3 Phase Digital Watthour Meter (original) (raw)
Related papers
2012
This paper presents an electronic three phase watt-hour meter based on the MSP430F449 microcontroller. The developed system features a capacitive power supply obtained from the three phase network and circuits for signal conditioning to deal with the voltage and current signals. To protect the system from the grid’s eventual power failures, a battery with a charging management system is included. The measured data is stored in a Flash memory and can be displayed through an LCD. Remote communication modules are implemented which allow infrared communication, serial port and optocouplers. The system’s software implements the measurement of the voltage and current signals with a sample rate of 1 kS/s.
Design and Development of a Microcontroller Based Digital Wattmeter (MIDIWAT).
This paper presents a design to produce a microcontroller based digital wattmeter that measures the magnitude of power consumption of various loads (electronic devices) connected through it. To measure the power consumption under a sine wave signal (AC supply), the root mean square (rms) of both voltage and current is multiplied. The design is implemented using the techniques of digital signal processing and transformation. By this approach, both voltage and current are sampled a number of times during a cycle, the rms of the signals, real power, apparent power and the power factor are computed on the discrete signals. Finally, the magnitude of the power consumption is computed by integrating the power usage over a period of time. Product of this effort is a MIDIWAT that can measure rms voltage and current and power consumption over a period of time up to 1 kVA of loads (± 2%) with an overload protection
The aim of this project is to build a simple, compact and energy-efficient system for measuring Active Power, Reactive Power & Power factor using a microcontroller based board. It is based on microcontroller along with a zero crossing detector circuit. Current transformer and potential transformer are used for gathering real time current and potential data. It is fed into the microcontroller via a zero crossing detector (ZCD) built using High Precision Operational Amplifier. ZCD converts current and voltage waveform to square wave. From the directly received phase data, microcontroller calculates the phase difference and hence the power factor of the system. Then from voltage, current and power factor the Active power and Reactive power can be calculated by the algorithm written on the microcontroller. The measured and calculated value of Active power, Reactive power and Power factor is displayed on the LCD screen.
A novel TDM-based high precision wattmeter
2016 Conference on Precision Electromagnetic Measurements (CPEM 2016), 2016
A novel high-precision wattmeter is developed based on a standard watt converter design using time-division multiplication. A commercial 22-b delta-sigma A/D converter is used for the measurement of the watt converter output dc voltage. The measurement results are presented on a local display. In addition to power, the instrument measures ac voltage and ac current and displays their measured values on separate displays. Two prototypes were tested and compared with an existing standard watt converter connected to a high-precision digital voltmeter. The measurement results are presented and analyzed. Achieved measurement uncertainties (k = 2) of the power measurement are better than 50 µW/VA.
Generally single phase a.c power consume in domestic electrical appliances i.e fans, freeze, washing machines and three phase power consume by bulk consumers like as industries, institutions, shopping malls etc. Study of three phase power is a part of basic Electrical Engineering course which is mandatory for all discipline students to aware the idea of types of a.c active, reactive and apparent power which is in all Technical Universities in India and abroad. This topic is also a part of in Laboratory of their curriculum. Three phase power can be measured by different methods which are one wattmeter, two wattmeter and three wattmeter methods. In these, two wattmeter is cost effective, time saving measurement of three phase power. Software based Practical are less costly than hardware base practical and also have a provision to change the circuit parameters as they need compared to hardware based results, which is better understanding of students in learning concepts of Basic Electr...
Design and implementation of a low cost fault tolerant three phase energy meter
Measurement, 2008
This paper presents design and implementation of a microprocessor based intelligent three phase energy meter that measures accurate energy, even at the presence of harmonics. Moreover, if a fault occurs in any one of the potential transformer (PT) secondary circuits or the pressure coil in the measuring device, the unit can sense the fault and register the actual energy. Microprocessor provides a simple, accurate, reliable and economical solution of these problems. A framework of hardware circuitry and assembly language program for evaluation of energy values have been given and the problems which should be paid attention to execute the proposed algorithm using microprocessor has been discussed. Illustrative laboratory test results confirm the validity and accurate performance of the proposed method in real-time.
VERSATILE MULTIFUNCTION ELECTRICAL DIGITAL METER BASED ON PERSONAL COMPUTER
mit.bme.hu
The objective of this work is to describe a versatile multifunction electrical digital m eter based on personal computer; it has been developed for incorporation into a laboratory testing system. The meter uses two 12-bit A/D. The A/Ds are connected to parallel printer port of PC. The work was developed for Measurement of power. Using a programming language Turbo C++ was calculated: rmsVolts, rmsAmps, volt-amps, Reactive Power, Phase angle, frequency, Active power, watts-hour, resistance, capacitance and period. The values are shown at the monitor as a 4-digit display. The accuracy of meter is within 0.1%. The virtual power meter has a virtual two-channel oscilloscope. The meter was developed to senses power supply of electronic devices. (TV, PC) and electromagnetic device.