Explore the direction of protecting the transformer power parity method

Power transformer protection is an important direction of backup protection of transformers. As adjacent components and the internal fault transformer backup protection plays an important role in preventing the expansion of the scope of the failure to ensure the safe operation of the system. Primary and secondary wiring secondary wiring, voltage transformer secondary wiring and protective devices has its  electric meter  relationship correctness, and current transformer, which in actual operation, it is easy due to the wiring polarity errors The misoperation or refuse to move. This paper attempts to explore the direction of power protection, summed up in a simple and reliable method of calibration. The results show that by  air circuit breaker the actual failure of the power system, combined with CT, PT wiring polarity analysis can simply and reliably protect the correctness of power direction direction can be tested, given the equipment acceptance and routine inspection work, which greatly simplifies the work amount.

Transformer backup protection operation causes and treatment

Transformer backup protection reasons are: the high-pressure side of the transformer short circuit. Transformer low-voltage busbar short circuit. Since the failure occurred within the differential protection, differential protection failure. Low line failure,  Voltage stabilizer  tripping, causing a transformer overload tripping. If the over-current protection, found that the voltage drop, shock, arc, sound and so on, to deal with external transformer checks; If timely troubleshooting, you can try to send one, or should be ready to take safety measures to repair; If no problems are found, also may try to send a; transformer differential  air circuit breaker  non-, in addition to external examination, it should also be measured to check the insulation. If the low-pressure outlet failure, line protection tripping, you can manually destroyed fault line switch, power transmission and transformer. If the differential due to a fault occurs within the scope of protection, differential protection failure, the differential protection should be handled.

Traditional contactor product-oriented design methods, using trial and error methods

Traditional contactor product-oriented design methods, using trial and error, long development and production cycles, low efficiency, high cost; and product performance and other aspects of electrical life is often difficult to achieve the desired targets. The merits of the dynamic characteristics affecting the performance of high-power DC contactor and electrical life is good or bad, is an important factor in the mechanical  electric meter . Therefore, the use of virtual prototyping technology to the dynamic characteristics of high-power DC contactor for analysis and optimization has important theoretical and practical significance. In this paper, a series of high-power dual-winding DC contactor for the study, based on virtual  power transformers  technology combined with the structural characteristics of the type of contactor, analyze its static mechanical properties of the reaction force, the establishment of an equivalent circuit model double  air circuit breaker , the development of direct contacts analysis of dynamic characteristics of virtual prototyping system, and thus on the dynamic characteristics of contacts to optimize the design in order to improve its reliability and electrical life. In this paper, multi-software co-simulation method to establish the dynamic characteristics of high-power DC contactor analysis model.

Electro-pneumatic contacts with compressed air as a power

Due to the high electric and diesel locomotives main circuit voltage, current large, so is used to turn off the main circuit and open contacts must have a larger opening and contacts from the contact pressure to prevent contact temperature is too high , and ensure that there is sufficient contact arcing when disconnected and insulation capability . Electro-pneumatic contacts with compressed air as power, fully meet these requirements , which are widely used in electric and diesel  mcb circuit breaker . But electro-pneumatic contacts have their innate weaknesses : ( 1 ) it is one of the key components to soften or harden rubber cup extremely dramatic changes in temperature and deterioration and cooperation between the cylinders , causing electrical action failure , thus failure ; ( 2 ) it uses  Voltage stabilizer  air as power, complicated duct runs , to a certain extent, affected the reliability of electrical appliances ; ( 3 ) its use of the environment has  air circuit breaker  requirements. It is because of these electro-pneumatic contactors weakness in foreign countries, has been widely used locomotive circuit electromagnetic contactor. With the rapid development of rail transportation technology, machine owners electromagnetic contactor circuit to replace the electrical contacts has become one of the empty trends . Meanwhile the city subway, oil drilling , plating, wind power and other industries also require high power DC electromagnetic contactor. Therefore, the development of new magnetic contactor has become essential.

Also increasingly electronic voltage transformer replacement in

In the power system , voltage transformer can play a role in protecting the power grid . With the sensor technology, intelligent technology and grid technology continues to evolve ,  Circuit breaker  advanced voltage transformers , voltage sensors began to digital signals, network transmission , and linear measurement direction of rapid development , in order to ensure the power grid to meet the increasingly developed requirements. In recent years, electronic voltage transformers , the abbreviation is EVT, in the power system has been widely studied , electronic  mcb circuit breaker  used in technology, including computer technology, optical technology and communication technology. In addition, with the continuous development of science and technology level , electronic voltage transformer also increasingly replacement , at present , there is a new type of high-voltage electronic voltage transformer has been around and has been used , this article  air circuit breaker  high-voltage electronic voltage transformer the sensing principle and structure . New high-voltage electronic voltage transformer of this new medium and high voltage electronic voltage transformer is based on the coupling capacitor EVT. Compared with conventional voltage transformer , this transformer has a high safety performance , relatively low cost , insulation performance, error is small , the control room environment is good and relatively simple to operate and so on. New high pressure EVT key structure, including: high-precision micro current transformer , coupling capacitors, and power amplifier .

Using fast saturable reactor type damping allows ferromagnetic resonance damping characteristics and transient response characteristics

In a foreign country more than fifty years of development history, made from 1964 CVT capacitor plant in power since the birth, also accumulated forty years of manufacturing and operational experience, has now matured. Especially in the last decade, CVT in accuracy and increase output capacity and the successful use of fast saturable  air circuit breaker  damping allows ferromagnetic resonance damping characteristics and transient response characteristics significantly improved, etc. has been a breakthrough. CVT has reached or exceeded electromagnetic voltage transformer (VT) of the performance  mcb circuit breaker , but also has a high dielectric strength, will not happen with the system  Voltage stabilizer  resonance, low prices and high voltage coupling capacitor for carrier doubles as a communication (PLC) and so on. Therefore, CVT in China's electric power system has been widely used.

E-glass fiber and its products have a range of excellent performance because

The transformer is an important power industry for substation equipment, ensure that the transformer operation safety and reliability, not only for the promotion of economic development and social progress of great significance, but also to ensure that people's lives and property also has a very important significance. E-glass fiber and its products because with a series of excellent performance, especially good  power transformers , high heat resistance, has been in power electrical industry has been widely used. In recent years, due to the power transformer and technological progress and product upgrading, glass fiber and its products in the manufacture of dry-type transformers, has become an indispensable important material.  air circuit breaker  of the development since the Faraday discovered electromagnetic induction has been more than a century ago is the earliest of the transformer dry-type transformers. Because of this transformer can not be bigger, high voltage can not do technically was extremely restricted. The emergence of  electric transformer technology development made an indelible achievements. Currently, the transformer industry mainly to produce mainly oil-filled transformers, which accounts for about 60% of total capacity to 70%. In the use of oil-filled transformers have some fatal disadvantages, limiting its wide application.

Substation secondary cable has extremely important problem of electromagnetic compatibility

With increasing voltage levels and secondary equipment more and more decentralized, substation secondary circuit already in a strong electromagnetic environment in recent years has multiple causes substation DC system disruption caused by the secondary  electri cenergy meter  no fault tripping accidents, which caused a serious threat to the grid, affecting the safe and reliable operation of power systems. Therefore, the study of secondary cable substation electromagnetic compatibility  Voltage stabilizer  a very important theoretical significance and practical value. This paper focuses on the finite difference time domain method based on  air circuit breaker  transmission line theory and electromagnetic interference on the secondary substation cable coupling situation.

Buried cables and coaxial with frequency-dependent parameters such as multi-conductor transmission line transient electromagnetic process FDTD calculation method

Get transfer impedance and transfer admittance amplitude-frequency characteristics, and the phase-frequency characteristics can be obtained, and the test system is relatively simple; applies not only to single-core shielded cable can also be used for multi-core shielded cable transfer impedance and transfer admittance measurement . With other methods of  electric meter  results were compared with measurements to verify the correctness of this measurement method. Proposed for research overhead lines, underground cables and coaxial cables with frequency-dependent  air circuit breaker  as multi-conductor transmission line transient electromagnetic process FDTD calculation. The main research results to establish a substation switching transients field time-domain simulation model, based on the spark  Voltage stabilizer , the isolation arc discharge channel switching operation, time-varying resistance and inductance formulas. A typical substation switching transients by fitting the measured field data obtained arc discharge channel switching time-varying resistance range. Based on this model to study the impact of switching transients field intensity and rise time of a variety of parameters for EHV and UHV substation switching transients field study provides a theoretical basis.

Secondary equipment electromagnetic compatibility problems have become increasingly prominent

With the ultra-high voltage grid, intensive direction and microelectronics technology in the wide application of the secondary equipment, substation electromagnetic Voltage stabilizer , secondary equipment, electromagnetic compatibility problems have become increasingly prominent, research substation switching transients and the effect on two times the cable coupling mechanism having a weightTo  mcb circuit breaker  and application value. This paper, based on finite-difference time-domain (FDTD) method to study the field of substation switching transients time-domain  air circuit breaker , substations and cable trench soil transient electromagnetic field distribution, bounded wave electromagnetic pulse (EMP) simulator transmission line designed for near-field Finite length cable coupling mechanism, as well as the transient electromagnetic field coupling cable numerical methods.

Fault Tree Analysis (FTA) to build a power transformer internal fault

Power transformer fault location method of providing practical basis. Analysis of power transformer fault detection technology, to further explore the power transformer internal fault detection and effective way. The use of fault tree analysis techniques (FTA) to build a power transformer internal fault classification  air circuit breaker , will be  electric meter  electric power transformer fault localization studies. Study the characteristics of ant colony algorithm, principles, algorithms and  Voltage stabilizer  model. Pheromone ant colony algorithm, the information heuristic function factor, the number of ants, ant colony algorithm expectations inspired performance factors on the impact of simulation studies.

When the material is corrosive or crystallization, may cause corrosion or wear of the valve seat

Pressure vessels and equipment commonly used security device has safety valve, explosion-proof tablets.  electri cenergy meter  proved that the reliability of the safety valve and the nature of the material being processed has a direct relationship between the corrosion resistance when the material or crystallization, may cause corrosion or wear of the valve seat, resulting in seal failure; when the material is  power transformers  the reaction. large amount of gas when the pressure within the vessels or equipment will rise sharply, requires a large passage area, this time, the use of explosion-proof film is more appropriate. Ex-piece safety device of simple  air circuit breaker , reliable work, by capacity, is used widely. At present, the domestic metal rupture disc has more in-depth research, has made great progress.

Tire Explosion agent is a top-secret American Aerospace 60s Supplies

Tire Explosion agent, recently passed the China National Quality Supervision and Inspection Center of rubber tires put an end to slow leak and instantly blocking the drain hole firmly tie performance testing and approval by the State Bureau of Technical Supervision, while achieving the security provided by the Northern Jiaotong University and the proof  mcb circuit breaker  Insurance Co., Ltd. provides quality  air circuit breaker , successfully received the automotive safety products into the Chinese market permits. Tire Explosion agent is a top-secret U.S.  Voltage stabilizer  1960s, the Gulf War into the military, has been converted to civilian use to decrypt, after years of extensive use, it can effectively protect automobile safety, to the maximum extent relieve traffic explosion due to leakage tie tires, caused by the loss and annoyance. Tire Explosion agent injection tires can eliminate slow leak, perforation can prompt asking for blocking prison, especially for automobile tires at high speed due to warming caused by the burst, better preventive effect. Also has a bullet-proof function. In addition, can extend tire life, save fuel.

Thereby reducing the explosive ammonium nitrate fertilizer; adding a small amount of proof agent

Ammonium nitrate crystals after being hit, the friction between the crystals and ammonium nitrate containing tiny bubbles  Circuit breaker produces a hot, fast diffusion and the formation explosion. For these two main reasons, the major modification methods are: by doing fertilizer, ammonium nitrate reduction in the content of  air circuit breaker , thereby reducing the explosive ammonium nitrate fertilizers; adding a small amount of proof agent, inhibiting its explosive, so that both high retention of  power transformers  fertilizer, but also reduce the explosive. The experiment by adding a small amount of thermal decomposition of ammonium nitrate explosion and inhibits the generation of hot spots, to ammonium nitrate explosive control. According to several experiments to determine the three-proof formulations were tested for various sensitivities.

Brush sparking or electrical contacts can always sparks ignite explosive gases, explosion test

Depots , mines and other places where flammable gases used in motors, electrical motors were tested must pass after a reasonable gap and then into the tank . Use explosion-proof .  Air circuit breaker  of flammable gases , such as fuel gas tank , exhaust pipe guide when inflated to protect the tank on top of a breakthrough kraft paper, etc. near the outside , the use of electrical appliances must also use explosion-proof . Because the motor unit plus Tiegai be ensured by mechanical means . Brush sparking or electrical contacts can always sparks ignite explosive gases, explosion test : as long as the gas concentration reaches a certain value can cause an  air circuit breaker . This problem is inside the motor and tank test spark plug with a high voltage generator connected ( ie, the old machine new machine design and modification can not be ignored . Automotive ignition coil ) , there are two  power transformers  . Explosion-proof electrical design structure, material selection should meet explosion-proof electric motor connected to the subjects within the spark plug power supply, the motor combustible gas blasting machine technical requirements. New trial and for each product line-item fried routine tests are required . At this point the gas tank can not explode. Identification method is to tank Bu side. Breakthrough kraft not explode . If you were blasted , indicating the subjects can not be flameproof motors .

Ex-wave plate for hanging protective properties of the shutter is more mature

Civil air defense projects ventilation equipment types used internally complex, the production process is relatively backward means of detection, product quality can not effectively ensure ventilation. In order to regulate the ventilation ventilation protective equipment performance testing, protective equipment to improve product quality, it is necessary to develop a standard set of test bench. Currently, hanging plate proof protective  power transformers  of wave shutter has been more mature, and the ventilation valve on the hanging board performance study was relatively small. In this paper, the shutter mechanism and close the ventilation air flow  air circuit breaker , hanging plate ventilation valve test bench is designed to provide a theoretical basis. Hanging plate valve closed model mainly by the base plate,  mcb circuit breaker , hinged seat and limit housing component. Close valve when hanging panels, new air vents through the hanging plate inside and out diffusion chamber. If the wind gradually increased from 0 to slow the increases to a certain extent from the rear overhang board is placed phenomenon, this time from the air flow is called swing wind; when ventilation rate continues to increase to a certain extent, then hanging plate closes and the the air flow is called close air volume. Put the wind from the air flow volume and turn off the ventilation valves belong performance.

Explosion wave shutter design and structural strength can withstand high intensity explosive shock wave case

Explosion-proof valve is to protect the front wave trenches engineering personnel protective equipment is one of the important survival. It is installed in the tunnel inlet and exhaust system of the head. Usually the shutter is open, trenches normal ventilation; after suffering a nuclear attack, the quick closing valve prevents the shock waves through the mouth of radioactive dust into the tunnel  electric transformer  inside to  Circuit breaker , equipment safety. Explosion wave shutter design and structural strength can withstand high intensity explosive shock wave case, within the fortifications on the tunnel personnel,  air circuit breaker  has played a crucial role. As foreign nuclear power development of weaponry to the United States, Russia, represented by nuclear states, and its missile hit accuracy are improved quickly. Such as: U.S. Minuteman ICBM Ⅲ roadbed, Russia SS.19 roadbed ICBM CEP reach 200m ~ 300m. It is estimated at 50 tons TNT equivalent touchdown burst conditions, positions at 240m radius from the explosion center, and its resistance at 25MPa, the survival probability of 54% (structure and equipment suffered minor damage, the device does not affect use); pair of precision-guided weapons in terms of a higher hit rate.

Industry Association club and Nanyang Explosion-proof motors Electric Institute jointly

With the deepening of reform and opening up, all walks of life has changed dramatically, with the rapid economic and technological progress and industrial development on the product performance, quality, a new and higher requirements. China Electrical  air circuit breaker  Association,  power transformers  electrical motor branch of Nanyang Institute teamed up with the explosion-proof motor industry and users  mcb circuit breaker  research, on the basis of proof on the motor according to the current standards, as well as a comparison with the motor, integrated in the explosion safety and quality, energy conservation, environmental indicators and other aspects of the production process problems and security risks, as soon as the products included in the proposed national phase-out product catalogs, stop the production and sale of referrals, the motor security flaws, the motor will be replaced motor is based on GB3836-83 "electrical equipment for explosive atmospheres" "General requirements" and part 2 "flameproof electrical equipment" design, manufacture.

Operator to enter the storage room and the plenum chamber shall not carry matches

If mixed with hydrogen in the air volume to the total volume of 4% to 74.2%, once the event sparks can cause a fire or explosion.  Air circuit breaker  to the hazardous properties of hydrogen, we have in the transport, storage and use of hydrogen process must pay attention to fire and explosion. 2 safety procedures ① operator must undergo a  mcb circuit breaker  and have higher job card issued by the department to mount guard, the operator strictly follow the rules and safety operation points executed. ②  power transformers  the storage room and the plenum chamber shall not carry matches, lighters and other fire, not easy to produce static wear chemical fiber clothing, shoes and shoes with nails to turn off the phone.

Emissions caused by excess hydrogen combustion and explosion has become a must attach great importance to solve the problems with

Because non-polluting electric cars, energy efficiency advantages to become the 21st century's most promising new type of environmentally friendly cars. Its power source, most lead-acid batteries, hydrogen - nickel batteries, cadmium - nickel batteries and so on. Some data indicate that these batteries in electric vehicles usage accounted for 78% to 95%. Since the widespread use of these batteries, the car is moving and the charging and discharging process, especially overcharge and  air circuit breaker occurs, the emissions caused by excess hydrogen combustion and explosion has become a must attach great importance to and solve the problem. The concentration of hydrogen explosions have certain limits, introduce real-time monitoring system, according to the National Motor Vehicle Safety Standard GB / T1 8384.1-2001 (hereinafter referred to as the standard) in the case of  power transformers  hydrogen concentration at the request of the concentration of hydrogen in real time detection and alarm. System Development  Air circuit breaker  in the charge to the battery, should be measured within the area specified by the manufacturer of the concentration of hydrogen in the exhaust gas; when the vehicle is traveling inside the hydrogen concentration measurement. According to this requirement, the need for real-time monitoring system within a predetermined area (charge) and the vehicle (traveling within) the hydrogen concentration detected.