any of these
values increases beyond the limit then the entire unit is shut down
by the designed controlling unit

6. PROJECT OVERVIEW
 Monitoring of substations are essential task for supplying
healthy power to the consumers , there are transmission or
distribution substations those supply electrical power to various
loads. Remote monitoring make these substations to be
operated through wireless communication technologies like
ZIGBEE,..etc
 Substations consist of various equipment like transformers,
circuit breakers, relays etc,…. And these equipments ought to
be operated in such that the loads must be delivered safely
with specified parameters. These parameters include voltage,
current, temperature. The following ZIGBEE based project deal
with substation monitoring aspects

7. WORKING PRINCIPLE
The substation contains ZIGBEE transmitter and AVR
microcontroller. The main station consists of AVR Microcontroller,
ZIGBEE receiver and LCD display. The parameters (current, voltage,
oil temperature) of the substation is continuously acquired by the
AVR Microcontroller and transmits through the ZIGBEE transmitter
to the main station. The ZIGBEE receiver in the main station
receives the signal and compares it to the reference rated
measurements . If the received information is below the reference
rated measurements it does not shows any variation or if it is above
the reference rated measurements then that increased range is
viewed by LCD and indicated using LED and further damage can be
avoided by shutting down the substation using relay from the main
station.

8. BLOCK DIAGRAM

9. DESIGN PROCEDURES
 Define the interfacing parameters for LCD and Data
Registers.
 Assign a value for the circuit elements such as Relay,
LED.
 Initialize the input and output ports of the
microcontroller. The displaying function is called and
the parameter values are displayed.
 The captured values are transmitted by calling
ZIGBEE transmitter function

10. EQUIPMENTS USED
 ZIGBEE:
ZIGBEE is based on an IEEE 802.15.4 personal area network. The
technology defined by the ZIGBEE specification is intended to be
simpler and less expensive than other WPANs, such as Bluetooth.
ZIGBEE is targeted at Radio Frequency (RF) applications that require
a low data rate, long battery life, and secure networking. ZIGBEE
has a defined rate of 250 kbps.
In substation unit the power is continuously monitored and it is
transmitted through ZIGBEE transmitter and the transmitted signal
is received by ZIGBEE receiver.

11. Fig- Zigbee module
Performance
RF Data Rate 250 kbps
Indoor/Urban
Range
133 ft (40 m)
Outdoor/RF Line-of-
Sight Range
400 ft (120 m)
Transmit Power 1.25 mW (+1 dBm)
/ 2 mW (+3 dBm)
boost mode
Receiver Sensitivity
(1% PER)
-97 dBm (-98 dBm
boost mode)

12. AVR MICROCONTROLLER
• Features :-
 High-performance, Low-power, 8-bit Microcontroller
 Advanced RISC Architecture
 118 Powerful Instructions – Most Single-clock Cycle
 Execution – 32 × 8 General Purpose Working
Registers
 Fully Static Operation
 Up to 8MIPS Throughput at 8MHz – On-chip 2-cycle
Multiplier

13. AVR MICROCONTROLLER PINOUT

14. RELAY
 Number of poles 1 pole
 Contact resistance 100 mΩ
 max. Operate (set) time: 15 ms
 max. Release (reset) time: 5 ms max.
 Max. operating frequency Electrical:1,800
operation/hr at rated load
 Dielectric strength: 5,000 VAC, 1 min
between coil and contacts
 Endurance (Mechanical) 20,000,000
operations (at 18,000 operations/hr)
 Ambient humidity 5% to 85%
 Weight Approx. 12 g

15. LCD DISPLAY
•
Pin No Function Name
1 Ground (0V) Ground
2 Supply voltage; 5V (4.7V – 5.3V) Vcc
3 Contrast adjustment; through a variable
resistor
VEE
4 Selects command register when low; and
data register when high
Register Select
5 Low to write to the register; High to read
from the register
Read/Write
6 Sends data to data pins when a high to low
pulse is given
Enable
7 8-Bit data pins DB0
8 DB1
9 DB2
10 DB3
11 DB4
12 DB5
13 DB6
14 DB7
15 Backlight VCC (5V) Led+
16 Backlight Ground (0V) Led+

16. ADVANTAGES:-
 Remote monitoring to avoid further power
loss and time.
 Whole system can be shut down for quick
repairs and re-installations.
 Low maintenance .
 Fair efficiency.
 High accuracy.

17. DISADVANTAGES
Bulky circuit construction.
Costly.
Less operating area.

18. FUTURE SCOPE & PLAN
 This project can be implemented by using GPRS
technology so that captured data can be send anywhere
in the world.
 We can turn it to a “Smart Energy Meter” by which
electricity parameters along with cost calculation can be
monitored by the user by GSM or GPRS so they can
minimize their electricity uses to optimum level.

19. CONCLUSION
In this project we have presented a design of a system based
on AVR microcontroller that is used to monitor and control
the voltage, current and temperature of a distribution
transformer by shutting it down.
This claims that the proposed design of the system makes
the distribution transformer more robust against some key
power quality issues which makes the voltage, current or
temperature to peak. Hence the distribution is made more
secure, reliable and efficient by means of the proposed
system.

20. REFERENCE
 An efficient monitoring of substations using microcontroller
based monitoring system, IEEE Paper proposed by
Mr. V. Thiyagrajan on July 2010.
 Wikipedia