microcontroller based power theft identifier project and implimentation
Active In SP
Joined: Mar 2010
08-04-2010, 12:05 PM
sir,im a student of b.tech finalyearnd i wanta full detail and project and implimentation report of microcontroller based power theft project and implimentation
Active In SP
Joined: Apr 2011
08-05-2011, 11:43 AM
hi friend you can refer these pages to get the details on microcontroller based power theft identifier project and implimentation
http://topicideas.org/how-to-microcontro...ll-seminar and presentation-report
http://topicideas.org/how-to-microcontro...ll-seminar and presentation-report?page=23
http://topicideas.org/how-to-microcontro...ll-seminar and presentation-report?page=5
http://topicideas.org/how-to-microcontro...ll-seminar and presentation-report?page=11
http://topicideas.org/how-to-microcontro...ll-seminar and presentation-report?page=21
seminar projects maker|
Active In SP
Joined: Sep 2013
23-09-2013, 04:43 PM
Microcontroller Based Power Theft Identifier
The present thesis, Microcontroller Based Power Theft Identifier, introduces the concept of preventing the illegal usage of the electrical power. Here, the radio communication principles are employed and also the technology of Microcontrollers is utilized to find out the user trying for pilferage of power i.e., by displaying the respective consumer meter number and address.
For the complete operation, the system can be sub-divided into two major sections, one is the transmitting section and the other is the receiving section. The transmitting section has to be incorporated at the consumer’s end and the receiver section has to be placed at the electrical sub-station. In the transmitting section, two types of automatic power theft detection schemes are provided. In the first scheme, within the meter (inside the bottom cover), an electro-optical sensor is placed and it is configured to feed trigger signal for the timer circuit. The receiver section consists of RF receiver to receive the signal transmitted from the home transmitter section. Since the energy meter at pole measure the same energy as measured by the home energy meter i.e. the energy delivered to the LOAD (various appliances).
This project and implimentation consists of mainly two sections. One section consists of energy meter, isolator and receiver + comparator situated on our supply pole and the one consists of energy meter isolator and transmitter, situated in our homes.
The energy meter 1 & 2 can measure the energy by measuring voltage and current. Voltage can measure directly with the help of voltmeter provided on the energy meter but for measuring current it requires a Current transformer (C.T.). The C.T. can measure current by measuring magnetic field induced from a current carrying thick copper wire using a coil. Energy meter consists of four LED’s to show the status. One LED (transparent red LED) blinks with a constant time interval. This time interval reduces with increase in LOAD.
The energy meter at our home measures the energy consumed by different LOADs. The output from energy meter (from blinking LED) is given to transmitter section through isolator. Isolator consists of a relay and a driver for switching it by energy meters output. The isolator prevents the transmitter section from high voltage output of energy meter. The isolator output is used to drive one out of four inputs of the transmitter. This signal is decoded using encoder IC HT12E and transmitted using RF transmitter module.
Power surge /drainage management:
The problem with using robot components that drain a large amount of power is sometimes your battery cannot handle the high drain rate, Motors and servos being perfect examples. This would cause a system wide voltage drop, often resetting your microcontroller, or at least causing it to not work properly. Just a side note, it is bad to use the same power source for both your circuit and your motors. So don't do it. Or suppose your robot motors are not operating at its full potential because the battery cannot supply enough current, the capacitor will make up for it. The solution is to place a large electrolytic capacitor between the source and ground of your power source. Get a capacitor that is rated at least twice the voltage you expect to go through it. Have it rated at 1mF-10mF for every amp required. For example, if your 20V motors will use 3 amps, use a 3mF-30mF 50V rated capacitor. Exactly how much will depend on how often you expect your motor to change speed and direction, as well as momentum of what you are actuating. Just note that if your capacitor is too large, it may take a long time to charge up when you first turn your robot on. If it is too small, it will drain of electrons and your circuit will be left with a deficit. It is also bad to allow a large capacitor to remain fully charged when you turn off your robot. Some things could accidentally short and fry. So use a simple power on LED in your motor circuit to drain the capacitor after your robot is turned off. If your capacitor is not rated properly for voltage, then can explode with smoke. Fortunately they do not overheat if given excessive amounts of current. So just make sure your capacitor is rated higher than your highest expected.
UNREGULATED POWER SUPPLY: -
These power supplies, supply power to the load but do not take into variation of power supply output voltage or current with respect to the change in A.C. mains voltage, load current or temperature variations. In other words, we can say that the output voltage or current of an unregulated power supply changes with the change in A.C.mains voltage, load current and temperature.
GENERAL DESCRIPTION :
The AD7751 is a high-accuracy fault-tolerant electrical energy measurement IC that is intended for use with 2-wire distribution systems. The part specifications surpass the accuracy requirements as quoted in the IEC1036 standard.
The two ADCs digitize the voltage and current signals from the current and voltage transducers. These ADCs are 16-bit second order sigma-delta converters with an oversampling rate of 900 kHz. This analog input structure greatly simplifies transducer interfacing by providing a wide dynamic range for direct connection to the transducer and also simplifying the antialiasing filter design. A programmable gain stage in the current channel further facilitates easy transducer interfacing. A high-pass filter in the current channel removes any dc component from the current signal. This eliminates any inaccuracies in the real-power calculation due to offsets in the voltage or current signals—see HPF and Offset Effects section. The real-power calculation is derived from the instantaneous power signal. The instantaneous power signal is generated by a direct multiplication of the current and voltage signals. In order to extract the real-power component (i.e., the dc component) the instantaneous power signal is low-pass filtered. Figure 2 illustrates the instantaneous real-power signal and shows how the real-power information can be extracted by low-pass filtering the instantaneous power signal. This scheme correctly calculates real-power for nonsinusoidal current and voltage waveforms at all power factors. All signal processing is carried out in the digital domain for superior stability over temperature and time.
OPTO- ISOLATOR :
An opto-isolator, also called an optocoupler, photocoupler, or optical isolator, is an electronic device designed to transfer electrical signals by utilizing light waves to provide coupling with electrical isolation between its input and output. The main purpose of an opto-isolator is "to prevent high voltages or rapidly changing voltages on one side of the circuit from damaging components or distorting transmissions on the other side. Commercially available opto-isolators withstand input-to-output voltages up to 10 kV and voltage transients with speeds up to 10 kV/μs
Phototransistors are inherently slower than photodiodes. The earliest and the slowest but still common 4N35 opto-isolator, for example, has rise and fall times of 5 μs into a 100 Ohm load and its bandwidth is limited at around 10 kilohertz - sufficient for applications like electroencephalography or pulse-width motor control. Devices like PC-900 or 6N138 recommended in the original 1983 Musical Instrument Digital Interface specification allow digital data transfer speeds of tens of kiloBauds. Phototransistors must be properly biased and loaded to achieve their maximum speeds.
Design with transistor opto-isolators requires generous allowances for wide fluctuations of parameters found in commercially available devices. Such fluctuations may be destructive, for example, when an opto-isolator in the feedback loop of a DC-to-DC converter changes its transfer function and causes spurious oscillations, or when unexpected delays in opto-isolators cause a short circuit through one side of an H-bridge Manufacturers' datasheets typically list only worst-case values for critical parameters; actual devices surpass these worst-case estimates in an unpredictable fashion. Bob Pease observed that current transfer ratio in a batch of 4N28's can vary from 15% to more than 100%; the datasheet specified only a minimum of 10%. Transistor beta in the same batch can vary from 300 to 3000, resulting in 10:1 variance in bandwidth.