ENERGY METER PDF
The meter which is used for measuring the energy utilises by the electric load is known as the energy meter. The energy is the total power consumed and utilised . Objectives. • To understand the basic construction and different components of a single phase induction type energy meter. • Explain basic principle and. Detailed information and tools for energy meter interfaces can be More information about approvals of energy meters for billing purposes are given on the.
|Language:||English, Spanish, Dutch|
|Genre:||Academic & Education|
|ePub File Size:||18.54 MB|
|PDF File Size:||8.86 MB|
|Distribution:||Free* [*Regsitration Required]|
The energy meter is an electrical measuring device, which is used to record developed electronic energy meter is also available in the market but in view of. PDF | It is undoubtedly that in the future, energy would cost more as the The idea of designing the Digital Household Energy Meter is due to the basis that it. PDF | The energy metering technology used presently in Nigeria is not highly reliable and requires substantial labour and time to read.
The galvanomagnetic effect was achieved in semiconductors having a thickness greater than their length [ 1 ]. Better sensitivities were achieved using semiconductor materials such as InSb with Te as the preferred dopant atom [ 2 ]. AMR sensing technology was based on materials derived from binary and tertiary alloys of Fe, Ni, and Co, such as permalloy, deposited over a Si substrate.
The GMR basic structure is composed of two layers of ferromagnetic material Fe, Co, and Ni alloys separated by a non-magnetic material like Cu. In practice, in order to have high magnetoresistance variation, new magnetic multilayers structures were fabricated by repetition of the basic structure unpinned sandwiches, antiferromagnetic multilayers, and spin valves [ 5 , 6 , 7 , 8 , 9 , 10 ].
TMR sensing technology is based on the magnetoresistive effect that occurs in a magnetic tunnel junction MTJ structure where the modulation of its resistivity is due to the spin-dependent tunneling effect SDT. Once this effect was observed and technologically developed at room temperature, the design of new TMR-based sensors was made possible [ 11 , 12 , 13 ].
An MTJ element is composed of two ferromagnetic layers separated by an isolation layer. Usually, in the sensing technology, one of the ferromagnetic layers has immobilized its magnetization state pinned due to the presence of an antiferromagnetic layer [ 14 ], whereas the magnetization state of the second ferromagnetic layer is free to vary with the external magnetic field. The isolation layer is made of oxides such as MgO or Al2O3 [ 15 , 16 ].
The layer thickness of TMR structures is between 0.
For industrial applications, TMR sensors are implemented in a Wheatstone bridge topology. Each resistor of the bridge is made of a series association of — MTJ elements, for improved electrical robustness [ 18 ]. TMR technology offers sensors with improved features in sensibility, linearity, thermal stability, and low consumption with respect with previous AMR and GMR technologies [ 19 ].
In the design of power monitoring systems and energy meters, the current sensing technology methods have been addressed for the use of shunt techniques, commercial current transformer-based probes, or Rogowski coils [ 20 , 21 , 22 ]. Magnetoresistive MR sensors offer an interesting alternative in applications where power processing requirements need compact and simple solutions.
An experimental setup to process power with an MR sensor was developed in Reference [ 23 ]. It measures active power in the order of various tenths of milliwatts requiring additional circuitry to satisfy the flipping coil requirements.
The features of MR-based watt converters have been analyzed using non-Wheatstone type MR topologies [ 24 , 25 ], or based on the bridge topology but at the level of integrated circuit monitoring, although not for industrial applications [ 26 ].
Considering previous current measurement techniques, resistive current shunts have ohmic losses that generate heat and do not provide electrical isolation.
Hall-effect-based sensors need high permeability materials such as ferrites and, although isolation is well-provided, they have high volume and weight [ 27 , 28 ]. MR technology has developed current sensors with higher sensitivities without the use of ferromagnetic cores.
The eddy current is induced in the disc because of the change of the magnetic field. This eddy current is cut by the magnetic flux.
The interaction of the flux and the disc induces the deflecting torque. When the devices consume power, the aluminium disc starts rotating, and after some number of rotations, the disc displays the unit used by the load.
Electronic Energy Meter Based on a Tunnel Magnetoresistive Effect (TMR) Current Sensor
The number of rotations of the disc is counted at particular interval of time. The disc measured the power consumption in kilowatt hours. Braking system — The permanent magnet is used for reducing the rotation of the aluminium disc.
The aluminium disc induces the eddy current because of their rotation. The eddy current cut the magnetic flux of the permanent magnet and hence produces the braking torque. This braking torque opposes the movement of the disc, thus reduces their speed.
The permanent magnet is adjustable due to which the braking torque is also adjusted by shifting the magnet to the other radial position. Registration Counting Mechanism — The main function of the registration or counting mechanism is to record the number of rotations of the aluminium disc.
Their rotation is directly proportional to the energy consumed by the loads in the kilowatt hour. The rotation of the disc is transmitted to the pointers of the different dial for recording the different readings.
The reading in kWh is obtained by multiply the number of rotations of the disc with the meter constant. The figure of the dial is shown below.
Working of the Energy Meter The energy meter has the aluminium disc whose rotation determines the power consumption of the load. The disc is placed between the air gap of the series and shunt electromagnet. The shunt magnet has the pressure coil, and the series magnet has the current coil.
The pressure coil creates the magnetic field because of the supply voltage, and the current coil produces it because of the current. The interaction of the eddy current and the magnetic field causes torque, which exerts a force on the disc. Thus, the disc starts rotating.
The force on the disc is proportional to the current and voltage of the coil.The three phases have voltage only relative to each other.
Some meters have an open collector or IR LED output that give ms pulses for each metered amount of electrical energy, usually pulses per kWh. The series electromagnet is excited by the load current flow through the current coil. Braking system — The permanent magnet is used for reducing the rotation of the aluminium disc.
Monitoring and billing methods[ edit ] Commercial uses[ edit ] Large commercial and industrial premises may use electronic meters which record power usage in blocks of half an hour or less. In "three wire" or "three wire delta," , there is no neutral but an earth ground is the safety ground. This flux causes the eddy current Ies on the disc.