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 .

Magnetic transformer circuit, the circuit frequency of the PZT-based, rather than the current duty cycle to control the fluorescent lamp

Magnetic transformer circuit , the circuit frequency of the PZT -based , rather than the duty cycle to control the fluorescent lamp . UCC3977 between the COMP pin with a pin and OSC formed programmable voltage controlled oscillator. The VCO operating frequency range for the system settings , the frequency range of the excitation frequency must PZT and the normal operating frequency is included . FB pin fluorescent lamp  electric meter  , and through PZT gain versus frequency characteristics can be controlled. PZT gain  electri cenergy meter  to be able to provide the minimum input voltage at the fluorescent lamp voltage, in order to ensure the control loop is always in the right side of the resonance . Work waveform push-pull circuit. N1 and N2 at 50% duty cycle is driven to generate the phase shift. Inductor L1 and L2  Circuit breaker  PZT primary capacitance , drain the N1 and S2 form a half sine wave. In the PZT voltage obtained across the primary near sinusoidal . Fluorescent voltage close to 600 volts in this application . Since the ceramic transformer has a high Q value, the voltage of the fluorescent lamp is a sine wave . To achieve zero- voltage switching , the drain voltage of the next switching cycle must return to zero before. This requires that the LC resonance frequency must be higher than the switching frequency.

The voltage gain of the transformer secondary winding through the turns ratio between the primary coil and

The voltage gain of the transformer can be determined by the turns ratio N2/N1 between the primary coil and the secondary coil of the transformer and the current gain is also related with N1/N2. In the design of the circuit for CCFL transformer primary inductance of the primary and turns the external capacitor resonant circuit formed by the transformer needed to decide. Secondary turns should be guaranteed to start  electric meter  lamps provide a high enough voltage. Secondary turns usually require high magnetic core has a large window area. As the high pressure primary and secondary isolation requirements between duty, CCFL transformer  Air circuit breaker  usually higher. This transformer is used as a sine wave, which only reduces the effective  Voltage stabilizer  of the turns ratio, and no switching spikes. Other problems associated with magnetic transformers also include the need to shield stray magnetic fields, as well as the potential arc fault condition at the time of the next level voltage control generated.

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 .

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

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.

Flameproof enclosure by a lever on the brass sleeve requires co-ordinated with copper sleeve

Button ring groove on the rod-proof products, many manufacturers now shell and front cover has a variety of button, the button bar is often used form of ring, ring effect is that once the explosion occurred inside the enclosure, the pressure acting on the button bar ends, the ring can be introduced to prevent the button rod outer shell, thus avoiding the formation of the button bar missing booster channels. It  electric meter , taken from a mechanical manual investigation groove depth is small, if roots unclear bottom pressure in the circular ring will follow the axial sliding movement relative to the button bar, the loss of a ring effect.  power transformers , the design of the groove depth should be appropriate bigger, processing bottom should pay attention to clean the root, or simply use the pin structure is more reliable. About flameproof enclosure by a lever on the brass  Voltage stabilizer  co-ordinated with copper sleeve, copper sleeve is an interference fit with the housing, and the joystick is clearance fit. Copper sets the amount of interference should not be too large, should be controlled not more than 0.05mm, copper sleeve wall thickness should not be less than 2.5mm.

Establish a complete system of electrochemical biosensor for the target

Biosensor application areas include medical testing, environmental monitoring, food safety and defense applications. This thesis is to create a complete electrochemical biosensor research system as the goal, making this system includes an electrode, the electrode modification and  electric meter  molecules fixed, electrochemical  Voltage stabilizer  methods to establish and develop miniaturized instrumentation, involving electrochemical biosensor implementation mechanism and application  air circuit breaker  of both studies, the specific states: I. Preparation of the biosensor electrode. By manual screen printing process to produce sheet type carbon electrode, as the majority of research work based on the biosensor electrode.

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.

As a suburban or rural substation overhead line switching control and protection

Easy to install and operate the pole circuit breaker. Mainly for urban overhead distribution lines segmented interval switching control and protection. Suburban or rural areas can also be used as an overhead line substation control and protection switching.  Voltage stabilizer  to oil-immersed  electric meter  breaking ability, oil inflammable, causing secondary disasters tend to be eliminated. After the 1980s, the use of SF6  power transformers  device with excellent performance, since the 1990s, began to adopt further operating power, long life of the vacuum interrupter. Typical pole breaker main technical parameters: Rated voltage 12kV, rated current 400,630 A, rated breaking current 6.3.

Hosted within the specified time, closing and breaking currents under abnormal

Can carry, closing and breaking the normal operation of the line currents can also be carried within the stipulated time, closing and breaking currents under abnormal (such as short-circuit current) switching equipment, power system protection and operation of the major electrical devices. Circuit-breaker many different types, but  power transformers  circuit are electrically conductive, insulating support member, and the interrupter  electric meter  composed of several parts. Basic structure include: ① a conductive main circuit, through the movable contact,  Voltage stabilizer  of the contacts on the circuit implementation and isolation; ② interrupter, the circuit breaking arc generated during the sealed chamber under a high pressure in rapidly within tens of milliseconds off, cut off the circuit;

Functionally graded piezoelectric material and related functionally graded piezoelectric bending drive

However, in practice the process of preparing the drive, a continuous distribution of the material component is difficult, replaced by a multilayer structure. In this paper, tape casting process to prepare a series of functionally graded  electric meter  material and related  Voltage stabilizer graded piezoelectric bending drive. The main contents include: the use of conventional solid phase synthesis method to prepare based piezoelectric ceramic powders; right PNN-PZT-based  circuit breakers ceramic powder slurry was cast performance studies; tape casting process used to prepare a series of casting sheet; Preparation piezoelectric properties and dielectric properties of a gradient in the thickness direction changes functionally graded piezoelectric material;

Developed a functionally graded piezoelectric actuators

Commonly used in the current construction of a piezoelectric single-, dual-chip driver at the interface between the layers stress concentration, resulting in the adhesive layer easily at a low temperature cracking, creep under high temperature, air circuit breaker  the life of the component. With different performance series PNN-PZ-PT material developed a functionally graded piezoelectric drive can overcome these  electric meter . In order to make a functionally graded piezoelectric drive gets large bending deflection, we need to high-voltage, low Voltage stabilizer  high strain piezoelectric material and low voltage, high dielectric properties combined with low strain piezoelectric material, and properties of the material composition and changes in the thickness direction of the gradient.

Can be driven by a low voltage, the ambient temperature is lower requirements

Giant magnetostrictive material (Giant MagnetostrictiveMaterial, GMM) drive has made ​​telescopic coefficient, output power, fast response, high accuracy and other characteristics, and the ability driven by a low voltage, the ambient temperature requirements are also low. Mainly used in precision engineering fields, such as ultra-precision  air circuit breaker , robotics displacement regulators, etc., can be precise and fast positioning, increase power output, with a high application value. In practical applications, the dynamic control of the actuator between the input current and output displacement exhibit significant non-linearity and the inherent  Electric transformer  of the material brought hysteresis nature. However, the implementation is applied at a low driving current, and quasi-static, since the magnetization process GMM mandrel may be similar to a static  electric meter , it is not significant hysteresis. On this occasion, the use of a GMM in the linear region, the input current and output displacement showed a linear relationship. However, due to the linear region of the smaller range, GMM trip shorter, so in some of the larger range of travel requirements of the occasion, such as high speed milling and hybrid motor design, the input current must be increased, increasing the itinerary.

Superfine grain size is reduced into the mill, to achieve more crushing less grinding most direct means

More crushing less grinding is home to beneficiation industry recognized an effective way of energy saving and superfine grain size is reduced into the mill, to achieve more crushing less grinding most direct means. Since the loop superfine mill product size can be broken down to 4mm. In this thesis, the theory and crushing equipment prototype test  electric meter  in-depth study, to improve the mill processing capacity, reduce over crushed, full use of resources and improve the economic efficiency of enterprises has important significance. Since the circulation of Kunming  air circuit breaker ultrafine mill is an efficient low developed patented new device. It uses the binder layer crushing, secondary crushing full use of the energy. Ore in the small roller outer wall and the inner wall of a large drum  electri cenergy meter  composed of automatic cycle, has been repeatedly broken. Device uses a clever forced discharging device, discharging material against water, mud affected. In the self-circulation superfine mill design and manufacturing based on a medium-pressure material layer crushing theoretical research, experimental research and broken particle size characteristics and regularity of power investigated crushing pressure, exhaust mine clearance, a small roller speed processing capability for self-circulation ultrafine grinding mill performance.

Research Status and piezoelectric actuator control system applied research

Studied the characteristics of piezoelectric actuators, applications, research status and application of piezoelectric actuator control system of the status quo. Studied the piezo inertial drive designs theoretical basis. Select the piezoelectric stack vibrator driven element, made ​​symmetrical electrical excitation  electric transformer  stack vibrator by controlling friction and inertia changes with the driving force of an orderly, drive the piezoelectric inertial  mcb circuit breaker  program. Design of flexible hinge adjustment mechanism to adjust the angle for the piezoelectric stack, thereby improving exercise performance piezo inertial drive. While selecting V-rail piezo inertial drive for the design,  electric meter and V guideways. These basic research work is based on V-rail piezoelectric stack inertia driver designed to provide a theoretical basis. Designed based on the V-rail piezoelectric stack inertial drives, developed experimental prototype, the basic performance of the prototype tests carried out relevant tests.

Theory and Two piezoelectric ceramic transducer mechanism and characteristics

Tests showed that the design of linear and rotary piezoelectric actuators to achieve the micro-nanometer positioning accuracy. The main contents are as follows: firstly analyzes the domestic and international research piezoelectric actuator status and application prospects, made ​​of piezoelectric self-sensing control technology  mcb circuit breaker h piezoelectric self-sensing inertial drive. Theoretical analysis of the piezoelectric ceramic transducer and two-way mechanism and characteristics in piezoelectric equations, and piezoelectric transducer bidirectional  electric meter matrix for the application of piezoelectric ceramics provide a theoretical basis.  air circuit breaker a piezoelectric wafer transducer finite element analysis model, theoretical analysis of piezoelectric wafer vibrator vibration mode piezoelectric output is the inverse piezoelectric characteristics and output characteristics.

Current manufacturing artificial current zero crossing will be very difficult

An important difference is that the former use of artificial zero-crossing method, the vacuum on the contacts current zero extinguish the arc, which is borrowed from the natural  Electric energy meter current arc. Although there has been applied to the VCB AC power system technology has matured, but it does not solve the current high rate of rise of the power system short-circuit current breaking issues. Since ACVCB is rated opening distance (a few millimeters to tens of millimeters) under breaking, usually takes a  electric meter  to tens of milliseconds, when the DC short circuit current rise rate 20A/μs when the short-circuit current  lectri cenergy meter will reach 100kA or more. Accordingly, to such a high current manufacturing artificial current zero will be very difficult, if achieved, will also lose the breaking limit of significance. A small opening in breaking away from the direct short-circuit current high rate of rise can be a good solution to the problem of excessive current. But a small opening under vacuum from the media recovery, but it is restricting the application of the method of the key issues. - At present, domestic and foreign media for the recovery characteristics of vacuum almost always based on a few millimeters to tens of millimeters at rated basis.

Cast resin dry type transformer noise pollution problems

Based on the basis of environmental protection, from cast resin dry type transformer component materials, operation, recycling point of view to analyze problems, and also studied cast resin dry type transformer noise pollution problem, the maximum extent  electri cenergy meter  cast dry-type transformers to meet environmental characteristics. Cast resin dry type  Voltage stabilizer constituent materials epoxy cast dry-type  electric meter  mainly by electromagnetic copper and aluminum materials, insulation materials and epoxy material. Epoxy resin as a flame retardant, fire, easily recyclable materials, its application greatly accelerate the development of dry-type transformers.

Production of dry-type transformers

Dry-type power transformers are widely used in all walks of life in the city has basically replaced the oil-immersed transformers, dry type power transformers in order to ensure safe operation, and do not need special maintenance and management personnel, dry type power transformers need to configure the temperature Tour electri cenergy meter control device (referred temperature controller). However, when the country can  electric meter  transformers, it was not producing  Air circuit breaker  device, rely on imports. Until 1992 domestic production began, then uses a discrete component technology, performance is poor, less functional, low precision, bulky, high failure rate, operation trouble. If using chip technology made ​​into a dry-type transformer intelligent temperature controller.