Epoxy cast transformer design and the protection of life

Reliability and service life of electrical products manufacturers and users are always issues of mutual interest , the design of electrical products rated life at different electrical applications and different times have different concepts and requirements, it should take into account the skill of the art progressive social and economic benefits of speed and overall , not too short, but not infinite . Just due to the rising level of loss or noise standards continue to improve and insulation technology makes  Air circuit breaker  transformer constantly being eliminated as a result , because they too old , although they may still use . In fact, a  electric meter  in its few years of its commissioning energy efficiency is much higher than the old scrapped a transformer consideration paid . Therefore , it should be relatively slow progress in the technology limited period of time to maximize the life of the product life design principles. Designed to protect the life and the life of electrical products is a systematic project , which involves the following six thematic areas : mechanical design and structural strength  mcb circuit breaker  ; electric field intensity electric field of design and aging ; temperature control and hot thermal insulation structure of the physical effects of aging ; nominal initial performance of the insulation structure life-giving ; wound repair , healing or regeneration projects ; protect electrical products rated operating environment. Which will affect the design or improper handling any aspect of their overall life , failure of any one link will lead to the end of life electrical products .

The system is running at less than optimal gain state, so light load conversion efficiency at light load conditions will also fall

The maximum inductance to satisfy this condition can be obtained from the following equation: When the drive circuit 600 volt fluorescent light, the efficiency curve of a multilayer PZT has a push-pull topology. When the input voltage is low, the conversion efficiency is higher than 85%; at high input voltage, the conversion efficiency decreases with the decrease in gain of PZT. Magnetic and  circuit breakers , the linear approach to reducing the fluorescent lamp dimming to reduce work efficiency. In the magnetic circuit of the transformer, the loss due to the circulating current in the resonant circuit with the generated electric current  mcb circuit breaker  the fluorescent lamp and maintain independent constant, the decrease in the conversion efficiency at light loads. In PZT circuit, since the system is running under light load conditions below the optimum gain state, the light load  Voltage stabilizer  efficiency will fall. Light load efficiency of these two circuits can be improved using pulse dimming technology. This method can visually sensed higher than the frequency modulation of the duty cycle by on / off control the average current of the fluorescent lamp, the fluorescent lamp working at full load current.

Magnetic transformer may be thicker, heavier and more inefficient

For the next generation of portable fluorescent display enclosure and become thinner , therefore , creates a demand for thin CCFL power supply . Thanks to the development of magnetic ceramic piezoelectric transformers and transformer , we can create a more efficient , smaller backlight converter. Select the transformer depends on the cost , size and efficiency , and several other factors . For example , at a given power level lower than the piezoelectric transformer , the transformer may be magnetic thicker , heavier and less efficient , but it also has a greater load range and a lower cost advantage . For the PZT transformer , the operation of the sine of its inherent characteristics . In addition, it has a high excitation voltage , non-flammable and non- electromagnetic noise , etc. . A transformer for example 3-4W laptop . About the high-frequency magnetic transformer transformer works by a  mcb circuit breaker  core and a plurality of coils wound on the composition . Transitions occur between the energy flux and the magnetic core. This energy exchange is a function of current and voltage of the integral : Energy = ∫ I Vdt = ∫ H dB change in flux density in the core can be used and the field intensity is expressed ; current in the coil can also be used , to express the change of voltage and time . The magnetic flux density and V - second proportional and  power transformers  to the number of turns of the coil and the core cross-sectional area . Calculated according to Faraday 's law : current and number of turns is proportional to the intensity and the field , and inversely proportional to the length of the coil . According to Ampere 's law , it can be expressed as : The relationship between the flux density and field strength determined by the magnetic permeability of the core ;

Mine vacuum electromagnetic starter coal mine power supply system is the key equipment

Mine vacuum electromagnetic starter is one of the key equipment in coal mine power supply system, it directly affects the reliability and safety of coal power production system, so the development of high  Voltage stabilizer  electromagnetic starter has a very important  Circuit breaker . In the development of multi-loop vacuum mining electromagnetic starter controller, enabling multiple combinations of mine control and protection of large two-speed or single speed motor. Mine development and current  mcb circuit breaker  electromagnetic starter. For motor overload protection established motor heating, cooling mathematical model, proposed the use of software to simulate the temperature rise of the protection methods; analyzing the characteristics of small ground fault currents based on the application of the principle of zero sequence power direction herein Select grounded branch; addition, overvoltage, undervoltage were analyzed and the corresponding protective measures. According to the site conditions, determine the control mode controller, developed a general scheme of the controller.

With the development of mechanical and electrical industry, electricity systems are becoming increasingly complex

With the development of mechanical and electrical industry, electrical systems become more complex, the traditional contactor or starter demanding. In order to meet the electricity  air circuit breaker , intelligent demand, electrical factory in developed countries with a wide use of computer technology to develop multi-functional. Intelligent, high-performance, high-reliability magnetic contactors and electromagnetic starter. Its main feature is mechatronics, computer technology will be introduced  mcb circuit breaker  control appliances, on the one hand to meet the requirements of the basic functions of traditional appliances, on the other hand the control of intelligent appliances, in particular, can increase the variety of functions, such as protection monitoring communication function, can be used for the separation of electricity network system components.

Excitation contacts between the armature and the core working air gap is too large

Diesel use that often appear overly excited contactor LC action lags, or the master controller handle a blade and electric control contactor operation after only a few field contactor pull, sometimes even exceeding 35 or more, resulting in mistaken crew electrical fault in the process of elimination in the field contactor suddenly pull away car,   mcb circuit breaker crew working to bring some difficulties . Cause : Auxiliary interlock -delay . Excitation contacts between the armature and the core working air gap is too large. Activities are not flexible and exciter armature contactor moving contact and arc chute connected to ground caused by excitation contactor guilty cards. Field contactor auxiliary starting coil  air circuit breaker  or anti- interlock contacts being exposed . Analysis: field contactor switched on only after all the only action , if one is turned slowly interlocking coil is energized will cause lag . Auxiliary contacts connected, breaking contacts by electrically controlled solenoid valve on the air cylinder control contact air source to achieve, it is sometimes due to poor lubrication, air cylinder , electronically controlled contactor guilty card , electronic control contacts on the electrically controlled valve stem wear due to prolonged use too short , thimble or curved top side , so that the compressed air into the pneumatic air cylinder device channel becomes smaller ;

Create mechanical system simulation model of the structure

A solid modeling functions can complete the modeling of a simple structure, but for the mechanical system is relatively complex structures, it is difficult to obtain ideal model. In order to establish a more accurate three-dimensional model, must be combined with other 3D modeling software to build the structure of the mechanical system  mcb circuit breaker . Use modeling software UG, UG software can realize the concept of product design, industrial design, three-dimensional model design, analysis and calculation, dynamic modeling and simulation, engineering drawing output, etc., and has been widely used in aerospace, automotive,  electric transformer , shipbuilding , numerical control (NC) machining, medical devices and electronics and many other fields. Using ANSYS software to the AC electromagnetic contactor dimensional model, using UG software to establish a three-dimensional model bevel gear, but has yet to see software to establish communication with UG three-dimensional model of electromagnetic contactor.

Contactor main contacts prone to erosion or welding Symptom

In the machine tool equipment electrical maintenance practice, often encounter such a fault , that bear cage type motor forward and reverse control relay - contactor main contacts prone to  air circuit breaker  or welding failure phenomenon . The reason is nothing more than the main circuit or motor load , line occurred phase , overcurrent , overvoltage , overload and short circuit , or main contact capacity is too small , the device intrinsic poor quality, poor performance interrupter contacts , or action too frequent , and other mechanical factors . As a general rule , the causes of such failures are mostly obvious faults are relatively easy to exclude . But for other failure reasons, many maintenance personnel tend to notice , such as the device 's own action delay caused by the failure of its  mcb circuit breaker  device characteristics are mainly caused by differences contacts competitive mistakes, resulting in a system control the disorder causes the main contacts ablation or welding . For brief , it can do a simple closed  electric meter  test . See Figure back below. As we all know , the relay - contactor operation of its contacts off characteristics , always follow such a principle ; namely when the coil is energized regardless of the release will or power of the moment, by its own structural reasons , The control break before make contacts all follow the principles .

Street iron yoke plate between prolapse and changed the working air gap

Main contactor air cylinder and electric control valve leakage that insufficient air pressure, contactors slow movement; also electrically controlled contactor air cylinder and poor  Voltage stabilizer . Li ti excitation contactor iron working air gap between the core is too large: one is the field contactor coil and yoke gasket between the core mounting bolts loose or loose; second is the street between the iron yoke plate  mcb circuit breaker  and changed the working air gap. Activities are not flexible and exciter armature contactor moving contact arc hood connected with day wear caused by excitation contactor guilty cards. Analysis from the field  power transformers  part of the circuit can be seen only switched on only after all the action, if the three of them turned slowly interlocking coil is energized will cause lag.

Normal operation as the main power switch on the AC contactor

In use there, the normal closing operation as a total power 4OA AC contactor, and then operate a motor closing any other AC contactor, the total supply of both the control Bo OA AC contactor is disconnected. Disconnect motor circuit without load at startup, this  mcb circuit breaker  still exists. Therefore array analysis in machine electric stick into the line terminals, check with voltage tester has power display, with three-phase AC voltage meter to check the line voltage, phase voltage are in line  air circuit breaker . AC contactor without 4OA as the main power control, respectively, with AC contactor control 4 motors can work, but at the same time start two or more motors, the AC  electric transformer  on the trip. And starting with the direct method, you can also start the four electric motors. Find the above analysis, the total power and time lines identified no problems, the fault should be out in the second line.

Commonly used mobile substation high voltage isolation, low feed control mode

With the development of mining automation technology for coal mine power system reliability, security and continuity of the increasingly high demand . However, the original use of coal mine mobile substation high and low side switches with many problems . First of all, high and low voltage flameproof existing domestic leakage  mcb circuit breaker  malfunction different levels prevailing situation , not only caused a lot of unnecessary face power outage , but also to find the point of failure workers bring great trouble , serious affected production . Secondly, the original use of domestic coal mine with a commonly used mobile substation high voltage isolation , low feed control mode. High pressure switch is load switch , not breaking fault current ; low pressure side of the vacuum feed switch , breaking current is large . As well as to the low voltage winding transformer  Voltage stabilizer  failure can not be breaking the dead zone . Again, most do not have an existing switch network communication function , the workers only for high-voltage switch for close viewing and operation. To solve the above problems, the design and development project based on PLC control intelligent protection  electric meter  substation with high and low side switches. High voltage distribution switchgear with vacuum circuit breakers, low-voltage side of the feeder switch is not installed electrical protection box . High voltage distribution switch with overload, short circuit, phase , overvoltage , undervoltage, overtemperature protection function

High-voltage electrical equipment electrical porcelain importance and performance in the earthquake

Porcelain columnar sulfur hexafluoride circuit breaker for the study, carried out shaking table test and finite element analysis , the establishment of an effective system of electrical porcelain electrical equipment ( including shock absorbers, wire ) finite element model and the corresponding computational analysis method to study the seismic performance of high voltage electrical equipment and conductors for electrical equipment shock absorbers and seismic performance.  air circuit breaker  and obtained findings : porcelain -type high voltage electrical equipment and its importance in the earthquake performance. Damage data indicate that the high-voltage electrical equipment electrical porcelain damage is caused by high voltage grid system to destroy the key point, and the destruction of such  mcb circuit breaker  due to equipment damage caused by brittle ceramic column section . Accordingly, the seismic performance of such equipment in the past  Voltage stabilizer  on research ceramic column . According porcelain high-voltage electrical equipment as well as the structural features of the device at run-time state shows that the factors that affect the seismic performance of the device include: ceramic column , the connection between the ceramic column flange, equipment support , shock absorption and isolation device equipment , the wires between devices . This departure from these factors , summarizes the current research on these factors and problems , and identifies research content .

Maintenance of high voltage electrical switch gradually find methods and means stability

High-voltage electrical switch in the power system as a whole, an important part of our country safe and stable operation of power systems play an important and decisive role, but also directly affect the electrical safety of users. In order to maintain the stability of  mcb circuit breaker , people also began to attach importance to the stability of high-voltage electrical switch problem. Therefore, the power system workers also began by analyzing the stability of high-voltage electrical switchgear factors to gradually find maintaining the stability of high-voltage electrical  power transformers  and methods. Stability of high-voltage electrical switch basic status of high-voltage electrical switch of the power system as an important part, with the use of a wide range and number of features, its electric meter can give the entire power system operation caused by the security and stability the most direct impact of the development of high-voltage electrical switch China's electric power system operation and quality are closely related.

Electrical properties, oxidation resistance is poor, but good antioxidant susceptibility

Transformer oil to replace the electrical switch oil , which can not meet the required electrical switch oil insulating properties and low temperature properties .  electri cenergy meter  equipment is running , the occurrence of short-circuit current , oil often produce large amounts of free carbon , oil blackened , dielectric strength would drop dramatically ; short-circuit breaking generally occurs twice , it is necessary to stop oil treatment equipment , and thus had to frequently change oil , increasing fuel consumption . Dushanzi oil refinery production breaker  mcb circuit breaker , in particular the rare , far from meeting market demand. French import breaker better quality oil , but the variation in viscosity , slow settling of free carbon , colloid state easily , difficult to remove . Cycloalkane has good electrical properties, poor oxidation resistance , but the susceptibility of good antioxidants , and generally low pour point is an ideal  Voltage stabilizer  the insulating oil . So are the first choice of the world production of crude oil naphthenic insulating oil . Because less naphthenic crude oil reserves , so it developed from the middle of the base , even from the paraffin-based oil producing electrical switches . To meet the high-voltage electrical switch oil oil needs , we hydrogenated oils, benzene as raw material, developed in line with specifications SH/T0205-92 electrical switch oil, which are high-grade lubricants .

High voltage switching device is a transmission and distribution systems from the control and protection of the most important electrical equipment

National Grid to increase investment by the market economy, many factories have launched production of switching equipment. Where high pressure, high-voltage switchgear is transmission and distribution systems from the control and protection of the most important electrical equipment, is supported by the state major machinery and  mcb circuit breaker , revitalize national industry shoulder the historic mission. West Electric Group, Xi'an Switch Factory million volt level product assembly project for the steel construction. The project has outstanding characteristics, concentrated light steel, heavy steel lattice, grid, color plate roofing,  electric transformer , etc., due to process causes more building partitions, design and construction of complex, changing shape. Project Overview West Electric Group Western Cape million volt level product assembly project, with a total construction area of ​​20000m2, due to the production process is divided into eight  power transformers  segmentation, the main plant with a steel form. Buildings highest elevation 41m, maximum span of 60m. The main structure in the form of steel plants, including H light steel, lattice steel columns, grid and so on.

Fault tree diagnosis method is also known as fault tree analysis

Modern thermal power to keep the high-parameter, high-capacity, automated direction , while greatly improved plant efficiency , reduce costs , has brought huge economic benefits. On the other hand , once the equipment failure caused the loss will become Kazunari hundredfold  Voltage stabilizer  costs and time to grow exponentially. Thus, higher demands on equipment reliability , while eager to have a scientific and rational diagnostic theory and technology, the operational status of equipment for fast , accurate diagnosis , in order to ensure that the unit is not an accident, or if accident, to limit to a minimum . Fault tree  air circuit breaker  is also known as fault tree analysis method, is a failure of the system to the reasons for the formation by the general assembly by dendritic  mcb circuit breaker  refine methods of analysis. Fault tree diagnosis was " seeking the fruit because of" deductive analysis method was based on the failure to seek the cause of the process. The thesis of boiler fault diagnosis fault tree principle achievements of qualitative and quantitative methods, and rules . And according to Daqing Petrochemical Company Thermal Power Plant One boiler structure and technical characteristics of the boiler flue gas temperature is high , low, ash combustibles too large, such as boiler flue gas deflection establish fault and fault tree analysis.

Power Transformer Fault Diagnosis System

Power transformer complex structure, its failure in the form of complex. Traditional power transformer fault diagnosis method is offline transformer electrical test , this method is difficult to real-time fault detection and may cause excessive maintenance ; Another method is based on the analysis of dissolved gases in oil fault diagnosis method for the detection of faults is very valid, but can not locate the fault . Therefore, this research and the development of  mcb circuit breaker  fault diagnosis system . The main results paper : This paper presents fault tree-based support vector machine classifier design . First, the tree-based fault classifier used in the inverter fault diagnosis in the establishment phase inverter model and get 66 fault waveform using wavelet  electric transformer  singular value decomposition method to extract fault waveform characteristic value , and then use tree-based support vector machine waveform classification , the experimental results show that the tree-based support vector machines for  circuit breakers  timing sequence of more than 95% ; article will be based on fault tree support vector machine classifiers applied to the power transformer fault diagnosis the classifier can achieve the properties of the 10 transformer fault classification results show that the classification accuracy rate of 90 % or more.

Fault current protection function, can effectively reduce the scope of the accident

Pole circuit breakers for distribution lines exports segmented trunk, branch control such as the role of the switch, the current type SF6 circuit breakers and vacuum circuit breakers have two kinds. With the rapid development of power construction, pole circuit breaker has been widely used in the power system, it is easy to operate,  mcb circuit breaker  the operation of the distribution network flexibility, because of its fault current protection function, can effectively reduce the scope of the accident, shorten the search time of the accident, accident repair speed increase for reliable power supply to provide a strong guarantee. But in recent years, with the power of knowledge and electrically  Voltage stabilizer  popularity, many non-professionals (mainly distribution networks) have mastered the method of operation of the circuit breaker pole. For their own interests, often without the knowledge of the electricity sector, privately points on  electric transformer  operation, the power sector to the normal maintenance and repair work to bring great security risk. There are some criminals pole breaker operation is completed after stealing electrical equipment, causing great losses to the electricity sector. To solve the problem, we specialize in this phenomenon were summarized and analyzed, and fundamentally to be addressed.

Remote communications, such as one segment or automatic reclosers for the realization of true outdoor unattended substation provides an ideal product

High voltage vacuum circuit breaker has not due to blasting, low noise, small size, high reliability and suitability of the advantages of frequent operation is widely used. Hubei mcb circuit breaker ZW14A-12 type outdoor vacuum circuit breaker with RDCU series controller combination, form a set of computer protection, network  electric meter , CNC measurement, data logging, remote communications, such as one segment or automatic  Air circuit breaker  outdoors unattended substation provides an ideal product. Beijing Switch Factory developed ZW861-12 type column vacuum circuit breaker with C20E Intelligent Control protectors and outdoor PT combined.

Generator Circuit Breaker If you choose incorrectly, the circuit breaker will cause serious harm

Of the problem with the continuous development of science and technology and people's safety awareness generation equipment continues to improve, the generator breaker dedicated selection and use more and more cause for concern and attention, especially for large and very large  Electric energy meter  machinery exports particular attention to the choice of the circuit breaker . If you choose incorrectly generator circuit breakers , circuit breaker itself even be connected to the generator generators and other electrical equipment circuit causing serious harm and  mcb circuit breaker  losses, such as the explosion occurred breakers , generators burned, excitation transformer and plant with variable burned and other serious accidents , and will magnify the accident . For small hydro , the past mostly use an ordinary type of oil circuit breaker , vacuum circuit breakers , SF6  Voltage stabilizer . , especially in recent years , the choice of more and more common vacuum circuit breaker , such a choice is not comply with GB GB/T14 82 4-93 " generator breaker general technical conditions" and industry standards DL42 7-91 " indoor type GCB ordering technology " requirement, does not conform to international common standards However, the parties have failed to pay sufficient attention to this cause .