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1 MICROCONTROLLER BASED TRANSFORMER PARAMETER MONITORING WITH SMART CARD ACCESS N.H.MATE*1, N.D.PERANE*2, *1(Department of Electrical Engg.S.N.D.COE&RC Nasik, Maharashtra, India) *2(Department of Electrical Engg, S.N.D.COE&RC Nasik, Maharashtra, India) Abstract: In this paper, the objective is to monitor the robots. In order to help the tedious work and to reduce the efforts against manpower there is a transformer parameter such as general tendency to invent an intelligent or smart voltage,current,temperature using microcontroller with smart card access. This paper prescribe about the transformer which is used to energies the machines where the incoming supply voltage and the rated voltage of the distribution system are different. The transformer windings and insulation may get damage due the abnormal increase in a temperature and severity of occurrence of fault. In many cases transformer may get burst. It explain how to monitor the above parameter and isolate the power supply during emergencies. The output voltage and current measure with the help of potential and current operation. In our paper the each transformer is designed with the microcontroller based kit and also with this a smart card is provided for monitoring and conditioning purpose. When monitored parameter by microcontroller are transmitted via RS232 to PC if that values are within permissible limit then the transformer continues with it s the normal functions. But when monitored values are exceeds the predefined values measures will be taken to ensure the normal functioning of transformer. Under the high abnormal condition the transformer will be isolated. transformerrespectively, similarly temperature II.EXISTING SYSTEM sensor is used to monitor the temperature of the transformer. The monitored parameter will be send to PC via microcontroller and the corrective action At present the wired logic based PLC Kits are used for the monitoring purpose.this kits have the fixed output and input no. of ports and also they are costly. is taken by the operator if some parameter exceeds the predefine values. during severe fault condition the relay is operated and the supply to the transformer is isolated. Keywords:Transformer,Microcontroller,Voltage,Ele ctricity,current,temperature and Smart Card I. INTRODUCTION Now a days the industries would like to shift towards automations. Namely two components of the today s automations are programmable controllers and While connecting many devices it proves to be difficult as it is used by star topology. III.PROPOSED SYSTEM In this paper we implemented the microcontroller and smart card for data processing, transmission and monitoring purpose. Microcontroller allows us to use the multi ported pin and smart card is used to ensure that whether the dispatchers are on line or not. Smart cards are portable data card that must communicate with another device to gain access to a display device or network 1

2 . A. Block Diagram IV.LIQUID CRYSTAL DISPLAY Liquid crystaldisplays ((LCDs) are used in a PC RS 232 Microcontroller application where LEDs are used. These application displays the numeric and alphanumeric characters in a dot matrix and segment displays. Fig.1 Block Diagram OfPC Side In this side the transformer side parameter such as voltage, current, temperature values are obtained from the microprocessor and displayed.loading and tripping of transformer in case of abnormal conditions is also done from this section.microcontroller continuously monitor the parameter and simultaneously send this signals to the PC where the operator can take corrective action. LCDs are of two types I. Dynamic scattering type II. Field effect type Dynamic Scattering Type The liquid crystal material made from the several components generally which exhibits the optical properties of the crystal though they remain in a liquid form. Liquid crystal is sandwich between glass sheet with transparent electrode deposited in inner surfaces. When potential difference is applied between the faces electrons flowing through the liquid disrupt the molecular alignment and turbulence is produce. when liquid is not activated, it remain transparent. When liquid is activated the molecular turbulence causes light spread in all directions and cell appears to be bright.this is known as the dyanamic scattering. Field effect type It is similar in construction of the dynamic scattering type only difference is that two thin polarizing optical filters are placed at the inside. Fig.2 Transformer Side Block Diagram 2

3 Fig.3 LCD Interfacing With Microcontroller The LCDs are extensively used in a watches, calculators and in a measuring instruments. The recent advances in technology proves beneficial in better legibility, wider temperature range and capacity to show the more data. Hence these are being extensively used in a telecommunication and entertainment electronics. V. SENSORS: VOLTAGE TRANSFORMER Voltage transformers are generally recognize as Potential transformer (PT s) are design to know the accurately transformation ratio in magnitude and phase. They are used to supply electricity in industry to measure accurately the voltage being supplied. They are design to present negligible load to the voltage being measured. Also used to sense the over voltage and under voltage ratings of power transformer. Fig.4 Voltage Transformer CURRENT TRANSFORMER In an electrical engineering the current transformer is used to measure the electrical current. A current transformer is design to provide a current in its secondary which is accurately proportional to current flowing in its primary. A current transformer isolates the measuring instrument which are at high voltage in a monitoring circuit Current transformer are commonly used in electricity meters to facilitate the measurement of large current which would be difficult to measure more directly. Fig.5 Current Transformer 3

4 LM35 TEMPERATURE SENSOR We can measure temperature more accurately by using LM-35 sensor than the thermostat. The LM-35 series are precision integrated circuit temperature sensors whose output is linearly proportional to the Celsius temperature. It has advantage over linear temperature sensors calibrated in Kelvin, as user is not required to subtract a large constant voltage from its output to obtain convenient centigrade scaling. LM35 does not required any external calibration or trimming to provide typical accuracies of ±1/4 C at room temperature and ±3/4 C over a full -55 to +150 C temperature range. The LM35 comes in many packages including following. TO-92 plastic transistor-like package TO-202 package TO-46 metal can transistor packages 8 lead surface mount SO-8 small outline package VI.MICROCONTROLLER Microcontroller AT89S52 The AT89S52 is a low-power high performance CMOS 8-bit microcontroller with 8K bytes of in system programmable flash memory. The device is manufactured using Atmel s high density nonvolatile memory technology and is compatible with industry slandered 80C51 instruction set and pin out. MICROCONTROLLER FEATURES 8K Bytes of In- System programmable flash memory Endurance : 1000Write/Erase Cycles Fully static operation :0Hz to 33 MHz 256 x 8-bit Internal RAM Three-Level Program Memory Lock 32 Programmable I/O Lines Interrupt Recovery from Power-down Mode Full Duplex UART Serial Channel Low-power Idle and Power-down Modes Watchdog Timer PIN CONFIGURATION Fig.6 Connection OfLM35 With Microcontroller Fig.7 Microcontroller 89S52 Pin Configuration APPLICATIONS Microcontrollers are design for use in sophisticated real time application such as 4

5 Industrial control Instrumentation and intelligent computer peripherals They are also used in industrial application to control Motor, robotics, Discrete and continuous process control In missile guidance and control In medical instrumentation Oscilloscope VII.SMART CARD The smart card is one of the latest additions to the world of information technology. Similar in size to today s plastic payment card, the smart card has a microprocessor or memory chip embedded in it that, when couple with reader, has the processing power to serve many different applications. As an access-control device,smart cards make personal and business data available only to the appropriate users. Another application provides users with the ability to make a purchase or exchange value. Smart cards provide data portability, security and convenience. TECHNICAL OVERVIEW A smart card, chip card or integrated circuit card(icc) is any pocket sized card with embedded integrated circuits. They are made of plastic, generallypolyvinyl chloride but sometimes polyethylene terephthalate based polyesters, acronitrile butadiene styrene or polycarbonate. Itprovide identification,authentification data storage application processing. Smart card may provide strong security authentification for single sign-on (SSO) within large organization. smart card have two different types of interfaces: contact contactless Contact smart cards are inserted in to a smart card reader, making physical contact with the reader. However, contactless smart cards have an antenna embedded inside the card that enables communication with the reader without physical contact. A combo card combines the two features with a very high level security. SMART CARD INTERNAL ARCHITECTUREIn general smart cards conform to a standard architecture. The key element in proposed architecture is a microcontroller ROM,RAM,EEPROM and infrared communication interface. Fig.8 Smart Card Internal Architecture The reader provides a path for your application to send and receive commands from the card. There are many types of readers available, such as serial,pc card, and standard keyboard models. Each manufacturer provides a different protocol for communication with the reader in this paper the 5

6 contact type of smart card is used. There are smart card readers for inserting card in it. If any fault occurs in transformer, indicate on PC First you have to communicate with the reader. Second, the reader communicates with the card, acting as the intermediary before sending the data to card. Third, communication with smart card is based on APDU format. The card will process the data and return it to the reader, which will then return the data to its original source. VIII CONTROLLING EQUIPMENTS RELAY DRIVER. Fig. 8 Relay Driver Circuit Relays are electrically controlled switches. In usual type a coil pulls in an armature when sufficient coil current to be flows. There are many variables are available consisting stepping and latching relays; the later provided the comer stone for telephonic switching stations, still they are popular in a pin ball machine relays are available for dc and ac excitation and the voltage of coil from 5Volts up to 110 Volts are common mercury wetted intended for the high speed applications and giant relays intended to switch thousands of amps are used by power companies. Many previous relay applications can be handled with transistor or FET switches, and devices known as solid-state relays are now available to handle ac switching applications. The primary uses of relays are in remote switching and high-voltage switching because it is important to keep electronic circuits electrically isolated from the ac power line, relays are useful to switch ac power while keeping the control signals electrically isolated. The electrical relay offers a simple on/off switching action I response to a control signal. When a current flows through the coil of wire a magnetic field is produced. This pulls a movable arm, the armature that forces the contacts to open are closed; usually there are two sets of contacts with one being opened and the other closed by the action, This perhaps an electric heater in a temperature control system. DESIGN ASCPECT OF COMMUNICATION HyperTerminal is a program that is include with every version of the Microsoft windows operating system and allows your PC to function as a computer terminal to connect with other systems remotely. The remote systems are mainframe computers that provide a programs that accept a terminal on the other end of the connection. HyperTerminal allows your PC to function as a terminal son you can connect to an internet which is an internal network such as a library network or an internet access server. RS232 Communication Information being transferred between data processing equipment and peripherals is in the form of digital data which is transmitted in either a serial or parallel mode. Parallel communications are used 6

7 mainly for connections between test instruments or computers and printers, while serial is often used between computers and other peripherals. Serial transmission involves the sending of data one bit at a time, over a single communications require at least as many lines as there are bits in a word being transmitted(for 8-bit word, minimum of 8 lines are needed). Serial transmission is beneficial for long distances for short distances or when very high transmissions rates are required. In addition to communication between computer equipment over a telephone lines, RS-232 is now widely used for direct connection between data acquisition devices and computer systems. As in the definition of RS-232, the computer is data transmission equipment. However, many interface products are not data communication equipment. Fig.9 Pin Configuration of RS-232 Table1.Shows Pin Configuration ALGORITHM Fig.10 RS Start 2. Initialize LCD 3. Initialize serial port 4. Get Transformer voltage from ADC 5. Display voltage on LCD 6. Get transformer current from ADC 7. Display current on LCD 8. Get transformer temperature from ADC 9. Display temperature on LCD 10. Check if any data received serially if yes go to Check if card inserted if not go to Send card number to PC 13. Go to If data received = CMD_relay_on then turn ON the relay and go to If data received =CMD _info_off then turn Off relay and go to If data received =CMD_Info_Off then send parameters to PC and go to Go to Stop 7

8 IX RESULT AND DISCUSSION 1. K. Raja Saranya and K. Ram Prasad An Efficient Monitoring of Transformers Using Microcontroller Based System Bonfring International Journal of Man Machine Interface, Vol. 2, Special Issue 1, February 2012 Fig.11 Indicator When oil reaches 55 C the information is send To PC through microcontroller X.CONCLUSIONS In this paper we have presented the design of system on microcontroller that is used to control and monitor the voltage, temperature, current of the distribution transformer. The proposed system has been design to monitor the parameter of transformer continuously as long as operation of the transformer. If the microcontroller senses any small change in any parameter like voltage, current, temperature beyond the perticular level the unit has been made to shut down throgh the PC but shows the values of parameter throughout the process for the user reference. This prooves that the proposed system proves to be robust against the key power quality issues which makes the voltage, current, temperature to peak. Hence distribution can be make more efficient, safe, suitable by the proposed sysytem. XI.REFERENCES Fig.12 Alarm Indicator When Oil temperature is reaches to the limit alarm will be operated. 2. Vivek Kumar Sehgal*1, Nitin2,Durg Singh Chauhan3, 1,2,3Member, IEEE and ACM Embedded Controller Based Smart Card Access Proceedings of the World Congress on Engineering and Computer Science 2008WCECS 2008, October 22-24, 2008, San Francisco, USA. 3. Yog raj sood, Raj kumarjarial, kapil Gandhi Condition monitoring power transformer using sweep frequency response analysis MIT International journal of Electrical & Instrumentation Engineering Vol. 1, No. 2, 8

9 Aug 2011, pp ISSN MIT publications. 4. AmitSachan Department of Energy & Power Engineering NIMS University, Jaipur, Rajasthan Microcontroller Based Substation Monitoring and Control System with Gsm Modem IOSR Journal of Electrical and Electronics Engineering (IOSRJEEE)ISSN: Volume 1, Issue 6 (July-Aug. 2012), PP