05-07-2013, 01:44 PM
A Project Report On GSM BASED INTELLIGENT CIRCUIT BREAKER
GSM BASED INTELLIGENT.pdf (Size: 1.9 MB / Downloads: 100)
ABSTRACT
The paper proposes a wireless solution based on GSM (Global System for
Mobile Communication) networks for the monitoring, diagnostic and control of the
medium voltage (MV) and high voltage (HV) circuit breakers. This architecture has
the advantage that can be used for the monitoring of some electrical and cinematic
parameters for the operating mechanism, the alarms being sent via GSM network.
Also, the proposed system allows on-line monitoring and diagnostic of the equipment.
INTRODUCTION
As the social economy is developing fast in 21st century, high speed, high
performance, and convenience have become a very common demand of people. So as
to existing wired communication technology can’t yet meet the need of getting
communication and information at anytime anywhere. However, the integration of
Internet and wireless communication technique make many applications change from
ideal into reality, such as remote monitor, diagnostic and control of different electrical
equipment and installations. In a word, more and more devices are required to own
the ability of wireless communication.
Modern control systems for industrial applications require automated data
reading on-line monitoring and batch command processing so remote access is an
important feature. One possible solution for remote access is GSM technology,
available almost everywhere and requiring no cabling; its costs are sinking now due
to struggle for market share between GSM operators, making it very attractive for a
large range of applications, GSM technology can be used for data transfers in two
different ways – circuit switching data transfers.
According to circuit in this project we are used sensors for sensing different
parameter in circuit sensors are placed on specific location in system, first we read
voltages of sensors which is connected to ADC pin of micro controller.
Microcontroller sends ADC reading to mobile and read the data & calibrate it, check
thresholds values of all sensors When it should be high then it break mains power
supply and sent the SMS to the define no. along with data recording
POWER SUPPLY:-
The ac voltage, typically 220V rms, is connected to a transformer, which steps
that ac voltage down to the level of the desired dc output. A diode rectifier then
provides a full-wave rectified voltage that is initially filtered by a simple capacitor
filter to produce a dc voltage. This resulting dc voltage usually has some ripple or ac
voltage variation.
A regulator circuit removes the ripples and also remains the same dc value even if the
input dc voltage varies, or the load connected to the output dc voltage changes. This
voltage regulation is usually obtained using one of the popular voltage regulator IC
units.
POTENTIAL TRANSFORMER:-
Potential transformers are instrument transformer .they has a large number of
primary turns and a few number of secondary turns. it is used to control the large
value of voltage. The potential transformer work along the same principle of other
transformer. It converts voltage from high to low. It will take the thousand of volts behind power transmission system and step the voltage down to something that meter
can handle. This transformer work on single and three phase system, and are attached
at point where it is convenient to measure the voltage.
CURRENT TRANSFORMER:-
A current transformer is used in high voltage circuits where it is not possible
to measure current directly. A CT is a step up transformer with only one turn in
primary. There will be as many cores based on the purposes like metering, protection
etc. The secondary of a CT should never be kept open circuited because very high
flux will be developed in the secondary and hence it may be damaged.
PRECISION RECTIFIER:-
Rectifier circuits are used in the design of power supply circuits. In such
applications, the voltage being rectified is usually much greater than the diode voltage
drop, rendering the exact value of the diode drop unimportant to the proper operation
of the rectifier. Other applications exist, however, where this is not the case. For
example, in instrumentation applications, the signal to be rectified can be of very
small amplitude, say 0.1 V, making it impossible to employ the conventional rectifier
circuits. Also the need arises for very precise transfer characteristics.
SHUNT RESISTOR:-
In its most basic principle, a current shunt is a very low value resistor that is
placed in the circuit so as not to cause any imbalance of the operation of that circuit;
then the voltage across the shunt resistor is used to determine the current flow using
ohm's law, I = V/R . For example, if the shunt resistance is only 0.01 ohm and a
current of 100 amps is flowing through it, the voltage drop would be 1 volt. If it were
a 120v circuit, the 1v would not be significant and the current measurement or
detection would be very precise. Most shunts are temperature compensated so that as
heat dissipation brings up temperature the voltages ensign mains accurate.
Shunts are used in a very broad application range from power to RF and to
microwave. There are many very sensitive meters that use shunt plug-in for a wide
range of current measurements. A shunt can also be used to trigger circuit protection
and power management systems
LIQUID CRYSTAL DISPLAY (LCD):-
Liquid crystal displays (LCDs) have materials, which combine the properties
of both liquids and crystals. Rather than having a melting point, they have a
temperature range within which the molecules are almost as mobile as they would be
in a liquid, but are grouped that the light rays come out of the LCD without any
orientation, and hence the LCD appears transparent. together in an ordered form
similar to a crystal.
An LCD consists of two glass panels, with the liquid crystal material sand
witched in between them. The inner surface of the glass plates are coated with
transparent electrodes which define the character, symbols or patterns to be displayed
polymeric layers are present in between the electrodes and the liquid crystal, which
makes the liquid crystal molecules to maintain a defined orientation angle. One each
polarizes are pasted outside the two glass panels. These polarizes would rotate the
light rays passing through them to a definite angle, in a particular direction. When the
LCD is in the off state, light rays are rotated by the two polarizes and the liquid
crystal.
RELAY:-
A relay is an electrically operated switch. Current flowing through the coil of
the relay creates a magnetic field which attracts a lever and changes the switch
contacts. The coil current can be on or off so relays have two switch positions and
they are double throw (changeover) switches. Relays allow one circuit to switch a
second circuit which can be completely separate from the first. For example a low
voltage battery circuit can use a relay to switch a 230V AC mains circuit. There is no
electrical connection inside the relay between the two circuits; the link is magnetic
and mechanical.
The coil of a relay passes a relatively large current, typically 30mA for a 12V relay,
but it can be as much as 100mA for relays designed to operate from lower voltages.
Most ICs (chips) cannot provide this current and a transistor is usually used to amplify
the small IC current to the larger value required for the relay coil. The maximum
output current for the popular 555 timer IC is 200mA so these devices can supply
relay coils directly without amplification.
CONCLUSION
Thus the automation of electrical circuit breaker is designed and implemented
using GSM technology. This brings out the efficient way of power transmission and
distribution in electrical substation though it is carried out using wireless mobile
communication technology.