| "Kyoto Protocol" set forth in one of the six | | | | maintenance oriented operation and space saving, |
| greenhouse gases sulfur hexafluoride (SF6) gas | | | | SF6 gas has also begun to high voltage |
| emissions into the atmosphere mainly through the | | | | transmission and distribution equipment in the |
| power transmission and distribution equipment, | | | | transformer, transmission pipelines and |
| especially high voltage switchgear, transformers, | | | | transformer areas such as application |
| transformers and gas insulated transmission | | | | development. At present, Japan is the country |
| pipelines and other products are in the | | | | with the largest production of SF6 transformers, |
| experimental research, manufacturing, | | | | Mitsubishi, Toshiba, Hitachi, Fujitsu can produce. |
| transportation and operation and maintenance | | | | SF6 transformers can be done at present levels |
| generated in the process. | | | | of 500kV and 300MVA. I also have the domestic |
| SF6 gas in high voltage electrical products account | | | | production 10kVSF6 transformers, some of them |
| for about the application of SF6 gas applications, | | | | with foreign companies set up a joint venture and |
| 80%, while the SF6 gas switch device is currently | | | | have the 110kV and above, SF6 transformer |
| leading the field of high voltage switch products, | | | | manufacturing capacity. In addition to high voltage |
| but also ultra high pressure and special high | | | | SF6 gas circuit breaker in the transmission and |
| voltage switchgear applications and development | | | | distribution equipment, GIS, load switches, |
| of the main directions, so understanding of the | | | | transformers, transformers and gas transmission |
| environment changes and trends in the protection | | | | pipeline is applied, there are a small part of the |
| and control emissions of SF6 gas into the | | | | SF6 gas is used in sports shoes, scuba diving with |
| atmosphere to study the SF6 gas in the power | | | | breathing apparatus, medical field, thermal |
| switching devices for power switching applications | | | | insulation glass windows, casting technology used |
| of great significance to the development of | | | | to protect the gas, pneumatic tires, and military |
| equipment. | | | | and other non electrical equipment. |
| Atmospheric environmental protection situation | | | | As the world power industry development, |
| December 11, 1997, 149 countries and regions, | | | | especially in recent years, China's sustained and |
| representatives, adopted the "Kyoto Protocol" | | | | rapid development of power industry in order to |
| provides for six greenhouse gases (GHG), which | | | | meet electricity demand, steady increase in grid |
| are: carbon dioxide, methane, nitrous oxide, | | | | construction and renovation, making the number |
| hydrofluorocarbons, perfluorocarbons , sulfur | | | | of high voltage power transmission and |
| hexafluoride. This Protocol was February 16, 2005 | | | | transformation equipment, demand for an |
| came into effect, which provides that during the | | | | unprecedented growth, increased SF6 gas usage, |
| period from 2008 to 2012, the main industrial | | | | but also an increase of SF6 gas into the |
| greenhouse gas emissions by developed countries | | | | atmosphere emissions. SF6 gas for electricity can |
| in 1990 on the basis of an average of 5.2%, of | | | | be seen that the contribution of the building the |
| which the EU will be six kinds of greenhouse | | | | greater the contribution to atmospheric |
| gases emission reductions of 8%, 7% reduction | | | | greenhouse effect is also increasing. |
| of United States, and Japan 6%, Canada 6% | | | | SF6 gas emissions into the atmosphere means |
| reduction, Eastern European countries, reduction | | | | SF6 gas emissions to the atmosphere mainly |
| of 5% to 8%; New Zealand, Russia and Ukraine | | | | through the power transmission and |
| do not have to cut emissions can be stabilized at | | | | transformation equipment, pressure testing of |
| 1990 levels; Protocol while allowing Ireland, | | | | new products, capacity, breaking test, factory |
| Australia and Norway, respectively, compared | | | | test, transfer of equipment, transportation, |
| with 1990 emissions increased by 10%, 8%, 1%; | | | | installation, operation, equipment maintenance and |
| developing countries have emission reduction | | | | so on. The United States during the period from |
| obligations. | | | | 1998 to 2002 the production and processing of |
| China on May 29, 1998 signed the "Kyoto | | | | high voltage circuit breakers installed in the SF6 |
| Protocol", August 30, 2002 formally approved the | | | | gas leakage rate were investigated. As a result, |
| "Kyoto Protocol", although China has not provided | | | | 10% of the circuit breaker leak may exist. |
| herein emission reduction obligations, but experts | | | | Leakage reason: 73% occurred in the gas |
| predict that China's C02 emissions will soon | | | | installation, 21% is due to worn and damaged |
| overtake the U.S. as the world's first one, when | | | | casing, and 6% is due to leakage of gas |
| the time will inevitably be to fulfill the "Kyoto | | | | containers. |
| Protocol" emission reduction provisions. In the | | | | SF6 gas emission reduction measures and |
| "Eleventh Five Year" period made it clear that to | | | | development trend of SF6 electrical Direction of |
| fulfill the "Kyoto Protocol" obligation, so SF6 gas in | | | | development of high voltage electrical products, |
| other appliances, such as transformers, | | | | especially the SF6 high voltage electrical products, |
| transformers, load switches, transmission pipelines, | | | | should be to reduce emissions of SF6 gas to the |
| etc. The application and development of SF6 gas | | | | atmosphere, the direction of the development of |
| into the atmosphere should be considered the | | | | specific measures include: 1, raising the |
| emissions, the study of more environment | | | | technological level of manufacturing process |
| friendly enterprises to adapt to the economic | | | | equipment, reducing the leakage rate of SF6 |
| development programs. | | | | electrical equipment. 2, to promote the |
| Characteristics of SF6 gas The study found that | | | | miniaturization of SF6 electrical equipment and |
| at atmospheric pressure under the uniform | | | | reduce the volume of SF6 electrical equipment in |
| electric field strength of SF6 gas insulated air | | | | order to reduce the use of SF6 gas. In order to |
| three times, although less than the insulating oil | | | | significantly advance the miniaturization of GIS and |
| and the high vacuum state, but the increase of | | | | non SF6 technology, Mitsubishi Electric Co., Ltd. to |
| SF6 gas pressure, the insulation strength will be | | | | SF6 gas and thick film dielectric coated electrode |
| higher than that of insulating oil, and high vacuum. | | | | composite insulation system as an object to |
| With air contrast study also found that, in the arc | | | | study the insulating properties of high pressure |
| discharge cases, the air temperature gradient is | | | | areas. By using thick film dielectric coated |
| relatively small, rough arc, SF6 gas, the overall | | | | together, can achieve curb the size of the metal |
| temperature is lower, mainly concentrated in high | | | | electrode effect caused by the breakdown |
| temperature parts of the arc. Therefore, SF6 gas | | | | electric field decline; can reduce the electrode |
| in the arc cut off very quickly after the cooling, | | | | space, the largest gas field, to achieve device |
| insulation and resilience of good air about 100 | | | | miniaturization. As far as possible a high degree of |
| times. SF6 gas on the environmental impact of | | | | integration, layout and flexible composite electrical |
| SF6 gas molecular weight is 146, the air density is | | | | appliances or HGIS. |
| about 5 times. SF6 gases in the atmosphere to | | | | 3, developing low pressure of the SF6 switchgear |
| survive life is 3200 years. Therefore, SF6 gas is a | | | | and SF6 gas mixture of electrical equipment. |
| very strong greenhouse gases. SF6 is a | | | | Countries in the world has been studying |
| greenhouse gas CO2 to the atmosphere of | | | | alternatives to SF6 gas for many years abroad |
| 23900 times. | | | | on a variety of mixed gases (such as SF6 N2, |
| In addition, SF6 gas switch device in the process | | | | SF6 CO2, SF6 CF4) in the PD characteristics of |
| of breaking currents will produce arc, the arc will | | | | insulation breakdown characteristics of the study |
| SF6 gas under high temperature decomposition, | | | | found that for the liquefaction temperatures were |
| but also will produce metal vapor arc of contact, | | | | particularly low, non toxic and stable N2 gas, |
| due to the presence of water in interrupter will be | | | | mixed with 20% of the SF6 gas and the non |
| broken down, decomposed material will produce | | | | uniform electric field in the partial discharge |
| secondary reaction to form HF, S02, SOF2, | | | | starting voltage (PDIV) and dielectric breakdown |
| SOF4, SO2F4 and other harmful substances. | | | | voltage (BDV) has increased the possibility of, and, |
| These substances will be corrosive internal metal | | | | also found in high gas pressure, can get 100% |
| components, if these substances emitted into the | | | | SF6 gas with roughly the same insulating |
| atmosphere on the person's body can cause | | | | properties. So SF6 N2 is considered the preferred |
| injury and stimulation. | | | | alternative to SF6 gas. At present, the world's |
| Application and Development of SF6 Gas In 1953, | | | | first hybrid gas insulated high voltage lines N2 SF6 |
| the United States first SF6 gas used in 115kV load | | | | in Geneva completed. ABB has developed LTB |
| switch devices, in 1958, Westinghouse created a | | | | 72.5 kV a 145kV GCB and HPL72.5 300B1 type |
| tank along the lines of the compressed air circuit | | | | GCB can be used either pure SF6 gas can also be |
| breaker 220kV double pressure type SF6 circuit | | | | used SF6 N2 gas mixture. When using SF6 N2 |
| breaker. The principle of this circuit breaker | | | | mixed gas, at 20 ? Rated air pressure 0.7MPa |
| through the SF6 gas from compressed gas | | | | (absolute), it can be used in 50 ?, while in pure |
| cylinders (1.5MPa) the flow of low pressure gas | | | | SF6 gas 0.5MPa (absolute), the only for 40 ?. |
| chamber (0.3MPa) and the cooling breaking arc. | | | | Toshiba also N2 SF6 mixed gas circuit breaker is |
| With this double pyramid structure, also developed | | | | studied. |
| the ceramic pole SF6 circuit breaker. Followed by | | | | 4, in the equipment manufacturing and equipment |
| Europe and Japan on the SF6 gas switch device | | | | maintenance during the use of advanced SF6 gas |
| manufacturing technology research has made | | | | recovery unit, the recovery through a variety of |
| great progress and development. The emergence | | | | filters to remove the SF6 gas in the water, oils, |
| of SF6 circuit breaker is a high voltage power | | | | dust, and other elements resultant decomposition. |
| system circuit breaking in from the oil circuit | | | | Achieve SF6 gas recycling. |
| breakers, compressed air circuit breaker | | | | 5, in the medium voltage (12kV 40.5kV) areas, |
| technology has begun a series of technological | | | | use of non electrical SF6 and vacuum switchgear, |
| advances of recent results. | | | | high voltage (40.5kV ~ 252kV) fields to the |
| It is with the oil circuit breakers, compressed air | | | | special high voltage (800kV 1100kV) areas, to |
| circuit breaker advantage is that a single fracture | | | | develop a vacuum circuit breaker (VCB), to |
| compared with the high voltage, arc quenching | | | | upgrade technology and equipment to reduce |
| ability, breaking current, circuit breaker, light | | | | manufacturing costs VCB, vacuum switchgear to |
| weight, operate small power, high reliability, low | | | | achieve a large number of high pressure area so |
| maintenance, avoiding the oil circuit breakers | | | | that active rejection vacuum circuit breaker |
| prone to fire breathing, fuel injection and other | | | | (VCB) of high voltage oriented research work, to |
| undesirable phenomena, in addition to structural | | | | achieve high voltage of VCB and EHV oriented. |
| diversification interrupter chamber (variable air | | | | 6, protection of atmospheric environment, and |
| pressure to open away from the ceremony, | | | | foster awareness of emission reduction. Japan is |
| scheduled to open away from the pressure air | | | | the use of SF6 gas more countries, in order to |
| type, self energy type and mixed type) and so | | | | implement the "Kyoto Protocol" on SF6 gas |
| on. | | | | emission reduction obligations, NEC Business |
| SF6 gas switch equipment, the continuous | | | | Association, the Japanese electric industry to |
| development of the structure of different types | | | | achieve this goal will be taken positive action. |
| of products, such as the tank and ceramic column | | | | Japan SF6 gas reduction measures is to establish |
| SF6 circuit breakers, GIS, HGIS, compound and so | | | | a check curb emissions, to replace SF6 gas |
| on. Including GIS, HGIS, and complex type can | | | | insulated equipment curb emissions, recycling |
| have a wide variety of product layout, these | | | | system, and has taken action to improve the SF6 |
| features allow the user in the design of power | | | | gas management system. Germany's high voltage |
| system substation, it can be selected according to | | | | switching equipment industry is also very well |
| different situations. Since 1979, China began to | | | | developed. Annual use of SF6 gas is about 1000t. |
| introduce, or with foreign countries to develop | | | | In order to achieve reduction of SF6 gas emission |
| 72.5kV ~ 550kVSF6 high voltage switchgear, | | | | targets, October 19, 2005, the power to run |
| after decades of development, SF6 electrical | | | | industry and electrical equipment manufacturing |
| appliances manufacturing enterprises increased | | | | industry associations and Solvay Fluor GmbH (SF6 |
| year by year. Currently, domestic enterprises can | | | | gas manufacturing) companies and the German |
| produce medium voltage (12kV), high voltage | | | | Environment, Nature Conservation and Nuclear |
| (40.5kV ~ 252kV), EHV (363kV ~ 550kV), and | | | | Reactor Safety for further provisions of the |
| ultra high voltage (800kV 1100kV) SF6 high | | | | Federal Ministry of have reached a consensus on |
| voltage switchgear. | | | | their own obligations. |
| Because SF6 gas has excellent insulating and arc | | | | 7, to carry out the Clean Development |
| quenching performance of the electrical | | | | Mechanism (CDM), to achieve reduction of SF6 |
| installations to achieve the economic oriented, low | | | | gas. |