Design of Distributed Substation High Voltage Electrical Equipment Online Monitoring System Based on Image Segmentation Technology

As an important support mechanism for real-time monitoring and display of system frequency, harmonic voltage, harmonic current, three-phase voltage unbalance, voltage fluctuation and flicker, true power factor and other power quality parameters specified in national standard, especially for fast and accurate data processing and improving test frequency and level, the online monitoring of substation is an important support mechanism for real-time monitoring and display of system frequency, harmonic voltage, harmonic current, three-phase voltage unbalance, voltage fluctuation and flicker, true power factor and other power quality parameters specified in national standard. The research of distributed substation high voltage electrical equipment online system based on image segmentation has important practical value. However, the design system of the online monitoring network of some substation electrical equipment can not effectively follow the development needs of society and industry, and there is an urgent need for effective reform. Based on this, this paper first analyzes the problems existing in the design system construction of online monitoring network of distributed substation electrical equipment, and then gives the construction strategy of online monitoring system of high voltage electrical equipment in view of these problems.

Multiple three-phase induction motors connected to a zigzag transformer

Many experiments have been conducted in this research work which is (i) connecting a zigzag transformer with an induction motor, (ii) connecting a zigzag transformer with multiple induction motors, and (iii) connecting multiple zigzag transformers with multiple induction motors. These experiments provide a thorough understanding of the sequence network connections under the single-phasing condition of a three-phase induction motor. Moreover, these experiments protect the three-phase induction motors from unbalancing voltage supply and allow the induction motor to start under unbalance voltage supply. Additionally, they keep the three-phase induction motor running even any one of the three phases disconnected from the power supply without creating excessive heat in the motor winding.

The Performance of a Three-Phase Induction Motor under and over Unbalance Voltage

Voltage unbalance is an adverse global phenomenon impacting three-phase induction motor output. Three-phase source voltage may become imbalanced in a variety of respects, while a balanced system preserves stable voltage magnitude and angles in three phases, but a completely balanced state is difficult to get. Imbalanced cases may differ in multiple ranges which may practically affect the motor. So, this work is an effort to analyze the operations with appropriate propositions. The output of a three-phase induction motor working with an imbalanced supply grid, MATLAB/SIMULINK is further used for simulation purposes and programming based on the asymmetrical component approach is adopted. A new design for system rerating is being proposed. As a case study, a 10 HP three-phase induction motor was used. The findings of the study show that to determine the output of the induction motor, positive voltage series must be respected under the voltage unbalance factor (VUF) or proportion voltage unbalance index with six various voltage magnitude imbalance conditions, the copper losses of three-phase induction motors were calculated under full load conditions by simulation. So, the qualified percentage change in total copper losses for the motor operating under imbalanced and balanced voltages was determined.

Design of flowing refractometer with cylindrical insert in the form a vertical pipeline section for control to clear media state

The article a the new design of flowing refractometer of differential type for media condition control both in laminar and turbulent flow regimes is considered. Given the peculiarities of the location of the flow and closed cuvette and the angles of incidence of laser radiation on their walls we have implemented a new method of measuring the refractive index n in new developed design of refractometer. This allowed us to make the influence of a number of errors related with unbalance voltage on the photoelectric converter, with an increase in the number of reflections between optical elements of laser radiation, with the presence of a transport link for the selection of flowing fluid and temperature fluctuations on the result of measuring the refractive index. The technique allowing to reduce the influence of change of the optical density of the flowing liquid on the measurement error of refractive index is proposed. The results of experimental investigations for different media are presented.

Voltage Unbalance Impacts on Temperature of IE2, IE3 & IE4 Class Induction Motors

Energy efficiency actions is a shared policy goal of many governments in the world. In that sense, drive systems represent an important opportunity for energy savings. With an average of 20.1 million installed motors that represents approximately 30% of total energy consumption In Brazil, old motors sub-stitution for new and more efficient technologies is now a reality. The present work analyses the impact of voltage unbalance (VU) with under and over voltage on the line current and temperature of electric motors classes IE2, IE3 and IE4, the latter being a hybrid permanent magnet and squirrel cage motor. To do this, six different unbalance voltage conditions were applied to each motor while measurements were made to capture the main variations for each technology. The results show how the voltage unbalance results in considerable uneven increases in current and temperature in each motor, it was also observed how the hybrid permanent magnet motor shows less dependence on voltage variations, mainly with undervoltage.

Sistem Proteksi Motor Induksi 3 Fasa Terhadap Bermacam Gangguan Menggunakan Mikrokontroller

ABSTRACTIn the current era of globalization, various human jobs depend on electrical equipment such as three-phase induction motors. Three-phase induction motors are very important to use according to their roles and functions. The occurrence of voltage variations in the electric power system is due to the magnitude of the voltages between the three phases which are not the same so that there are differences in the angle of the R, S and T phases, which causes an uneven load overload in the electrical distribution system. Among the disturbances that can occur are overvoltage, under voltage, unbalance voltage between phases, overload, and overheating. Based on these problems, a three-phase induction motor protection system was designed, the system uses current, voltage, temperature sensors, which functions to measure the value when a disturbance occurs, a magnetic contactor as a breaker and a liaison when the disturbance is given in accordance with the set point value given to the microcontroller. The results of the research for unbalanced voltage of V1 112 V, V2 114 V, V3 108 V, overvoltage of V1 228 V, V2 207 V, V3 264 V, over current of A1 104 A, A2 107 A, A3 0.77 A , the overload on the resistance source is 333 ?, 250 ?, 200 ?, 167 ?, and the overheating is 40.75 ºC at 6.5 minutes with tripping conditions in each test. The final results of this study indicate that the protection system which is designed is better used for three-phase induction motors.Keywords: unbalaced, disturbances, protection systems, sensors, magnetic contactor, microcontroller.

PENINGKATAN EFESIENSI ENERGI GEDUNG L2 FAKULTAS TEKNIK UNIVERSITAS NEGERI JAKARTA MELALUI AUDIT ENERGI KELISTRIKAN DALAM RANGKA DETEKSI DINI TERHADAP BAHAYA KEBAKARAN

This study aims to identify the magnitude of energy consumption currently used and identify all possible energy savings including detecting all possible fire hazards based on audit data obtained using Power Quality Analizer (PQA) and Thermal Imager. The methods included include: collection and introduction of historical data, calculating IKE, measuring real power (kW) / apparent power (kVA), power factor, maximum / minimum frequency, voltage / current between phases, voltage / load unbalance, voltage harmonic / flow, checking Energy Consumption Intensity (IKE), recognizing the possibility of Energy Saving Opportunities (PHE), analyzing PHE, Making PHE recommendations and implementing PHE in the field to obtain the value of Energy Consumption Instances according to standards. Based on the measurement results show the carrying frequency, voltage fluctuations, voltage harmonics, and voltage imbalances are still in accordance with the standard. So that it can be concluded that the Faculty of Engineering, Jakarta State University, is still safe from the danger of building fires. Abstrak Penelitian ini bertujuan dilakukan guna mengidentifikasi besarnya konsumsi energi yang saat ini digunakan dan mengidentifikasi segala kemungkinan penghematan energy termasuk mendeteksi segala kemungkinan bahaya kebakaran berdasarkan data audit yang diperoleh dengan menggunakan Power Quality Analizer (PQA) dan Thermal Imager. Metode yang dilakukan meliputi: pengumpulan dan penyusuan data historis, menghitung IKE, melakukan pengukuran daya nyata (kW)/daya semu (kVA), faktor daya, frekwensi maksimum/minimum, tegangan/ antar phasa, unbalance tegangan/beban, harmonik tegangan/ , pemeriksaan Intensitas Konsumsi Energi (IKE), mengenali kemungkinan Peluang Hemat Energi (PHE), menganalisa PHE, Membuat rekomendasi PHE serta mengimplementasikan PHE dilapangan guna mendapatkan nilai Instensitas Konsumsi Energi sesuai standar. Berdasarkan hasil pengukuran menunjukkan bawa frekuensi, fluktuasi tegangan ,harmonisa tegangan, dan ketidakseimbangan tegangan masih dalam sesuai dengan standar . Sehingga dapat disimpulkan bahwa Fakultas Teknik Universitas Negeri Jakarta dari sisi kelistrikan masih aman dari bahaya kebakaran gedung.

The direct power control of three-phase AC-DC converter under unbalance voltage condition

This paper has presents the integrated approach for three-phase PWM AC-DC converter for obtaining the symmetrical components under unbalanced supply condition. The input structures for conventional direct power control have been modified with three simpler sequence networks instead it coupled by a detailed three-phase system method. In the cases of an unbalanced three-phase system, it causes the presence of unbalanced current and voltages thus produce the negative components on the grid voltage. Otherwise, the unbalance voltage in a three-phase power system causes severe performance degradation of a grid-connected VSI. Therefore, the imbalance voltage can be resolved by separating from the individual elements of voltage and current into symmetrical components called as a sequencing network. Consequently, the input power is relatively improved during unbalanced condition. It proven through the measurement of Total Harmonic Distortion (THD) from the conventional direct power control in individual elements is much higher compared than it resolved in separate components. Therefore, three symmetrical components are necessary for imbalance supply condition to obtaining almost sinusoidal grid currents.