Colloidal insulating and cooling fluid

 

Use: for isolation and/or cooling electromagnetic devices, including power transformers. The technical result is to secure increasing values of voltage pulse breakdown. In embodiments of the invention proposed colloidal fluids, which contain a carrier fluid in the form of oil and dispersed phase of non-metallic particles which are magnetic, and colloidal fluid has a saturation magnetization of from 1 to 20 Gauss. The proposed arrangement provides increased circulation of liquid around the cooled transformer. 4 C. and 20 C.p. f-crystals, 1 Il., 3 table.

The present invention relates to new colloidal liquids. More specifically, the present invention relates to the creation of new colloidal liquids and their use as insulation and/or cooling electromagnetic devices.

Liquid insulation in an electromagnetic device, such as a power transformer, is exposed to stresses of various types: - voltage alternating current (AC) having a wide range of amplitudes and frequencies, and pulse voltages (mainly short-term stress constant is atragene), generated electric fields specific voltage, is often the most important property of this exclusion. This determines the possibility of using specific liquid as insulation in the transformer (or other electromagnetic device that uses high voltage) with a specified range (class) stresses. The choice of insulation is important because it can determine the structure of all the main elements of the device.

Usually the highest load in the liquid insulation are due to surge voltage (lightning). When the amount of liquid insulation is exposed to the critical electrostatic discharge (mechanical stress in the dielectric from the effects of electrical voltage) generated by the increase in the peak value of the pulse voltage, the breakdown can happen isolation.

To maximize the efficiency of the transmission and distribution of electrical energy, it is often necessary to use in electromagnetic devices high current density and high voltage AC. The use of large currents leads to the increased secretion of warmth, while the application of high voltage is gitogo device. The increase in the allocation of heat limits the maximum current that can safely flow through conductive (conductive) elements of the electromagnetic device, and also increases the cost of transmission, distribution and end-use electric energy due to the increasing demand in conductive materials (due to the increase of the consumption of such materials). This also leads to an increase in the size and weight of this electromagnetic device. High electric field strength also limits the voltage drop per unit of space within the electromagnetic device, which leads to an increase in the cost of transmitting energy from its production to the end user. Moreover, to compensate for the high electric field is often necessary to increase the intervals between the turns of the winding, filled with an insulating liquid such as transformer oil, thereby further increasing the size and cost of the transformer.

As the electric current generates both heat and electric field intensity, it is important that the electrical insulation is continuously performed two different functions: (a) prevented proteini is Motoc and magnetic core to the outer walls of the device, which should be cool. Dielectric properties of liquid insulation are the most critical, as they are responsible for the operation of high voltage electromagnetic device, and an electrostatic voltage of insulating liquids cannot be broken. As a result, virtually all known liquid insulation are mainly high electrostatic voltage, low conductivity, and high levels of purity; it is possible to believe that this last property is necessary to achieve the desired electrostatic voltage. However, the known system with liquid insulation also have low thermal conductivity, which prevents efficient heat transfer by conduction. Instead, these electromagnetic devices typically use arhimedova convection resulting from the expansion of liquid insulation, such as transformer oil, when heated to high temperatures that develop arhimedova forces that raise hotter (and less dense) oil and put down cold (and thicker) oil. This creates a thermal convection and possible heat transfer from the windings to the external walls and requires to have special channels (pipes) inside the windings and magnetic core, so that the oil can flow through the most heated internal sections of the components that emit heat. The application of heat using a rather inefficient mechanism Archimedean convection leads to an increase in the overall dimensions of the device and increase the cost by reducing the number of conductive or magnetic material per unit volume.

Known liquid insulation shall exercise their functions in a limited range of currents, voltages and environmental conditions, which determines the nominal power of the electromagnetic device. There is a need to expand these limits so that you can pass through the device more power, i.e. higher voltage or higher current without compromising its safety and reliability, or to transmit the same power, but with the help of a smaller size and cheaper devices. The present invention is directed to solving the above and other important tasks.

The present invention partially has to do with colloidal liquids. In accordance with dederit (a) approximately from to 98 to 99.99% by volume of the carrier liquid and (b) approximately from 0.01 to 2% by volume of non-metallic particles, moreover, the colloidal fluid has a saturation magnetization of approximately less than 50 Gauss.

In accordance with another embodiment of the present invention proposed a stable colloidal liquid, which contains (a) a liquid carrier, and (b) non-metallic particles, and colloidal fluid has a saturation magnetization of approximately less than 50 Gauss.

In accordance with another embodiment of the present invention, a method for preparing a colloidal fluid with a saturation magnetization of approximately less than 50 Gauss. The method comprises (a) preparing a carrier fluid and (b) a combination of non-metallic particles from the carrier fluid.

In accordance with another embodiment of the present invention proposed an electromagnetic device. This device includes (a) means for creating an electromagnetic field and heat and (b) stable colloidal fluid that is in contact with the device. Colloidal liquid contains (i) a liquid carrier, and (ii) non-metallic particles, and the specified colloidal fluid has a saturation magnetization of approximately less than 50 Gauss.

In accordance with another varianta, which generates an external magnetic field and warmth. This method provides for the establishment of contact (communication) devices with a stable colloidal liquid, which contains (a) a liquid carrier, and (b) non-metallic particles. Colloidal fluid has a saturation magnetization in the range of greater than zero and approximately less than 50 Gauss.

These and other features of the invention will be more apparent from the appended claims and from the subsequent detailed description, given as an example having no limiting character and described with reference to the accompanying drawings.

The drawing schematically shows a transformer having a cooling system in accordance with the present invention.

The present invention is directed in part on the creation of new colloidal fluids intended for use, for example, in electromagnetic devices. Used here, the term “colloid” refers to the condition division (split) of the substance (matter), which can contain a single large molecules or aggregation (clusters) of small molecules. Inside of a colloidal solution (colloid) particles of ultramicroscopic size, which Castelen, the dispersion medium or the external phase. The size of the particles present in colloidal solutions in accordance with the present invention may vary depending, for example, from the used particles from a specific application, etc., Generally speaking, the particle size predominantly lies in the range approximately from 1 to 100 nm with all combinations and subcombinations particles. Thus, colloidal solutions in accordance with the present invention in General can be called “nanoidustry”. In accordance with some of the options for implementation of the present invention the particles in colloidal solutions can be magnetic. Used here, the term “magnetic” refers to the properties of substances which, under certain circumstances attract or repel each other. An example of a colloid, which contains magnetic particles, is “(ferro)magnetic fluid”. Described here, the magnetic fluid can respond to the applied magnetic field, because the liquid has magnetic characteristics. In accordance with certain other preferred variants of the present invention colloids contain particles that are non-magnetic. Used here mellody in accordance with the present invention mainly allow to solve the above mentioned three fundamental problems, which can limit the power distributed in a unit volume (or weight) of the device. In particular, the colloids in accordance with the present invention is mainly characterized by one or more of the following properties: (a) higher voltage partial discharge, which allows you to have shorter distances between conductive elements of the device due to the expansion (increase) boundaries for short-term fluctuations of the alternating current, (b) high impulse dielectric strength, allowing you to have in the transformer smaller gaps between charged parts (components), as well as to provide increased reliability in high-voltage pulsed emission (throws), and (C) increased heat capacity is proportional to the intensity of the magnetic field, to effectively transfer heat from the internal space of the winding, where the magnetic field is strongest and where the most critical conditions of heat exchange.

Generally speaking, new colloids in accordance with the present invention can be prepared, for example, by combining the particles with the carrier fluid. In accordance with the preferred method of implementation, the crust is a high concentration of particles, with conventional liquid insulation, such as a conventional transformer oil, to obtain nanoalberta. Next are discussed in more detail further methods of preparation of colloids. In accordance with a preferred variant implementation of the present invention nanosight may have dielectric properties. These dielectric nanosight can be mainly non-magnetic or they may have magnetized (magnetic) properties. Typical dielectric nanoidustry in accordance with the present invention are the (ferro)magnetic fluid. The composition described here nanoalberta can be selected to obtain the desired properties, which depend, for example, on the particular application. For example, nanosight can be prepared first of all to enhance the dielectric strength of the insulation. The increase in the volume concentration of particles can provide a corresponding increase in saturation magnetization, which leads to both an increase in the dielectric strength of insulation and to improve heat transfer characteristics of nanosight. The composition of the colloids in the first place, can be chosen to provide the desired heat transfer the resistance (which are determined by the volume percentage of the magnetic particles, their average size and frequency distribution, as well as some specifics of manufacturing (ferro)magnetic fluid) on the dielectric strength of the magnetic fluid in terms of AC and DC voltages, as well as its cooling capacity has been examined by the testing laboratory and industrial transformers. Preparation of new colloidal isolating (insulating) liquids was carried out in such a way that parameters such as the start voltage partial discharge (PD), heat capacity, voltage, pulse breakdown, all correlated with two parameters, easy to measure after cooking magnetic colloidal fluid, namely the saturation magnetization (Ms), which is described and claimed here applications can be zero (for non-magnetic colloids) or may vary approximately from 0, 5 to 50 Gauss, and electrical resistivity (R), which can vary from approximately 109to more than 1013Om-see Valid values for these two parameters depend on the specific combination of insulating properties and the cooling capacity required for a given transformer.

The electrical resistivity and is therefore particularly useful for use as insulating fluids for electromagnetic devices including for transformer devices. In particular, the colloids in accordance with the present invention can provide a substantial increase in the minimum values of the voltage impulse breakdown compared with the minimum values of the voltage impulse breakdown for most previously known insulating liquids. In accordance with the preferred options colloids in accordance with the present invention provide an increase in the values of the voltage pulse break of at least approximately 10%, with an increase of more than approximately 10% is preferable and may be, for example, about 15%. In a more preferred embodiment, the colloids in accordance with the present invention provide an increase in the values of the voltage impulse breakdown approximately more than 15%, for example, approximately 20%, with an increase of more than about 20% is preferred and may be, for example, about 25%. In an even more preferred embodiment, the colloids in accordance with the present invention provide an increase in the values of the voltage impulse breakdown approximately more than 25%, for example, approximately n the example, about 35%. In an even more preferred embodiment, the colloids in accordance with the present invention provide an increase in the values of the voltage impulse breakdown approximately more than 35%, for example approximately 40%, with an increase of more than approximately 40% is preferable and may be, for example, about 45%. In an even more preferred embodiment, the colloids in accordance with the present invention provide an increase in the values of the voltage impulse breakdown approximately more than 45%, for example approximately 50%, with an increase of more than approximately 50% is still more preferred.

In addition to the above-mentioned desirable insulating properties in accordance with a preferred variant of the present invention colloids can possess in the highest degree preferred properties of heat transfer. Therefore colloids in accordance with the present invention can be used suitably, for example, as a cooling fluid for cooling electromagnetic devices, including large power transformers that operate at elevated temperatures. As we all know 176.gif">With and typically have a maximum operating temperature of about 110With temperatures so-called hot spots approximately 130C. the Observed temperature rise when using colloidal insulating liquids in accordance with the present invention, which are used as coolants may be significantly less than the observed increase in temperature for most of the previously known insulating and/or cooling liquids. In an advantageous variation temperature rise in the use of colloids in accordance with the present invention mainly reduced at least approximately 1%, with the decrease of temperature increase by more than 1% is preferred and is, for example, about 5%. In a more preferred embodiment, the temperature rise in the use of colloids in accordance with the present invention mainly reduced by more than about 5%, for example approximately 10%, with the decrease of temperature increase is more than 10% is preferred and is, for example, about 15%.

Not wanting to associate themselves with any of those who STV cooling in accordance with the variants of the present invention may be caused, at least partially, the predominant use of the magnetic properties. In this regard (and as discussed in more detail below) colloids in accordance with the present invention have a saturation magnetization of approximately 50 Gauss (mostly less than approximately 50 Gauss and, in some preferential embodiments, more than 0 and less than approximately 50 Gauss). Thus, in the case of, for example, colloids, which contain magnetic particles, the magnetic field gradients that can be created in electromagnetic devices that can attract and captivate the colloids in the direction of the regions of the device where the magnetic field is strongest, for example in the direction of the windings. This advantageously enhances the convection cycle, which is due to two forces: magnetic forces and gravity forces. However, in some designs of the transformers, including, for example, in transformers with disc windings, the magnetic forces created mainly horizontal convection, which is perpendicular to arhimedova component and undesirable impact on Archimedes flow of coolant. This horizontal convection can be reduced by limiting namini with the present invention mainly is chosen so that to provide the preferred radial or angular convection inside the unit coil/core and to provide the best cooling effects, for example, by preventing the formation of undesirable hot spots. At the same time in areas outside of the unit coil/core, where the sharp decrease of the magnetic field, Archimedean convection may prevail, which preserves the normal trajectory (i.e. vertical) circulation.

Colloids in accordance with the present invention are highly stable. Used here, the term “stable” means that the colloids are mainly or completely are resistant to degradation, including, for example, and to chemical degradation of the dispersed phase and/or carrier phase, and the phase separation of the dispersed phase and carrier phase, when exposed to various temperatures, including high temperatures, which may be associated with the operation of electromagnetic devices such as power transformers, mainly for long periods of time. Thus, the colloids in accordance with the present invention are particularly suitable for use, for example, as isomet very long life. In the preferred form colloids in accordance with the present invention mainly has an electrical resistivity of at least about 109Ohm-cm, and an electric resistivity of more than 109Ohm-cm is preferred. In a more preferred embodiment, the colloids in accordance with the present invention mainly has an electrical resistivity in excess of 109Ohm-cm, which is approximately more than 1013Om-see As previously discussed, the colloids in accordance with the present invention are also highly favorable heat transfer characteristics. Thus, described herein colloids can be successfully used as refrigerants (halogenosilanes) for electromagnetic devices, including electromagnetic devices that operate at high power levels and can create significantly elevated operating temperatures, such as power transformers.

A wide variety of materials can be used in the colloids in accordance with the present invention, for example, as the dispersed phase and/or carrier phase. Use colloids konkretnogo resistivity, etc., and on the desired application. In the preferred form of the dispersed phase and the phase of the carrier is chosen so that the colloids in accordance with the present invention have a saturation magnetization (Ms) approximately not more than 50 Gauss, and mostly less than 50 Gauss, for example approximately from 0 to less than 50 Gauss, finding in this range all combinations and subcombinations. In the case of colloids made from non-magnetic particles, these colloids can have a saturation magnetization of about 0. In the case of colloids prepared from particles having magnetic properties, these colloids can have a saturation magnetization in the range of approximately greater than 0 to less than 50 Gauss. It was found that particularly favorable effects of cooling give colloids having a saturation magnetization of approximately from 0.5 to less than 50 Gauss, and the optimal cooling is observed in the magnetization and the saturation of approximately 20 to 40 Gauss. It was found that particularly favorable dielectric strength observed in the case when the colloids in accordance with the present invention have a saturation magnetization of approximately from 0.1 to 5 G, and the optimal dielektricheskii the temporal obtain the desired cooling properties and dielectric strength colloids in accordance with the present invention should have a saturation magnetization of approximately from 1 to 20 GS, moreover, when the magnetization and the saturation of approximately from 5 to 20 Gauss obtain the optimum combination of properties.

In accordance with a preferred variant implementation of the present invention, the phase of the carrier is primarily liquid, which in itself is stable and which creates a desirable and stable environment (environment) to the dispersed phase. Also preferably, the phase of the carrier had a low dielectric constant, mainly approximately less than 3 units. Also preferably, the phase of the carrier possessed high levels of electrical resistivity, which increases the electrical resistivity of colloids in accordance with the present invention, as discussed here previously. The viscosity of the carrier phase may be desired, therefore, to provide the desired stability of colloids in accordance with the present invention, and preferred to provide convection cooling, which is also discussed here previously.

In accordance with a preferred variant implementation of the present invention in the colloids in accordance with the present invention is any of the oils, which is usually used for cooling large power transformers, such as, for example, various forms of oil (a mixture of liquid hydrocarbons), including high molecular weight, synthetic hydrocarbons and silicones. Oils that are particularly suitable for use as carrier phase in the colloids in accordance with the present invention, represent transformer mineral oil available on the market with the trade name UNIVOLTthat can be purchased on the company Exxon Corporation (St. Paul, MN, USA). For use as a carrier phase in the colloids in accordance with the present invention may be suitable, and other materials known to experts in the field, armed contained in the present invention the information.

As mentioned earlier, colloidal fluid in accordance with the present invention also preferably contain a disperse phase, mainly in the form of particles. Similarly discussed here earlier phase of the carrier, with a wide variety of materials can be used in the colloids in accordance with the present invention as the dispersed phase. In accordance with a preferred paravisini electric strength of the alternating current may be provided in the case, when the dispersed phase contains a non-metallic material. Used here, the term “non-metallic” refers to a significant (and complete) the absence of metal properties and/or characteristics. Examples include non-metallic materials that can be used as the dispersed phase, you can specify organic materials (such as, for example, polymeric materials, inorganic materials (such as aerosols) and some elements, such as elemental carbon. Among these non-metallic materials are preferred inorganic materials, among which the most preferred are metal oxides.

In accordance with some preferred variants of implementation of the present invention dispersed phase produced from materials that are magnetic (i.e. from materials that have intrinsic magnetic dipole moment), and preferred are materials that are both magnetic and non-metallic, as it was discovered that this can be obtained simultaneously high electrical durability AC and preferred properties klaeden approximately 200C. In particularly preferred embodiments, the dispersed phase contains magnetic inorganic material, and most preferred are magnetic metal oxides. Among the metal oxides are preferred, for example, iron oxides (such as, for example, FeO, Fe2About3and Fe3O4the oxides of zinc (such as, for example, ZnO), cobalt (such as, for example, COO), manganese (such as, for example, IGOs, Me3O4and MP2O3), titanium (such as, for example, Tio2and Ti2About3), copper (such as, for example, C2O), Nickel (such as, for example, NiO and Ni2O3) and chromium (such as, for example, CR2O3). Preferred are also mixtures of metal oxides, including, for example, oxides of iron and cobalt (such as, for example, Fe2CoO4), iron, manganese and zinc (such as, for example, MnxZn(1-x)Fe2O4where x can take values from approximately 0.4 to 0.8), as well as iron, cobalt and zinc (such as, for example, CoxZn(1-x)Fe2O4where x can take values from approximately 0.2 to 0.6). Particularly preferred among the metal oxides are oxides of iron. In the site is mainly on temperature. From this point of view oxides MnxZn(1-x)and the iron oxides are preferable, and oxides of MnxZn(1-x)especially well suited for use in the most severe conditions (such as, for example, existing in traction transformers), and iron oxides are particularly well suited for use in conventional power and distribution transformers.

In accordance with some preferred variants of implementation of the present invention dispersed phase produced from materials which are non-magnetic. Examples of preferred non-magnetic materials, you can specify polymeric materials and inorganic aerosols. Among the polymeric materials are preferred fluorinated polymers, which include, for example, poly (tetrafluoroethylene), which can be purchased at the DuPont Chemical Co. (Wilmington, DE, USA) under the name TEFLON.

Other materials that can be successfully used as the dispersed phase in the colloids in accordance with the present invention, can easily be found by experts in the field, armed contained in the present invention the information.

Material cotrimoxazole has the form of particles. Size dispersed in colloids particles can vary and depends, for example, of the specific type of the dispersed phase and carrier phase, and also on the desired application. However, the particle size is chosen in the preferred range of the particles. In this regard, it was found that the particle size can affect the cooling properties and electrical resistivity of the colloid. For example, the use of small particles can lead, depending on the chemical components of particles to obtain colloids with low electrical resistivity, which can lead to undesirable high dielectric losses. On the contrary, the use of large particles may result depending on the chemical components of particles to obtain colloids with low stability properties, especially at elevated temperatures. As noted here previously, with the preferred particle size range is approximately from 1 to 100 nm, taking into account all combinations and subcombinations. Preferably the average particle size lies in the range approximately from 5 to 20 nm, and the average particle size greater than 5 and less than 20 nm, for example of 15 nm is more preferred. Bolevan 90% of the particles larger than 7 nm is most preferable.

The concentration of the dispersed phase in colloidal liquids in accordance with the present invention may vary and depends, for example, on the particular species used in the dispersed phase and carrier phase from the desired use of the colloid, etc., At the request of the colloid may initially have a higher concentration of the dispersed phase. Then these concentrated colloids can be diluted, for example, to achieve the preferred concentration, which is discussed here in more detail below. In this way the colloids in accordance with the present invention may be communicated to an advantageous flexibility (flexibility), as concentrations may be specified by the end user depending on the particular application. In this connection provides for dilution, for example, at the place of intended use, such as the place of manufacture and/or use of the power transformer. The original preparation of colloids in concentrated form can be used to reduce the amount of colloidal fluids, which need to be transported to the desired place of use. This allows you to facilitate transport of colloids, for example, accounts for economic benefits.

Generally speaking, the dispersed phase can be entered in the colloids in accordance with the present invention at concentrations, which mainly lie in the range from approximately 0% by volume, for example from 0.01% by volume to approximately 2% by volume being in the range of all combinations and subcombinations. For colloids with the dispersed phase, which contains nonmagnetic particles, the concentration of the dispersed phase is preferably approximately from 0.01% by volume to approximately 0.5% by volume, and concentration of approximately from 0.05 to 0.3% by volume are preferred. For colloids with the dispersed phase, which contains magnetic particles, the concentration of the dispersed phase is preferably approximately from 0.01% by volume to less than 2% by volume, and concentration of approximately from 0.02 to 1% by volume are preferred.

As can be easily understood by experts in the field, armed contained in the present invention, the concentration of the carrier phase in the here described colloids may vary and depends, for example, from the used concentration of the dispersed phase, as discussed here previously. Generally speaking, the number of getcoordinates in this range all combinations and subcombinations. For colloids with the dispersed phase, which contains nonmagnetic particles, the concentration of the carrier liquid can mainly be about 99.99% by volume to approximately 99.5 per cent by volume, and concentration from approximately 99.95% of up to 99.7% by volume are preferred. For colloids with the dispersed phase, which contains magnetic particles, the concentration of the carrier liquid can mainly be about 99.99% by volume to more than 99,8% by volume, and concentration of approximately from of 99.98 to 99% by volume are preferred.

Also described here is the dispersed phase and carrier phase, colloids in accordance with the present invention can optionally contain other materials additives (additives), including, for example, stabilizing materials, such as, for example, surfactants, dispersants, thickeners, viscosity modifiers, antioxidants, etc. In an advantageous options optional extension material contains a surfactant. Mainly surface-active substance comes into contact with particles or substantially (including completely) covers the particles in the colloid. If DeMint used colloids in accordance with the present invention. Surfactant can be anionic, cationic or non-ionic depending on, for example, from concrete used in the dispersed phase and carrier phase, and also on the desired application. As examples of anionic surfactants can be specified (bold) compounds with long chain, which contain carboxyl groups, succinate groups, phosphate groups or sulphonate groups. As examples of cationic surfactants can be specified, for example, compounds with long chain that contain protonated or Quaternary ammonium group. As examples of nonionic surface-active substances, you can specify alcohols and polyoxyalkylene polymers. Except as specified here above surfactants, colloids in accordance with the present invention can be used, and other surface-active substances, and also other desirable optional additional materials that can be easily understood by experts in the field, armed contained in the present invention the information.

The concentration of the optional additional materials that can be used colloids in accordance with the present izobretatelnee phase and/or carrier phase. Mainly additional material additive may be used at a concentration that enhances the desirable characteristics of colloids, such as, for example, stability, cooling capacity, antioxidant properties and/or insulating properties. In an advantageous options optional extension material can be used at concentrations of approximately from 0.02% to 1% by volume with all combinations and subcombinations within the specified range.

Colloids in accordance with the present invention can be prepared using well-known technology specialists. For example, a colloidal dispersion system may be prepared using techniques such as, for example, the fragmentation of large particles, for example, in ball mills in the presence of the carrier liquid. Obtained by crushing the particles can be extracted from the media and then re-dispersed in the second carrier. Removing the particles can be carried out, for example, by means of flocculation (education flakes). The methods of preparation of colloids, including (ferro)magnetic fluids, which can be used for cooking Collot the two Papilla (Papell), U.S. patent No. 3917538 in the name of Rosenswig (Rosenswieg) and the book of Magnetic Fluids and Applications Handbook (guidance on the application of magnetic fluids), the authors of the Century Berkovsky, V. Bashtovoy, Publisher Begall Publishing House, NY, NY (1996) (USA).

EXAMPLES

Hereinafter in this description of the examples which are given for illustration only (explanations) of the present invention and are not of the nature to limit the invention.

Example 1

This example describes experiments that were conducted to evaluate the stability, dielectric strength and loss tangent at different concentrations of particles in transformer oil. The results of these experiments are summarized in the following table 1. Studied in these experiments the composition included the oil UNIVOLT60, which is a transformer mineral oil, which can be purchased at the company echop Corporation (St. Paul, MN, USA), as well as particles of iron oxide (Fe3About4as the magnetic particles and particles of TEFLONas non-magnetic particles, and oleic acid as surfactant. Used in this example, test methods meet the standards of ASTM. Voltage impul the data in table 1 data shows the colloids in the framework of the present invention (as shown, for example, in examples 1E and 1G-1M), which may have a concentration of the dispersed phase is approximately 2% by volume and the saturation magnetization (Ms) is approximately less than 50 Gauss, have a significantly higher dielectric strength compared to previously known colloidal liquids, which have a concentration of the dispersed phase is approximately more than 2% by volume and the saturation magnetization (Ms) of about 50 Gauss or more (see examples 1B-1D and 1F), and compared with pure oil (see example 1A). In particular, the colloids in the framework of the present invention have an increased positive values of impulse dielectric strength as compared with previously known colloids. These data indicate that colloids in the framework of the present invention have a greater tangent

the angle of dielectric losses at room temperature (25C) and at elevated temperature (100C).

Example 2

This example describes experiments that were conducted to evaluate and compare the cooling ability of colloidal fluids in accordance with the present invention with the cooling method is of 1, 5, 10, 30, 50, and 200 GS were prepared by dilution of the oil with colloid magnetite (FeOFe2About3). These colloidal liquids have been used as a coolant in the transformer 50 KVA, operating at a temperature of approximately 70C. as a control was used coolant, which contained only oil. Temperature sensors were installed in different places (top, middle, bottom (base)) around the windings of the transformer and the cooling fins. The data are summarized in the following table 2.

The analysis is shown in table 2 data shows that the colloids in the framework of the present invention, indicated, for example, in examples 2D, 2E, 2F and 2G, which have saturation magnetizations approximately less than 50 Gauss, provide improved cooling in different places around the transformer compared to the cooling provided by means of known fluids described in examples 2B and 2C, which have a saturation magnetization of about 50 Gauss or more, and compared to pure oil (example 2A). In particular, the temperature gradient between the top and in accordance with the present invention in comparison with the corresponding temperature gradient

when using previously known colloidal liquids. This means that colloidal fluid in accordance with the present invention provide improved circulation around the transformer.

The cooling of the transformer colloidal fluid in accordance with the present invention schematically shown in the drawing the drawing shows schematically the transformer 10, and the flow of the colloidal fluid around 12 of the transformer 10, in particular around the left windings 14 and right windings 16. Representative flow colloidal liquid 12 is the vector FAthat displays an upward arhimedova force acting on the heated colloidal liquid 12, and the vector FWiththat displays a downward component of Archimedean forces acting on the cooled part of the colloidal liquid 12. The vector FMis basically the same as for colloidal fluids in accordance with the present invention and for conventional previously known oils that can be used as an oil carrier in colloidal liquids in accordance with the present invention. The vector FAdisplays the force created by the magnetic interaction between the colloid is over the magnetic field across the width of the windings 16. In0represents the magnetic induction between the windings, and represents the magnetic flux inside the magnetic core. The specified magnetic field gradient causes the pressure drop across the width of the windings 16 and creates magnetohydrodynamic convection.

Example 3

Experiments were carried out to assess the impact of particle size on the electrical resistivity and dielectric strength colloidal coolant in accordance with the present invention. The results of these experiments are summarized in the following table 3.

The analysis is shown in table 3 data shows that the increase in the average particle size of approximately from less than 7 nm to more than 10 nm leads to approximately a tenfold increase in electric resistivity, as well as to a ten-fold reduction of power losses associated with the dielectric losses in the conductive components.

Despite what has been described the preferred embodiment of the invention, it is clear that it specialists in this field can be amended and supplemented, which do not extend, however, beyond Privedennaia liquid, containing approximately from to 99.5 to 99.99% by volume of the carrier liquid, and approximately from 0.01 to 0.5% by volume of non-metallic particles, and these particles are magnetic, and colloidal fluid has a saturation magnetization of approximately from 1 to 20 Gauss.

2. Colloidal fluid under item 1, characterized in that it contains approximately from 0.05 to 0.3% by volume of these particles.

3. Colloidal fluid under item 1, characterized in that it has an electric specific resistance, constituting approximately 109Omsee

4. Colloidal fluid under item 3, characterized in that it has an electric specific resistance, constituting approximately, at least, from 109to more than 1013Omsee

5. Colloidal fluid under item 1, characterized in that the carrier fluid is an oil.

6. Colloidal fluid under item 1, characterized in that the said particles selected from the group comprising inorganic particles, organic particles and carbon particles.

7. Colloidal fluid under item 6, characterized in that the said particles are inorganic particles.

8. Colloidal fluid under item 7, the Naya fluid under item 8, characterized in that the particles contain a metal oxide selected from the group comprising iron, zinc, manganese, titanium, copper, Nickel, chromium, and combinations thereof.

10. Colloidal fluid under item 6, characterized in that the said particles are carbon particles.

11. Colloidal fluid under item 1, characterized in that it further comprises a stabilizing material.

12. Colloidal fluid under item 11, characterized in that the stabilizing material contains a surfactant.

13. Colloidal fluid under item 1, characterized in that it has a saturation magnetization of approximately from 5 to 20 Gauss.

14. Colloidal fluid under item 1, characterized in that the particles have an average size from 1 to 100 nm.

15. Colloidal fluid under item 14, characterized in that the particles have an average size of approximately from 5 to 20 nm.

16. Colloidal fluid under item 15, characterized in that the particles have an average size of approximately from 7 to 20 nm.

17. Colloidal fluid under item 1, characterized in that it provides increased voltage impulse breakdown is approximately at least 10%.

18. The method of preparation study in the preparation of the carrier liquid and the introduction to the specified carrier fluid non-metallic particles from 0.01 to 0.5% by volume, moreover, these particles are magnetic.

19. The method according to p. 18, wherein said carrier fluid is an oil.

20. The method according to p. 18, characterized in that the said particles selected from the group comprising inorganic particles, organic particles and carbon particles.

21. The method according to p. 18, characterized in that the colloidal liquid has an electric specific resistance, constituting approximately more than 109Omsee

22. An electromagnetic device comprising means for creating an electromagnetic field and heat stable colloidal insulating fluid that is in contact with the specified tool and which contains a carrier fluid; and non-metallic particles, and these particles are magnetic, and colloidal insulating fluid has a saturation magnetization of from 1 to 20 Gauss.

23. The electromagnetic device according to p. 22, characterized in that it is a power transformer.

24. The method of isolation and cooling of the electromagnetic device, which produces an external magnetic field and heat, characterized in that it envisages the creation of a contact device which Itza, moreover, colloidal insulating fluid has a saturation magnetization in the range of approximately from 1 to 20 Gauss.

 

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Conductive filler // 2199556
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The invention relates to the field of electrical engineering, in particular to a technology for conductors with high conductivity

FIELD: electrical engineering; physical action-to-electric signal converters: strain-gage components, pressure sensors, push-button switches for handling electric signals.

SUBSTANCE: proposed electrically active polymer whose electrical activity depends on impact of external physical fields has molecular fragments possessing high polarizability and/or bistable electron energy structure with respect to excess electron capture process; molecular fragments are linked together through respective intermediate elements of molecular chain. Novelty is that electrically active molecular fragments form single macromolecular structure chemically bonded through molecular chains. Proposed material built around mentioned polymer is produced in the form of films or fibers, or coatings, or bodies of revolution; at least one of geometrical dimensions dictating material form does not exceed double depth of surface charge penetration.

EFFECT: enhanced response of material electric conductivity to external factors within wide film-thickness range; high reproducibility of useful properties.

81 cl, 1 tbl, 1 ex

FIELD: electrical engineering; proton conductors, their production, and electrochemical devices using them.

SUBSTANCE: proposed proton (H+)conductor has carbonic material essentially composed of carbon and proton dissociation groups introduced therein. Protons are moving in this proton conductor between proton dissociation groups. Ion conductance of proton conductor is higher than its electron conductance. Carbonic materials used for the purpose are carbon clusters, such as fullerene or carbonic tubular material, or so-called carbonic nanotubes having diamond-shaped structure. This conductor can be used in the form of thin film within wide temperature range at any humidity.

EFFECT: reduced size and simplified design of electrochemical device.

56 cl, 30 dwg, 3 tbl, 12 ex

FIELD: production of electric conducting pulp for manufacture of paper, reinforcing polymer materials and packaging films.

SUBSTANCE: pulp contains fibrous particles including 65-95 mass-% of para-amide and 5-35 mass-% of sulfonated polyaniline containing sulfur in the amount of 8.5-15 mass-% which is dispersed over entire para-amide partially covering the particles externally. Specific area of surface of fibrous particles exceeds 7.5 m2/g. Pulp may be mixed with 95 mass-% of pulp of other material including poly-n-phenylene terephthlamide. Paper made from this pulp reduces rate of electric charge lesser than 150 ml.

EFFECT: enhanced efficiency.

6 cl, 4 tbl, 1 ex

FIELD: power engineering, possible use for construction of supporting structures of sub-stations, distributing devices and other electric plants, meant for receiving, transforming and distributing electric energy of three-phase electric current of industrial frequency 50 Hz in networks with voltages range 35, 110, 150, 220 kV.

SUBSTANCE: modular electric plant consists of electric equipment, receiving assembly and bearing structure, formed of at least one module mounted on foundation , consisting of at least two rows of bearing posts of tubular shape, with at least two of them in each row with forming of flights in longitudinal and transverse directions; bearing beams, supported by bearing posts in each flight of longitudinal direction and mounted in pairs. Modules are constructed so, that bearing beams of separate modules are mutually parallel and/or mutually perpendicular, and electric equipment is mounted on foundation. Receiving assembly consists of at least one current-conducting wire, connected to at least one support, mounted on bearing structure of modular electric plant, while support consists of two polymer isolators, connected along height with forming of rigidity point, and current conducting wire is connected to support by holding assembly. The best variants of inventions from the group are realized with bolt connection of bearing structure elements and polymer isolators.

EFFECT: higher operational reliability of electric plant structures in case of upholding of unification and standardization principles due to development of modules, rational occupation of area occupied by distributing device, possible further expansion of operating electric plants, decreased metal capacity of bearing structure, decreased net costs of mounting operations and operation of electric plant, higher operational reliability of receiving assembly of modular electric plant due to support being capable of receiving static and dynamic loads, increased reliability of receiving assembly of modular electric plant due to development of modules.

2 cl, 4 dwg

FIELD: electric engineering industry.

SUBSTANCE: invention proposes a suspension for preparing current-conducting coat that comprises sodium meta-silicate, graphite, aluminum oxide, ferric (III) oxide, strontium carbonate, potassium titanate, barium oxide and hydrochloric acid taken in the following ratio of components, wt.-%: sodium meta-silicate, 28-30; graphite, 11-15.5; aluminum oxide, 3.5-3.7; ferric (III) oxide, 3.5-3.7; strontium carbonate, 3.5-3.7; potassium titanate, 4.2-4.5; barium oxide, 1.2-1.5; hydrochloric acid, 4.9-5.1, and water, the balance. Invention provides the creature of current-conducting coat with positive temperature resistance coefficient for conferring high resistance to heat loadings to it. Invention can be used in producing film heating surfaces and electric heaters.

EFFECT: valuable properties of suspension.

1 tbl

FIELD: electric engineering industry.

SUBSTANCE: invention proposes a suspension for preparing current-conducting coat that comprises sodium meta-silicate, graphite, aluminum oxide, ferric (III) oxide, strontium carbonate, potassium titanate, barium oxide and hydrochloric acid taken in the following ratio of components, wt.-%: sodium meta-silicate, 28-30; graphite, 11-15.5; aluminum oxide, 3.5-3.7; ferric (III) oxide, 3.5-3.7; strontium carbonate, 3.5-3.7; potassium titanate, 4.2-4.5; barium oxide, 1.2-1.5; hydrochloric acid, 4.9-5.1, and water, the balance. Invention provides the creature of current-conducting coat with positive temperature resistance coefficient for conferring high resistance to heat loadings to it. Invention can be used in producing film heating surfaces and electric heaters.

EFFECT: valuable properties of suspension.

1 tbl

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