阅读说明：本技术 电介质流体和电气装置中的全氟化1-烷氧基丙烯 (Perfluorinated 1-alkoxypropenes in dielectric fluids and electrical devices ) 是由 肖恩·M·史密斯 迈克尔·G·科斯特洛 克劳斯·亨特泽 马库斯·E·希尔施贝格 威廉·M·拉 于 2018-12-12 设计创作，主要内容包括：本发明公开了一种电介质流体(即,电介质组合物),其包含由以下通式(I)表示的全氟化1-烷氧基丙烯化合物：R<Sub>f</Sub>O-CF＝CFCF<Sub>3</Sub>I其中R<Sub>f</Sub>为CF<Sub>3</Sub>-或CF<Sub>3</Sub>CF<Sub>2</Sub>-。此类电介质流体可用于各种电气装置中。(Disclosed is a dielectric fluid (i.e., a dielectric composition) comprising a perfluorinated 1-alkoxypropene compound represented by the following general formula (I): r f O‑CF＝CFCF 3 I wherein R f Is CF 3 -or CF 3 CF 2 -. Such dielectric fluids may be used in various electrical devices.)

1. An electrical device comprising a dielectric fluid comprising a perfluorinated 1-alkoxy propene compound represented by the following general formula (I):

R_fO-CF＝CFCF₃

I

wherein R is_fIs CF₃-or CF₃CF₂-。

2. The electrical device of claim 1, further comprising a reservoir, wherein the reservoir comprises a quantity of the dielectric fluid in liquid form.

3. The electrical device according to claim 1 or 2, wherein the electrical device is selected from the group consisting of a gas-insulated circuit breaker, a current interruption equipment, a gas-insulated transmission line, a gas-insulated transformer and a gas-insulated substation.

4. An electrical device according to any one of claims 1 to 3, further comprising one or more secondary dielectric gases.

5. The electrical device of claim 4, wherein the one or more secondary dielectric gases are selected from the group consisting of nitrogen, carbon dioxide, nitrous oxide, helium, argon, oxygen, and combinations thereof.

6. The electrical device of claim 4, wherein the one or more secondary dielectric gases are selected from the group consisting of perfluoroalkanes, fluorinated olefins, fluorinated ketones, fluorinated oxiranes, fluorinated nitriles, fluorinated nitroalkanes, fluorinated diketones, and combinations thereof.

7. An electrical device according to any one of the preceding claims, wherein the compound of formula (I) is in the trans configuration, cis configuration or a mixture thereof.

8. The electrical device according to any one of claims 1 to 7, wherein the compound of formula (I) is CF₃-O-CF＝CF-CF₃。

9. The electrical device according to any one of claims 1 to 7, wherein the compound of formula (I) is CF₃CF₂-O-CF＝CF-CF₃。

10. A dielectric fluid, comprising:

a perfluorinated 1-alkoxypropene compound represented by the following formula (I):

R_fO-CF＝CFGF₃

I

wherein R is_fIs CF₃-or CF₃CF₂-; and

one or more secondary dielectric gases.

11. The dielectric fluid of claim 10, wherein the one or more secondary dielectric gases are used in an amount such that the vapor pressure is at least 70kPa at 25 ℃.

12. The dielectric fluid according to claim 10 or 11, wherein the ratio of the vapor pressure of the secondary dielectric gas to the perfluorinated 1-alkoxypropene compound represented by formula (I) is at least 2.5: 1.

13. The dielectric fluid of any of claims 10 to 12, wherein the one or more secondary dielectric gases are selected from nitrogen, carbon dioxide, nitrous oxide, helium, argon, oxygen, and combinations thereof.

14. The dielectric fluid of any of claims 10 to 13, wherein the one or more secondary dielectric gases are selected from perfluoroalkanes, fluorinated olefins, fluorinated ketones, fluorinated oxiranes, fluorinated nitriles, fluorinated nitroalkanes, fluorinated diketones, and combinations thereof.

15. The dielectric fluid of any of claims 10 to 14, wherein the compound of formula (' I) is in a trans configuration, a cis configuration, or a mixture thereof.

Background

Dielectric gases are used in various electrical devices such as, for example, capacitors, transformers, cables or buses, circuit breakers and switchgear. In such electrical devices, a dielectric gas is generally used as an electrical insulator instead of air due to the higher Dielectric Strength (DS) of the dielectric gas. Such dielectric gases allow for higher power densities than air-filled electrical devices.

Sulfur hexafluoride (SF)₆) Has become the primary reserve dielectric gas in many electrical applications. SF₆Advantageously non-toxic, non-flammable, easy to handle, has a useful operating temperature range, and has excellent dielectric and arc interruption properties. Within the transformer, it also acts as a coolant. Blowers within the transformer often circulate gas to facilitate heat transfer from the windings. However, SF₆The problem of (a) is its 3200 year atmospheric lifetime, and a Global Warming Potential (GWP) that is about 22,200 times the global warming potential of carbon dioxide.

As a possible alternative, SF has been proposed₆With nitrogen, helium or nitrogen at elevated pressure. Perfluorocarbon (PFC) gases that can be mixed with nitrogen or helium are also identified; however, PFC gases also have high GWP values, thus limiting the possible reduction of the environmental impact of such strategies. Some other alternative mixtures suffer fromFree carbon emissions during arc discharge, increased toxicity during or after arc discharge, and increased difficulty in gas handling during storage, recovery, and recycling. Accordingly, other alternatives to such dielectric gases and mixtures thereof are needed.

Disclosure of Invention

The present disclosure provides compositions comprising one or more perfluorinated 1-alkoxypropene compounds, and methods of using such compositions.

In some embodiments, a composition is provided that includes a perfluorinated 1-alkoxypropene compound represented by the following general formula (I), which may be in the trans or cis configuration:

R_fO-CF＝CFCF₃

I

wherein R is_fIs CF₃-or CF₃CF₂-. Such compositions may be referred to as dielectric compositions or dielectric fluids.

In some implementations, such dielectric fluids may also include one or more secondary dielectric gases.

In some embodiments, an electrical device is provided that includes a dielectric fluid comprising a perfluorinated 1-alkoxypropene compound of formula (I) and optionally one or more secondary dielectric gases. In some embodiments, such dielectric fluids are insulators.

As used herein, the term "dielectric fluid" includes both liquid dielectrics and gaseous dielectrics. The physical state of a fluid, gas or liquid is determined under operating conditions using the temperature and pressure of the electronic device.

In this document, the terms "comprise" and its derivatives, are used in the specification and claims, and not to be construed in a limiting sense. Such terms are to be understood to imply the inclusion of a stated step or element or group of steps or elements but not the exclusion of any other step or element or group of steps or elements. By "consisting of," is meant to include and be limited to what follows by the phrase "consisting of. Thus, the phrase "consisting of" indicates that the listed elements are required or mandatory, and that no other elements may be present. By "consisting essentially of," it is meant to include any elements listed after the phrase, and is not limited to other elements that do not interfere with or contribute to the activity or effect specified in the disclosure for the listed elements. Thus, the phrase "consisting essentially of means that the listed elements are required or mandatory, but that other elements are optional and may or may not be present, depending on whether they substantially affect the activity or effect of the listed elements. Any element or combination of elements recited in this specification in an open-ended language (e.g., including and derived from) is considered to be encompassed in a closed-ended language (e.g., consisting of and derived from).

The words "preferred" and "preferably" refer to embodiments of the disclosure that may provide certain benefits under certain circumstances. However, other claims may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred claims does not imply that other claims are not useful, and is not intended to exclude other claims from the scope of the disclosure.

In this application, terms such as "a," "an," "the," and "said" are not intended to refer to only a single entity, but include the general class of specific examples that may be used for illustration. The terms "a", "an", "the" and "the" are used interchangeably with the term "at least one". The phrase "at least one of (and" including ") of the following list refers to any one of the items in the list and any combination of two or more of the items in the list.

As used herein, the term "or" is generally employed in its ordinary sense, including "and/or" unless the context clearly dictates otherwise.

The term "and/or" means one or all of the listed elements or a combination of any two or more of the listed elements.

In addition, all numerical values herein are assumed to be modified by the term "about" and in certain embodiments are preferably modified by the term "exactly. As used herein, with respect to a measured quantity, the term "about" refers to a deviation in the measured quantity that is commensurate with the objective of the measurement and the accuracy of the measurement equipment used, as would be expected by a skilled artisan taking the measurement with some degree of care. Herein, "at most" a number (e.g., at most 50) includes the number (e.g., 50).

Also herein, the recitations of numerical ranges by endpoints include all numbers subsumed within that range and the endpoints (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4,5, etc.).

As used herein, the term "room temperature" refers to a temperature of 20 ℃ to 25 ℃ or 22 ℃ to 25 ℃.

The term "in a range" or "within a range" (and the like) includes the end-value of the range.

Groupings of alternative elements or embodiments disclosed herein are not to be construed as limiting. Each group member may be referred to and claimed individually or in any combination with other members of the group or other elements found therein. It is contemplated that one or more members of a group may be included in the group or deleted from the group for convenience and/or patentability reasons. In the event of any such additions or deletions, the specification is considered herein to contain a modified group, thereby satisfying the written description of all markush groups used in the appended claims.

Reference throughout this specification to "one embodiment," "an embodiment," "certain embodiments," or "some embodiments," or the like, means that a particular feature, configuration, composition, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of such phrases or in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, configurations, compositions, or characteristics may be combined in any suitable manner in one or more embodiments.

The above summary of the present disclosure is not intended to describe each disclosed embodiment or every implementation of the present disclosure. The following description more particularly exemplifies illustrative embodiments. Throughout this application, guidance is provided through lists of examples, which can be used in various combinations. In each case, the lists cited are intended as representative groups only and are not to be construed as exclusive lists. Thus, the scope of the present disclosure should not be limited to the particular illustrative structures described herein, but rather extends at least to structures described by the language of the claims and the equivalents of those structures. Any elements that are positively recited in the specification as alternatives can be explicitly included in or excluded from the claims in any combination as desired. While various theories and possible mechanisms may have been discussed herein, such discussion should not be used in any way to limit the subject matter which may be claimed.

Drawings

FIG. 1 is a schematic representation of electrical hardware including a dielectric fluid containing a perfluorinated 1-alkoxy propene compound according to the present disclosure.

Detailed Description

In electrical devices such as capacitors, dielectric fluids are often used to replace air due to their low dielectric constant (K) and high Dielectric Strength (DS). Some capacitors of this type include alternating layers of metal foil conductor and solid dielectric sheets of paper or polymer film. Other capacitors are constructed by wrapping metal foil conductor(s) and dielectric film(s) concentrically around a central core. This latter type of capacitor is referred to as a "film-wound" capacitor. Because of their low dielectric constant and high dielectric strength, dielectric fluids are often used to impregnate dielectric films. Such dielectric fluids allow more energy to be stored within the capacitor (higher capacitance) than air-filled or other gas-filled electrical devices.

In exemplary embodiments, the present disclosure relates to the use of perfluorinated 1-alkoxy propene compounds represented by the following general formula (I), which may be in the trans or cis configuration:

R_fO-CF＝CFCF₃

I

wherein R is_fIs CF₃-or CF₃CF₂As a dielectric fluid.

In some embodiments, the compound of formula (I) (CF)₃-O-CF＝CF-CF₃And CF₃CF₂-O-CF＝CF-CF₃) In the gas phase, in the liquid phase or in a combination thereof under the operating conditions of the plant in which they are contained. The dielectric fluids of the present disclosure may be used in electrical devices.

In certain embodiments, mixtures of compounds of formula (I) are used. In certain embodiments of the mixture, at least a portion of the compound is in the trans configuration and at least a portion of the compound is in the cis configuration. At CF₃-O-CF＝CF-CF₃In certain embodiments, at least a portion is in the cis configuration and at least a portion is in the trans configuration. At CF₃CF₂-O-CF＝CF-CF₃In certain embodiments, at least a portion is in the cis configuration and at least a portion is in the trans configuration.

The perfluorinated 1-alkoxypropylene compound of formula (I) may be prepared by the reaction of a Lewis acid with a perfluoroalkyl ether compound represented by the following general formula (II):

wherein Rf is as described for formula (I). Examples of Lewis acids include TiF₄、ZrF₄、NbF₅、TaF₅、BF₃、SbF₅ACF (aluminum chlorofluoride), SbCl₂F₃、SbCl₄F、HSbF₆、SbCl₅、AlCl₃And mixtures thereof. Exemplary strips of such preparation reactionsThe elements are shown in the examples section.

The present disclosure also provides an electrical device comprising a dielectric fluid comprising a perfluorinated 1-alkoxy propene compound represented by formula (I). In some embodiments, the present disclosure also provides a dielectric fluid comprising a mixture of one or more perfluorinated 1-alkoxypropene compounds represented by formula (I) and one or more secondary dielectric gases.

The perfluorinated 1-alkoxy propylene compounds represented by formula (I) of the present disclosure advantageously have a wide operating temperature and pressure range, are thermally and chemically stable, and have a SF above SF at a given partial pressure₆Has a dielectric strength and a heat transfer efficiency lower than SF₆Global Warming Potential (GWP). In addition, the perfluorinated 1-alkoxy propene compounds represented by formula (I) of the present disclosure have surprisingly low toxicity. The perfluorinated 1-alkoxypropene compounds represented by formula (I) typically have a dielectric strength of at least 50kV/in (kilovolts/inch) at an operating pressure of 20kPa (kilopascals) and at an operating temperature of the electrical devices containing them.

As used herein, the global warming potential "GWP" is a relative measure of the warming potential of a compound based on the structure of the compound. The GWP of a compound defined by the inter-government climate change committee (IPCC) in 1990 and updated in 2007 was calculated as being within the specified integration time range (ITH) relative to the release of 1 kg of CO₂The resulting warming, 1 kg of compound released.

In this equation, a is the increased radiation forcing per unit mass of compound in the atmosphere (change in radiation flux through the atmosphere due to IR absorption by the compound), C is the atmospheric concentration of the compound, τ is the atmospheric lifetime of the compound, t is time, and i is the compound of interest.

The generally accepted ITH is 100 years, which represents both short-term effects (20 years) and long-term effects (500 years or more)) A compromise between. The concentration of organic compound i in the atmosphere is assumed to follow quasi-first order kinetics (i.e. exponential decay). CO in the same time interval₂Concentration by exchange and removal of CO from the atmosphere₂More complex model (Bern carbon cycle model).

Due to degradation in a lower atmospheric environment, with SF₆In contrast, the perfluorinated 1-alkoxypropene compounds represented by formula (I) have shorter lifetimes and contribute less to global warming. The perfluorinated 1-alkoxypropenes represented by formula (I) may have a GWP of less than 500, less than 250, less than 100, less than 50 or even less than 20. In addition to the dielectric performance characteristics and their relatively low toxicity, the relatively low GWP of perfluorinated 1-alkoxypropene compounds represented by formula (I) make them very suitable for use as dielectric fluids.

Advantageously, the dielectric fluids of the present disclosure have a high dielectric strength, also described as a high breakdown voltage. In general, "breakdown voltage" (at a particular frequency) refers to the voltage applied to a fluid that causes significant damage to the fluid dielectric, thereby conducting current through the fluid. Thus, the fluid dielectric of the present disclosure may function at high voltages. The fluid dielectric may also exhibit a low power dissipation factor, i.e., the amount of electrical energy lost as heat from an electrical device such as a capacitor.

In some embodiments, the perfluorinated 1-alkoxypropene compounds of formula (I), when used as liquid dielectrics, have a liquid phase range that encompasses the operating temperature range of the electrical device in which either or both are used as components.

In some embodiments, the perfluorinated 1-alkoxypropene compound represented by formula (I) has a gas phase range that encompasses the operating temperature range of the electrical device in which it is used as a dielectric component. For example, these compounds have a boiling point in the range of 0 ℃ to 35 ℃. Many electrical devices such as capacitors, transformers, circuit breakers and gas insulated transmission lines can operate at temperatures of 30 ℃ and higher.

The perfluorinated 1-alkoxypropene compounds represented by formula (I) have a vapor pressure of at least 20kPa at the operating temperature of the electrical devices containing them.

Further, the perfluorinated 1-alkoxypropene compound represented by formula (I) has a dielectric strength of at least 50 kV/inch at an operating pressure in an electrical device of 20 kPa. More specifically, the perfluorinated 1-alkoxy propene compound represented by formula (I) has a dielectric strength of at least 80 kV/inch at the operating temperature and pressure of the device.

In some embodiments, the perfluorinated 1-alkoxy propene compounds represented by formula (I) may be combined with one or more secondary dielectric gases having a higher vapor pressure. In some embodiments, the one or more secondary dielectric gases are used in an amount such that the vapor pressure is at least 70kPa at 25 ℃ or at the operating temperature of the electrical device.

In some embodiments, the perfluorinated 1-alkoxy propene compounds represented by formula (I) may be combined with one or more secondary dielectric gases having a lower vapor pressure.

In some embodiments, the perfluorinated 1-alkoxypropene compound represented by formula (I) may be combined with one or more secondary dielectric gases that comprise 50 mole% or more of the mixture.

These secondary dielectric gases typically have boiling points below 0 ℃, zero ozone depletion potential, and global warming potential below SF₆Is (about 22,200), and is chemically and thermally stable. They may be condensable or non-condensable gases. Combinations of such secondary dielectric gases may be used as desired.

In some embodiments, the secondary dielectric gas comprises one or more fluorinated organic compounds. Such fluorinated organic compounds include, for example: perfluoroalkanes such as those having 1 to 4 carbon atoms; fluorinated olefins, such as CF₃CH＝CHCF₃、CF₃CH＝CHCl、CF₃CF＝CFCF₃、CF₃CF＝CH₂、CF₃CH＝CFH、CF₃CF＝CFH、CF₃CH＝CF₂Or HCF₂CF＝CF₂(ii) a Fluorinated ketones, such as CF₃C(O)CF(CF₃)₂、CF₃CF₂C(O)CF(CF₃)₂、CF₃CF₂CF₂C(O)CF(CF₃)₂Or (CF)₃)₂CFC(O)CF(CF₃)₂(ii) a Fluorinated nitriles, such as (CF)₃)₂CFCN; fluorinated nitroalkanes, such as CF₃CF₂NO₂(ii) a Fluorinated diketones, such as CF₃C(O)C(O)CF₃(ii) a And fluorinated oxiranes, such as described in WO 2012/102915(3M company).

In some embodiments, the secondary dielectric gas comprises a gas selected from the group consisting of nitrogen, carbon dioxide, nitrous oxide (N)₂O), helium, argon, oxygen, and combinations thereof (e.g., air).

In some embodiments of the dielectric fluids described herein, perfluorinated 1-alkoxy propylene compounds represented by formula (I) may be reacted with SF₆Combined such that the mixture of dielectric fluids has a lower SF than the individual₆The global warming potential of.

In some embodiments, the ratio of the vapor pressure of the secondary dielectric gas to the perfluorinated 1-alkoxypropene compound represented by formula (I) is at least 2.5: 1, specifically at least 5: 1, and more specifically at least about 10: 1.

The perfluorinated 1-alkoxy propene compounds represented by formula (I) can be used in the gas phase for electrical insulation and for quenching and current interruption devices used in the transmission and distribution of electrical energy.

The main types of electrical devices in which the gas of the present disclosure can be used include gas-insulated circuit breakers, current interruption equipment including switchgear, gas-insulated transmission lines, gas-insulated transformers and gas-insulated substations. Such gas-insulated devices are a major component of power transmission and distribution systems worldwide.

In some embodiments, the present disclosure provides an electrical device, such as a capacitor, that includes metal electrodes spaced apart from one another such that a gaseous dielectric fills the space between the electrodes. The interior space of the electrical device may also comprise a reservoir of one or more perfluorinated 1-alkoxypropene compounds of formula (I) in liquid form. In certain embodiments, the reservoir comprises one or more perfluorinated 1-alkoxypropene compounds of formula (I) in liquid form in equilibrium with one or more perfluorinated 1-alkoxypropene compounds represented by formula (I) in gas form. Thus, the reservoir may replenish any loss of gaseous perfluorinated 1-alkoxypropene compound of formula (I).

For circuit breakers, the thermal conductivity and dielectric strength of such gases, as well as thermal recovery and dielectric recovery (short time constants for increasing resistivity), can provide high interrupting capability. These properties enable the gas to transition rapidly between the conductive (arc plasma) and dielectric states of the arc and to withstand a rise in recovery voltage.

For gas-insulated transformers, in addition to the dielectric properties, the heat transfer properties and compatibility with existing devices make the dielectric fluids of the present disclosure desirable media for use in such electrical equipment.

The perfluorinated 1-alkoxy propylene compounds represented by formula (I) have significant advantages over oil insulation, including not having fire safety issues or environmental compatibility issues, and having high reliability, less maintenance, long service life, low toxicity, ease of handling, and reduced equipment weight.

For gas-insulated power transmission lines, the dielectric strength of the gaseous perfluorinated 1-alkoxypropenoic compounds of formula (I) under industrial conditions can be significant, especially the behavior of gaseous dielectrics under metal particle contamination, switching pulses and lightning pulses, and fast transient electrical stresses. The gaseous perfluorinated 1-alkoxy propene compounds of formula (I) may also have a high heat transfer efficiency from the conductor to the housing and may be stable for a long period of time (e.g. 40 years). These gas insulated transmission lines can provide significant advantages including, but not limited to, cost efficiency, high load capacity, low losses, availability at all rated voltages, no fire risk, reliability, and compact alternatives to overhead high voltage transmission lines in populated areas (which avoid the public concern of overhead transmission lines).

For gas insulated substations, the dielectric fluid of the present disclosure may be used to insulate the entire substation (circuit breakers, disconnectors, earthing switches, busbars, transformers, etc., which are interconnected), and therefore all of the above properties of the dielectric gas are important.

In some embodiments, the gaseous dielectric may be present in the electrical device as a gas itself, or as a gas in equilibrium with a liquid. In these embodiments, the liquid phase may serve as a reservoir for additional dielectric gas.

The use of perfluorinated 1-alkoxy propene compounds of formula (I) as dielectric fluids is shown in the general electrical device of fig. 1. Figure 1 shows an apparatus comprising a tank or pressure vessel 2, the tank or pressure vessel 2 comprising electrical hardware 3, such as switches, interrupters or coils of transformers, and at least one gaseous perfluorinated 1-alkoxypropene compound of formula (I). Optionally, the reservoir of gaseous perfluorinated 1-alkoxy propene compound of formula (I) is in equilibrium with the reservoir of liquid perfluorinated 1-alkoxy propene compound of formula (I).

In another aspect, an electrical device is provided, comprising as an insulating material a dielectric liquid comprising at least one perfluorinated 1-alkoxy propene compound of formula (I). The dielectric fluids of the present disclosure may be used in a variety of other applications in which dielectric fluids are used. Examples of such other applications are described in U.S. patents 4,899,249(Reilly et al) and 3,184,533(Eiseman, Jr.); and british patent 1242180 (Siemens).