FEATURES OF PRECISION MEASUREMENT OF ELECTRICAL ENERGY AT INDUSTRIAL FREQUENCY

The electric energy meter error for system operation because of stealing brings, will cause loss of energy meter measuring electric energy electricity, and affect accuracy and integrity of energy settlement. In real work, we not only need to view real-time electric energy meter display and measurement value which copied back by remote meter reading system, for example the secondary current, voltage, power, power factor, use instrument and phasor diagram in order to analyze and judge the electric energy meter running state whether there is electricity stealing to the user of electricity consumption of the large fluctuation. Calculating the corresponding correct electricity and electricity stealing amount can provide technology g uarantee for the accurate measurement of electric energy.

The introduction of static electric energy meter together with voltage and current distortions in the electric networks are revolutionizing the measurement of the electrical energy. Several questions and studies are proposed in the scientific literature concerning with metrological and reliability aspects of the actual electrical energy measurement. The European Directive on Measuring Instruments (MID) represents a different spin on setting the performance and safety requirements for those meters. Another European group, the OIML (International Organization for Legal Metrology) has published the document D11 discussing recommendations for legislation to meet the MID. An OIML technical committee is drafting the recommendation (IR46) that would give regulatory bodies an easily-adoptable set of requirements and tests to meet the needs of the MID. The recent literature have faced different issues concerning with the active and reactive electrical energy measurements in terms of definition, physical meaning and measurement methods. With the introduction of the MID directive, the actual discussion involves aspects as the metrological characterization of the meters. The paper proposes an analysis of the test settings imposed by the actual MID-harmonized standards, regarding the electric energy metering. The aim is to check if there are some degree of freedom in the test settings that could compromise both result reliability and the compliance/non-compliance of a given apparatus.

This paper clearly proposes a plug-in and replacement method for electric energy meters to standard meters. The standard meter is connected to the power meter power circuit. In the process of dismantling an old energy meter and assembling a new one, an energy metering loop is created based on a short-circuit fault in a converted energy metering device. In the whole process of changing the meter, the standard meter is used to complete the electric energy measurement. This paper can complete the electric energy measurement in the whole process of changing the meter, and prevent the property loss caused by the neglect of electric energy measurement when the meter is not successfully changed at present. The three-phase 0.02 portable multi-purpose electric energy standard meter is selected for this method, which can ensure the measurement accuracy. At the same time, the formulation of the left and right blocks and short-circuit fault pieces of the junction box of the electric energy metering equipment can ensure that the electric energy meter to be disassembled and the newly assembled electric energy meter are fully disconnected during disassembly, and the electric energy metering circuit of the power-on standard meter can be protected.

Electrified railway in China has been actively developed. At the same time, as a kind of impact load, the load of electrified railway traction substations has brought in a significant impact to the accurate measurement on the electric energy. This paper measured and analyzed the field electric parameters of several electrified railway traction substations, and analyzed the causes of the metrology result differences between the impact load electric energy meter and the ordinary electric energy meter. This work laid the foundation of further research on the accurate measurement of harmonic electric energy.

The introduction of static electrical energy meter is revolutionizing the measurement of the electrical energy. Several question and studies are proposed in the scientific literature concerning with metrological and reliability aspects of the actual electrical energy measurement. Different issues are applied for the active and reactive electrical energy measurements. The former seems to be assessed in terms of definition, physical meaning and measurement methods while discussions are carried out about aspects as the metrological characterization of the meters. The latter shows a number of opened questions on all of the above-mentioned measurement issues. Even if the scientific community agrees on the significance and metrics characterizing the active energy measurements, none information seems to be given about the quantitative relation between the power quality disturbances and the efficiency in the active electrical energy consumption. More in detail, even if it is well known that polluted environments and electrical transport systems always reduce the efficiency of an electrical system, it would be useful to determine the quotes of loss of active electric energy power due to the disturbance respect to the ideal case. the paper proposes an extended sensitive analysis with a double aim: (i) to quantitatively estimate as distortions in the voltage and current waveforms modify the efficiency in the consumption of electrical active power, and (ii) to validate in experimental environment the relation, defined in the IEEE 1459 standard, which links the active power consumption and synthetic PQ indexes as the total harmonic distortion.

With the gradual advancement of modernization, electric energy plays an increasingly important role in social construction and residents' life. In order to ensure the economic interests of the electric power department and consumers, regular accurate measurement and detection of electric energy in the substation is particularly important. This paper presents an electric energy metering and detection algorithm based on Stacking algorithm.

With the continuous improvement of manipulate and keep requirements of electric energy metering equipment, the traditional manipulate mode has long been unable to meet the new requirements. It is revealed that the commonly used fuzzy control algorithms can be attributed to some interpolation method, which is an approximation to the response function, equivalent to the fitting of the discrete response function. Aiming at the problems of unscientific task allocation, unreasonable path planning and inability to respond to dynamic demand in the traditional mode of manipulate and keep in power grid enterprises, a new dynamic optimization model and its solution algorithm are proposed. The continuous increase of social electricity consumption brings challenges to electric power enterprises, but also provides opportunities for the expand of electric power enterprises. As an indispensable part of electric power production and manipulate, electric energy measurement is directly linked with the economic benefits of enterprises. The purpose of this paper is to analyze the electric energy measurement based on the research of model control. In the research, the corresponding algorithm formula and model diagram are established to analyze it. In the research, it can be known that the manipulate and keep of its electric energy metering equipment will have a certain impact on it, reaching 50.42%. The research in this paper has important reference value and foundation for the future research in the fields of electric energy measurement.

Electrical energy meters are designed for measuring, recording, and monitoring of the consumption of electrical energy in residential, commercial, and industrial premises. Working measurement standards of the unit of active electrical energy are used for verification of energy meters, which are in turn subject to regular calibration. Working measurement standards are calibrated by calibration laboratories (CLs). Interlaboratory comparisons (ILCs) for calibration of measuring instruments are essential to ensure the accuracy, reliability, and reproducibility of measurement results across laboratories. The results of these comparisons in terms of a specific calibration constitute important evidence for national accreditation bodies. Two CLs participated in an ILC for calibration of the active energy meter: SE “UKRMETRTESTSTANDARD” – UMTS, Ukraine, and ELGAMA-ELEKTRONIKA, Lithuania. The participating laboratories performed measurements of active electrical energy at an alternating current of 230 V at a frequency of 50 Hz at calibration points from 0.05 to 10 A at power factors of ±1 and ±0.5 Lag. The energy measurements of both CLs can be traced back to CLs in Germany. The results of the ILC of energy measurement standards demonstrated a satisfactory consistency of the obtained calibration results. The laboratories meet the established requirements for the En value (UMTS – from 0.02 to 0.20; ELGAMA – from 0.02 to 0.19) and have confirmed their technical competence. The UMTS is accredited by the National Accreditation Agency of Ukraine (NAAU), and the ELGAMA is accredited by the National Accreditation Bureau of Lithuania (LNAB). Both NAAU and LNAB are among the participants of the ILAC Mutual Recognition Arrangement (ILAC MRA). Both CLs meet the requirements of the international standard ISO/IEC 17025. All this contributes to the recognition of calibration results of the laboratories in their scope of accreditation, both at the national and international levels.

Electricity-stealing defense is one of the chief steps in distribution network reconstruction. The electronic energy meter is an important invention for measurement energy power system, which is an effective measures for the electricity-stealing defense. And one-time seal technology makes stealing ways reduced to the limited several specific ways that are undercurrent tecnology, undervoltage teconology and phase-shifted teconology. All these ways are stealing electricity in front of the energy meter. Due to these methods of electricity-stealing and actual demand of defending stealing electricity, based on a digital three-phase electric energy meter, The equipment of electricity-stealing defense electronic energy meter is designed, which adopts Atmega 128 as the control core, uses a low power consumption and a high accuracy ADE7758 as the energy metering unit, takes use of the output impulse of standard electricy measure module and user electric energy meter to calculate and judge electricity-stealing by comparing the reading RMS voltage and current from the ADE7758 with the ZigBee wireless acquisition module. Energy meter can communicates with the concentrator by 485, infraned or carrier module. The energy meter sends the effective data back to the concentrator. It is showed that this system can not only accurate measurement of electrical energy, but also to accurately determine the occurrence and electricity-stealing and the time of stealing is also recorded, which bring great convenience to the power system.

Background: To solve the problem of accurate measurement of nonlinear harmonic electric energy, a method for improving harmonic electric energy measurement based on the discrete wavelet packet decomposition and reconstruction algorithm was proposed. Objectives: A reactive energy measurement method combined with Hilbert transformation was designed, and the frequency characteristics of wavelet function were discussed. An excessively high sampling rate could reduce the accuracy of harmonic power measurement. By setting the discrete wavelet packet transformation decomposition, the stepping of the wavelet form resulting from the excessively large wavelet packet decomposition scale was eliminated using the moncoband reconstruction algorithm. Methods: Experimental results showed that the detection error obtained by numerical simulation using the wavelet transform algorithm was close to the standard instrument, with the maximum reference error of 0.013%-0.030%. Results and Conclusion: The feasibility and measurement accuracy of the nonlinear harmonic electric energy metering system were verified, providing an effective method for accurately detecting the harmonic, interharmonic, and time-varying harmonic components of the electric power system.

State estimation theory is widely used for telemetry verification. Similar approaches can successfully be applied to electric energy measurements. Testing equations method was proposed in the frameworks of the state estimation theory and adopted for bad energy measurements detection. It is proposed to employ the modified testing equations method for detecting the systematic measurements errors of automatic electrical energy meter reading complexes. It is shown and confirmed that provided the statistical sample it is possible to detect and evaluate the systematic error, which, in turn, allows taking this error into account and adjusting the measurements results.

The different reactive power and energy metering methods used by electric energy meters on medium and high voltage consumers present different results between themselves, notably in the presence of distorted voltage and current signals. Over recent decades, many discussions and various propositions have been put into action, all of which aimed at a worldwide unification of power and reactive energy metering methods. However, the problem still persists and the objective of this study therefore lies in performing of a quantitative update, concerning the impacts of these different methods on the reactive energy metering for billing purposes. In this context, each of the methods frequently used by the electric energy meter manufacturers will be covered in an analytical manner, seeking the mathematical understanding of the divergences that exist between them. In concurrent fashion, calibration tests will be performed in the laboratory aimed at the correct quantification of measurement deviations found under specific distortion conditions in voltage and current waveforms, when comparing meters from different manufacturers and models. A new electric energy meter, that contemplates all known metering methods, was developed with the aim of performing a measurement campaign allowing for the comparison of the performance of each one of these methods under real load conditions, considering many different types of consumer. The obtained results, in addition to providing a quantitative update of the magnitude of existing deviations, also demonstrate a great concern regarding the lack of isonomy currently found around the world in the metering of reactive power and energy.

To overcome disadvantages of the conventional electric energy measurement system (CEEMS) in 10 kV distribution network, the study presents a high-voltage electrical energy meter (HVEEM) comprised of signal sensors, two measurement units, a synthesis unit, power supplies, and extended communication devices. With measurement chip circuit boards floating at 10 kV potentials, HVEEM accomplishes electrical energy measurement at the primary side. With the whole structure, HVEEM can be calibrated as a whole, and the synchronisation error makes no difference on its whole error. As the core component, the capacitive voltage divider (CVD) acts as not only the voltage sensor but also the power supply. The stability of CVDs, which is almost not affected by temperature, can be improved by the manner of voltage accelerated ageing for a certain time. CVDs for power supplies are able to output enough power for measurement chip circuit boards even if a single-phase ground or an opening fault occurs. The tests both in the laboratory and the field prove that HVEEM has substantial advantages over CEEMS especially in accuracy and reliability.

In our time, electrical energy has been used in all household and industrial settings. This is achieved by the ability of the device to convert it into another form of energy – mechanical, lifting, light, heat, and many more. etc., and vice versa. Exactly this variety of energy converters enables the development of electronics, communications, transport, health, energy, but also the search for and the creation of new sources and converters known as alternative sources of energy.The generation and consumption of electrical energy does not end there. In order to assess the quantity and quality of the generated electrical energy, special devices known as electric meters are needed. Measurement of electrical energy is important for both households and industry, as well as for its production and efficient use. There are different methods and means for electrical energy measurement. They work on the basis of different physical principles – induction, electromagnetic, galvanomagnetic, etc., but the task of all of them is to show the result of the current and voltage integrated in time.Various methods are known for the basic parameters measurement defining the value of electrical energy (electrical current and voltage). With the development of microelectronics, and in particular of sensor technology, various sensor transducers have been developed to measure electrical energy through a high precision electric circuit using a contact and/or contactless method. One of the most commonly used sensor transducers for measurement of electrical current in modern energy meters are magneto-sensitive ICs. They are characterized by high reliability of the output signal, temperature and electrostatic steadiness and not least a long period of trouble-free operation1. The sensible element in magneto-sensitive ICs is most often a Hall element or a magnetoresistor. It measures the current flowing through the conductor by converting the magnetic field around it into electrical voltage. The advantage of magneto-sensitive ICs is possibility in a semiconductor chip to create sensitive element and a processing and forming signal circuit. This makes the measuring channel more secure and compatible with integrated circuits for processing and transmitting measurement data.The article presents an experimental model of an electronic module for electrical energy measurement in a single phase AC current circuit. The measuring module is realized on the basis of a specialized integrated circuit ADE series of the Analog Device Company for electrical energy measurement and a current channel, realized by a magnetic-sensitive integrated circuit ACS of the Allegro MicroSistem Inc. for electrical current measurement. Presented are a block and schematic circuit diagrams, experimental design and experimental results showing the performance of the device.

With the continuous improvement of the automation level of the electric energy metering system, the measurement security threats it facing increased contrast. Aiming at the fuzzy and dynamic characteristics of the information safety grade of the electric energy metering system, a multi-level and multi-factor security comprehensive evaluation model based on dynamic fuzzy theory which proposes a safety classification evaluation method based on dynamic double fuzzy reasoning, was established based on the study of the security static evaluation model. In this paper, the information security evaluation index system is established by analyzing the related factors of confidentiality, integrity and availability of electric energy measurement information security. The dynamic fuzzy probability vector of the safety grade is calculated based on the ameliorated D-S evidential theory, then the static weight determined by FAHP based on triangular fuzzy number and the time weight determined by the information entropy weight method based on time degree are integrated to calculate the dynamic weight vector of the index, and finally combines examples to analyze and verify the resulting data. This paper provided new solutions for the information security classification evaluation of the electric energy metering automation system.KeywordsMeasurement automationSafety indexFuzzy theoryTime weightDynamic assessment