Water and contamination absorber for C02 insulated electrical apparatus for the generation, transmission, distribution and/or usage of electrical energy

Abstract

The present invention relates to an electrical apparatus for generation, transmission, distribution and/or usage of electrical energy, comprising a housing enclosing an electrical apparatus interior space, at least a portion of which forms at least one insulation space having an electrical component and containing a surrounding insulation medium comprising an amount of carbon dioxide m.sub.co2. The insulation space is formed by at least one insulation space compartment, in which an adsorber for reducing or eliminating the amount of water m.sub.H2O and optionally further contaminants from the insulation medium is arranged. The amount of adsorber m.sub.ads arranged in the at least one insulation space compartment complies with the formulae (I) and (II). $\begin{array}{cc}{m}_{\mathrm{ads}}\frac{m_{H_{2}O}}{k_{\mathrm{ads},H_{2}O}}& \left(I\right)\\ m_{\mathrm{ads}}0.1\frac{m_{{\mathrm{CO}}_2}}{k_{\mathrm{ads},{\mathrm{CO}}_2}}& \left(\mathrm{II}\right)\end{array}$

Claims

1. Electrical apparatus for the generation, transmission, distribution and/or usage of electrical energy, said electrical apparatus comprising a housing enclosing an electrical apparatus interior space, at least a portion of the electrical apparatus interior space forming at least one insulation space, in which an electrical component is arranged and which contains an insulation medium surrounding the electrical component, the insulation medium comprising carbon dioxide, the insulation space comprising at least one insulation space compartment, in which an adsorber for reducing or eliminating an amount of water and further contaminants from the insulation medium is arranged, wherein an upper limit of an amount of the adsorber m.sub.ads complies with the following formula (II): $\begin{array}{cc}{m}_{\mathrm{ads}}0.1\frac{m_{{\mathrm{CO}}_2}}{k_{\mathrm{ads},{\mathrm{CO}}_2}}& \left(\mathrm{II}\right)\end{array}$ with m.sub.CO2 being the amount of carbon dioxide present in the respective insulation space compartment at the time when placing the adsorber into the insulation space compartment; and k.sub.ads,CO2 being the adsorption capability of the adsorber towards carbon dioxide at the predetermined temperature T.sub.0 at the time when placing the adsorber into the insulation space compartment, and wherein the insulation medium additionally comprises an organofluorine compound, and a lower limit of the amount of adsorber m.sub.ads arranged in the at least one insulation space compartment, in particular in each insulation space compartment, complies with the following formula (Ii): $\begin{array}{cc}{m}_{\mathrm{ads}}\frac{m_{H_{2}O}}{k_{\mathrm{ads},H_{2}O}}+\underset{i=1}{\overset{n}{.Math.}}\frac{m_{{\mathrm{dp}}_i}}{k_{\mathrm{ads},{\mathrm{dp}}_i}}& \left(\mathrm{Ii}\right)\end{array}$ with m.sub.H2O being the amount of water present in the respective insulation space compartment at the time when placing the adsorber into the insulation space compartment, k.sub.ads,H2O being the adsorption capability of the adsorber towards water at a predetermined temperature T.sub.0 at the time when placing the adsorber into the insulation space compartment, m.sub.dpi being the amount of a respective decomposition product dp.sub.1, dp.sub.2, . . . dp.sub.n created in and/or released into the respective insulation space compartment between gas maintenance or gas replacement intervals, with i being an index for the i-th decomposition product, and k.sub.ads,dpi being the adsorption capability of the adsorber towards the respective i-th decomposition product dp.sub.1, dp.sub.2, . . . dp.sub.n at the predetermined temperature T.sub.0, and at least one decomposition product is a decomposition product of the organofluorine compound.

2. Electrical apparatus according to claim 1, wherein the adsorber is a molecular sieve.

3. Electrical apparatus according to claim 2, wherein the molecular sieve is a zeolite.

4. Electrical apparatus according to claim 2, wherein the molecular sieve has an average pore size from 2 to 13 .

5. Electrical apparatus according to claim 1, wherein the insulation space is formed by at least two insulation space compartments separated from each other.

6. Electrical apparatus according to claim 5, wherein the volume of the at least two compartments differ from each other by a factor of at least 1.5.

7. Electrical apparatus according to claim 1, further comprising a desiccant selected from the group consisting of: calcium, calcium sulphate, in particular drierite, calcium carbonate, calcium hydride, calcium chloride, potassium carbonate, potassium hydroxide, copper(II) sulphate, calcium oxide, magnesium, magnesium oxide, magnesium sulphate, magnesium perchlorate, sodium, sodium sulphate, aluminium, lithium aluminium hydride, aluminium oxide, activated alumina, montmorrilonite, phosphorpentoxide, silica gel, a cellulose filter, and mixtures thereof.

8. Electrical apparatus according to claim 1, wherein the insulation medium further comprises a background gas selected from the group consisting of: air, air component, oxygen (O.sub.2), nitrogen (N.sub.2), nitrogen oxide, and mixtures thereof.

9. Electrical apparatus according to claim 8, wherein the insulation medium comprises the background gas consisting of a mixture of carbon dioxide and oxygen.

10. Electrical apparatus according to claim 9, wherein the ratio of the amount of carbon dioxide to the amount of oxygen ranges from 50:50 to 100:1.

11. Electrical apparatus according to claim 1, wherein the organofluorine compound is selected from the group consisting of: fluoroethers, in particular hydrofluoromonoethers, fluoroketones, in particular perfluoroketones, fluoroolefins, in particular hydrofluoroolefins, fluoronitriles, in particular perfluoronitriles, and mixtures thereof.

12. Electrical apparatus according to claim 1, wherein the insulation medium comprises a hydrofluoromonoether containing at least three carbon atoms.

13. Electrical apparatus according to claim 1, wherein the insulation medium comprises a fluoroketone containing from four to twelve carbon atoms.

14. Electrical apparatus according to claim 1, wherein the insulation medium comprises a perfluoroalkylnitrile, in particular a component selected from the group consisting of: perfluoroacetonitrile, perfluoropropionitrile (C.sub.2F.sub.5CN), perfluorobutyronitrile (C.sub.3F.sub.7CN), perfluoroisobutyronitrile (CF.sub.3).sub.2CFCN), perfluoro-2-methoxypropanenitrile (CF.sub.3CF(OCF.sub.3)CN), and mixtures thereof.

15. Electrical apparatus according to claim 1, wherein the amount of adsorber m.sub.ads arranged in each insulation space compartment complies with the formula (Ii): $\begin{array}{cc}{m}_{\mathrm{ads}}\frac{m_{H_{2}O}}{k_{\mathrm{ads},H_{2}O}}+\underset{i=1}{\overset{n}{.Math.}}\frac{m_{{\mathrm{dp}}_i}}{k_{\mathrm{ads},{\mathrm{dp}}_i}}.& \left(\mathrm{Ii}\right)\end{array}$

16. Electrical apparatus according to claim 1, wherein the electrical apparatus is a high voltage apparatus or a medium voltage apparatus.

17. Electrical apparatus according to claim 1, wherein the electrical apparatus is a part of or is a: high voltage apparatus, medium voltage apparatus, low voltage apparatus, direct-current apparatus, switchgear, air-insulated switchgear, part or component of air-insulated switchgear, gas-insulated metal-encapsulated switchgear (GIS), part or component of gas-insulated metal-encapsulated switchgear, air-insulated transmission line, gas-insulated transmission line (GIL), bus bar, bushing, air-insulated insulator, gas-insulated metal-encapsulated insulator, cable, gas-insulated cable, cable joint, current transformer, voltage transformer, sensors, surge arrester, capacitor, inductance, resistor, current limiter, high voltage switch, earthing switch, disconnector, load-break switch, circuit breaker, gas circuit breaker, vacuum circuit breaker, generator circuit breaker, medium voltage switch, ring main unit, recloser, sectionalizer, low voltage switch, transformer, distribution transformer, power transformer, tap changer, transformer bushing, electrical rotating machine, generator, motor, drive, semiconducting device, power semiconductor device, power converter, computing machine; and components and/or combinations of such devices.

18. Electrical apparatus according to claim 1, wherein the at least one insulation space compartment comprises a volume-specific amount of less than 5 kg adsorber per cubic meter.

19. Electrical apparatus for the generation, transmission, distribution and/or usage of electrical energy, the electrical apparatus comprising: a housing enclosing an electrical apparatus interior space, at least a portion of the electrical apparatus interior space forming at least one insulation space, in which an electrical component is arranged and which contains an insulation medium surrounding the electrical component, the insulation medium comprising carbon dioxide, the insulation space comprising at least one insulation space compartment, in which an adsorber for reducing or eliminating an amount of water and an amount of further contaminants from the insulation medium is arranged, wherein the at least one insulation space compartment comprises a volume-specific amount of less than 5 kg adsorber per cubic meter of the volume of the insulation space compartment, wherein the insulation medium additionally comprises an organofluorine compound, and a lower limit of the amount of adsorber m.sub.ads arranged in the at least one insulation space compartment complies with the following formula (Ii): $\begin{array}{cc}{m}_{\mathrm{ads}}\frac{m_{H_{2}O}}{k_{\mathrm{ads},H_{2}O}}+\underset{i=1}{\overset{n}{.Math.}}\frac{m_{{\mathrm{dp}}_i}}{k_{\mathrm{ads},{\mathrm{dp}}_i}}& \left(\mathrm{Ii}\right)\end{array}$ with m.sub.H2O being the amount of water present in the respective insulation space compartment at the time when placing the adsorber into the insulation space compartment, k.sub.ads,H2O being the adsorption capability of the adsorber towards water at a predetermined temperature T.sub.0 at the time when placing the adsorber into the insulation space compartment, m.sub.dpi being the amount of a respective decomposition product dp.sub.1, dp.sub.2, . . . dp.sub.n created in and/or released into the respective insulation space compartment between gas maintenance or gas replacement intervals, with i being an index for the i-th decomposition product, and k.sub.ads,dpi being the adsorption capability of the adsorber towards the respective i-th decomposition product dp.sub.1, dp.sub.2, . . . dp.sub.n at the predetermined temperature T.sub.0, and at least one decomposition product is a decomposition product of the organofluorine compound.

20. Electric apparatus according to claim 19, wherein the at least one insulation space compartment comprises a volume-specific amount of less than 1.25 kg adsorber per cubic meter.

21. Electric apparatus according to claim 19, wherein the electrical component is a non-circuit-breaker component and the at least one insulation space compartment comprises a volume-specific amount of less than 2 kg adsorber per cubic meter.

22. Electrical apparatus according to claim 19, wherein the predetermined temperature is room temperature.

23. Electrical apparatus according to claim 1, wherein the amount of adsorber m.sub.ads is such that when introducing the adsorber into the insulation space compartment, the insulation medium undergoes a change in the partial pressure of CO.sub.2 of less than 15%.

24. Electrical apparatus according to claim 1, wherein the amount of adsorber m.sub.ads is selected closer to the upper limit given by formula (II) than to the lower limit given by formula (Ii).

25. Electrical apparatus according to claim 1, wherein the amount of adsorber m.sub.ads is selected such that the lower limit given by formula (Ii) is determined at a first predetermined temperature T.sub.1, the upper limit given by formula (II) is determined at a second predetermined temperature T.sub.2, and the first predetermined temperature T.sub.1 is chosen higher than the second predetermined temperature T.sub.2.

26. Electrical apparatus according to claim 24, wherein the amount of adsorber m.sub.ads is selected such the first predetermined temperature T.sub.1 is chosen equal to or higher than the predetermined temperature T.sub.0 and in particular about room temperature, and the second predetermined temperature T.sub.2 is chosen smaller than the predetermined temperature T.sub.0 and in particular lower than room temperature or equal to the minimal operating temperature of the electrical apparatus.

27. Method for determining an optimum amount of an adsorber for the adsorption of water and further contaminants in an electrical apparatus for the generation, transmission, distribution and/or usage of electrical energy, the electrical apparatus comprising a housing enclosing an electrical apparatus interior space, at least a portion of the electrical apparatus interior space forming at least one insulation space, in which an electrical component is arranged and which contains an insulation medium surrounding the electrical component, the insulation medium comprising carbon dioxide, the insulation space comprising at least one insulation space compartment, the method comprising: a) determining for the at least one insulation space compartment the amount of water m.sub.H2O present in the insulation space compartment at the time when placing the adsorber into the insulation space compartment; b) determining for the at least one insulation space compartment the amount of carbon dioxide m.sub.CO2 present in the insulation space compartment at the time when placing the adsorber into the insulation space compartment; wherein the insulation medium additionally comprises an organofluorine compound, c) determining for the at least one insulation space compartment the lower limit of the amount of adsorber m.sub.ads by formula (Ii): $\begin{array}{cc}{m}_{\mathrm{ads}}\frac{m_{H_{2}O}}{k_{\mathrm{ads},H_{2}O}}+\underset{i=1}{\overset{n}{.Math.}}\frac{m_{{\mathrm{dp}}_i}}{k_{\mathrm{ads},{\mathrm{dp}}_i}}& \left(\mathrm{Ii}\right)\end{array}$ with k.sub.ads,H2O being the adsorption capability of the adsorber towards water at a predetermined temperature T.sub.0 or at a first predetermined temperature T.sub.1 at the time when placing the adsorber into the insulation space compartment, m.sub.dpi being the amount of a respective decomposition product dp.sub.1, dp.sub.2, . . . dp.sub.n created in and/or released into the respective insulation space compartment between gas maintenance or gas replacement intervals, with i being an index for the i-th decomposition product, and k.sub.ads,dpi being the adsorption capability of the adsorber towards the respective i-th decomposition product dp.sub.1, dp.sub.2, . . . dp.sub.n at the predetermined temperature T.sub.0 or at the first predetermined temperature T.sub.1, with at least one decomposition product being a decomposition product of the organofluorine compound, and d) determining for the at least one insulation space compartment the upper limit of the amount of adsorber m.sub.ads by formula (II) $\begin{array}{cc}{m}_{\mathrm{ads}}0.1\frac{m_{{\mathrm{CO}}_2}}{k_{\mathrm{ads},{\mathrm{CO}}_2}}& \left(\mathrm{II}\right)\end{array}$ with k.sub.ads,CO2 being the adsorption capability of the adsorber towards carbon dioxide at the predetermined temperature T.sub.0 or at a second predetermined temperature T.sub.2 at the time when placing the adsorber into the insulation space compartment.

28. Method according to claim 27, including the method element of selecting the amount of adsorber m.sub.ads closer to the upper limit given by formula (II) than to the lower limit given by formula (II).

29. Method according to claim 27, including the method element of selecting the amount of adsorber m.sub.ads such that the lower limit given by formula (Ii) is determined at the first predetermined temperature T.sub.1, the upper limit given by formula (II) is determined at the second predetermined temperature T.sub.2, and the first predetermined temperature T.sub.1 is chosen higher than the second predetermined temperature T.sub.2.

30. Method according to claim 29, wherein the amount of adsorber m.sub.ads is selected such the first predetermined temperature T.sub.1 is chosen equal to about room temperature, and the second predetermined temperature T.sub.2 is chosen lower than room temperature or equal to the minimal operating temperature of the electrical apparatus.

31. Method according to claim 27, wherein the amount of adsorber is such that when introducing the adsorber into the insulation space compartment, the insulation medium undergoes a change in the partial pressure of CO.sub.2 of less than 15%.

32. Method according to claim 27, wherein the predetermined temperature is selected equal to room temperature.

Description

EXAMPLE

(1) For a zeolite having an average pore size of about 5 , the optimum amount for its use in an electrical apparatus comprising passive components was determined as follows:

(2) For determining the lower limit of the amount of zeolite, the amount of water in the insulation space compartment was calculated by multiplying the amount of polymeric material contained in the insulation space compartment with the amount of water contained in the polymeric material, adding 1 g of water per square meter directly exposed to the insulation medium and further adding 1 g of water relating to an empirical value for the diffusion of water through sealings over long term operation of the apparatus of up to 30 years. Since 10 kg of polymeric material containing 2 g of water per kg is contained in the insulation space compartment (approximately at the order of a cubic meter), the total amount of water to be adsorbed is 22 g.

(3) For a k.sub.ads,H2O of the adsorber of about 0.147, the lower limit of the amount of adsorber defined by

(4) 0$m_{\mathrm{ads}}\frac{m_{H_{2}O}}{k_{\mathrm{ads},H_{2}O}}$
is thus 110 g.

(5) The upper limit was determined according to the formula

(6) $m_{\mathrm{ads}}0.1\frac{m_{{\mathrm{CO}}_2}}{k_{\mathrm{ads},{\mathrm{CO}}_2}}$

(7) Given an amount m.sub.CO2 of CO.sub.2 of about 8.8 kg (about 5 bar) and given a k.sub.ads,CO2 of the zeolite of about 0.2, the upper limit of zeolite is 4.4 kg. The optimum amount of zeolite to be introduced in the insulation space compartment is thus between 110 g and 4.4 kg.

(8) Throughout this application, terms like preferable particular, particularly preferred, etc. designate optional embodiments only.