Electrical device having a plurality of cooling units

Abstract

An electrical device connects to a high-voltage network and has a vessel, which is filled with an insulating fluid, an active part, which is arranged in the vessel and which has a magnetizable core and partial windings for producing a magnetic field in the core, and a cooling apparatus for cooling the insulating fluid. The electrical device is economical and at the same time can be operated at higher temperatures. This is achieved by use of at least one thermal barrier, which delimits cooling spaces, in each of which at least one partial winding is arranged. The cooling apparatus has at least two cooling units and each cooling unit being configured to cool an associated partial winding.

Claims

1. An electrical device for connecting to a high-voltage network, the electrical device comprising: a vessel filled with an insulating fluid; an active part disposed in said vessel and having a magnetizable core and partial windings for generating a magnetic field in said magnetizable core, at least one of said partial windings having temperature regions in which insulating materials of different thermal loadability are disposed; at least one thermal barrier delimiting cooling spaces and in each of said cooling spaces is disposed at least one of said partial windings; and a cooling device for cooling said insulating fluid, said cooling device having at least two cooling units, and each of said cooling units is configured to cool an associated one of said partial windings, said cooling device further having a control unit with temperature sensors, said temperature sensors configured to detect a temperature of a partial winding of said partial windings and/or to detect a temperature of said insulating fluid in said partial winding, wherein in each case one of said temperature sensors for measuring a hotspot temperature is disposed in at least two of said temperature regions and provides temperature measurement values on an outlet side which are compared with a threshold value predetermined in dependence on said insulating materials used in a respective one of said temperature regions, wherein a control signal is generated on a basis of a comparison.

2. The electrical device according to claim 1, wherein: said cooling device has an outlet; and said thermal barrier forms at least one inlet opening which is connected to said outlet of said cooling device.

3. The electrical device according to claim 1, wherein said thermal barrier encloses said partial winding at least in certain portions.

4. The electrical device according to claim 1, wherein said thermal barrier is an electrical barrier at least in certain portions.

5. The electrical device according to claim 1, wherein said partial windings include a first partial winding being a low-voltage winding, and a second partial winding being a high-voltage winding, wherein said first and second partial windings are disposed concentrically to one another and to said magnetizable core which extends through said low-voltage winding being an inner low-voltage winding.

6. The electrical device according to claim 5, wherein said two cooling units include a first cooling unit configured to cool said low-voltage winding and a second cooling unit configured to cool said high-voltage winding.

7. The electrical device according to claim 6, further comprising an expansion vessel, a cooling space in which said high-voltage winding is disposed is hydraulically coupled to a cooling space in which said low-voltage winding is disposed via said expansion vessel.

8. The electrical device according to claim 6, wherein at least one of said first and second cooling units is connected to a winding base and/or a winding top of one of said partial windings in such a way that flows of said insulating fluid that are in each case guided via said first and second cooling units during normal operation are separated from one another.

9. The electrical device according to claim 6, wherein each of said first and second cooling units has a cooling register.

10. The electrical device according to claim 9, wherein said cooling registers have different vertical spacings from a bottom plane defined by a bottom surface of said vessel.

11. The electrical device according to claim 1, wherein said partial windings have different partial winding insulations.

12. An electrical device for connecting to a high-voltage network, the electrical device comprising: a vessel filled with an insulating fluid; an active part disposed in said vessel and having a magnetizable core and partial windings for generating a magnetic field in said magnetizable core, at least one of said partial windings having temperature regions in which insulating materials of different thermal loadability are disposed; at least one thermal barrier delimiting cooling spaces and in each of said cooling spaces is disposed at least one of said partial windings; a cooling device for cooling said insulating fluid, said cooling device having at least two cooling units, and each of said cooling units is configured to cool an associated one of said partial windings, said cooling device further having a control unit with temperature sensors, said temperature sensors configured to detect a temperature of a partial winding of said partial windings and/or to detect a temperature of said insulating fluid in said partial winding, wherein a plurality of fluidically connected said temperature regions in a cooling space are equipped with said temperature sensors for measuring a hotspot temperature of said partial winding in a respective temperature region, and signals of each of said temperature sensors are each assigned dedicated threshold values for triggering control functions which are tailored to a thermal class of said insulating materials used in said respective temperature regions of said partial winding.

13. An electrical device for connecting to a high-voltage network, the electrical device comprising: a vessel filled with an insulating fluid; an active part disposed in said vessel and having a magnetizable core and partial windings for generating a magnetic field in said magnetizable core, said partial windings including a first partial winding being a low-voltage winding, and a second partial winding being a high-voltage winding, said first and second partial windings disposed concentrically to one another and to said magnetizable core extending through said low-voltage winding being an inner low-voltage winding; at least one thermal barrier delimiting cooling spaces and in each of said cooling spaces is disposed at least one of said partial windings; and a cooling device for cooling said insulating fluid, said cooling device having at least two cooling units, and each of said cooling units is configured to cool an associated one of said partial windings, said two cooling units including a first cooling unit configured to cool said low-voltage winding and a second cooling unit configured to cool said high-voltage winding; a controller; sensors and dedicated sensors; and said partial windings are fluidically and thermally separated partial windings and have said dedicated sensors for temperature monitoring of a winding temperature and/or said sensors for measuring a maximum insulating fluid temperature in thermally separated said cooling spaces of said partial windings, and said sensors are connected to said control unit which is provided with means for monitoring an observance of admissible temperatures of said partial windings and/or of said insulating fluid, which are different for each cooling space, and for independently controlling said cooling units respectively assigned to a cooling space.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) Further expedient embodiments and advantages of the invention form the subject matter of the following description of exemplary embodiments of the invention with reference to the figures of the drawing, in which identical reference signs refer to identically acting components and in which

(2) FIGS. 1 to 7 schematically illustrate different exemplary embodiments of the electrical device according to the invention in a partially sectioned side view.

DESCRIPTION OF THE INVENTION

(3) FIG. 1 shows a first exemplary embodiment of the electrical device 1 according to the invention in a sectioned side view, wherein the electrical device is configured as a transformer 1. The transformer 1 has a vessel 14 in which a magnetizable core 2, a low-voltage winding 3.1 and a high-voltage winding 3.2, each as partial winding within the sense of the invention, are arranged concentrically to one another. Said windings 3.1, 3.2 are of hollow-cylindrical design. The high-voltage winding 3.2 can be connected to a high-voltage network via a connection (not shown in the figure), while the low-voltage network 3.1 can be connected to a distribution network or a load via a connection line (not shown either). The high-voltage and low-voltage winding 3.1, 3.2 are inductively coupled to one another via the magnetizable core 2, with the result that the high-voltage winding 3.2 induces a voltage in the low-voltage winding 3.1, or vice versa.

(4) The vessel 14 is filled with an insulating fluid 30 and, in the present case, with a commercially available ester. A thermal barrier 4 is arranged between the high-voltage winding 3.2 and the low-voltage winding 3.1. The thermal barrier 4 is circumferentially closed and likewise of hollow-cylindrical design. Here, it completely encloses the likewise cylindrical low-voltage winding 3.1. Above the vessel 14 there is arranged an expansion vessel 18 which serves to take up the temperature-induced volume fluctuations of the insulating fluid 30.

(5) In order to cool the partial windings 3.1 and 3.2, a cooling device is provided which has two cooling units, wherein a first cooling unit has a cooling register 15.1, a circulating pump 16.1 and a temperature sensor 22.1, a supply line 37.1 and a return line 38.1. The second cooling unit has a cooling register 15.2, a circulating pump 16.2, a temperature sensor 22.2, a supply line 37.2 and a return line 38.2. The supply line 37.1 has an outlet opening 32 which is arranged below the radially inner low-voltage winding 3.1. An inlet opening of the return line 38.1 is directly connected to a winding top 9.1 of the winding 3.1. The winding top 9.1 is fluidically sealed, by which is meant that the flow of the insulating fluid 30 is guided by the winding top. The return line 38.1 is connected via a connection line to the expansion vessel 18, which in turn is connected via a second connection line to the interior of the vessel 14 of the transformer 1. The supply line 37.2 of the second cooling unit opens by way of its outlet opening directly in the side wall of the vessel 14. The return line 38.2 is connected close to the upper edge of the vessel. The inner wall of the thermal barrier 4 thus delimits a first cooling space in which the low-voltage winding 3.1 is arranged. The outer wall of the thermal barrier 4 delimits, together with the vessel 14, a second cooling space in which the high-voltage winding 3.2 is situated. According to the exemplary embodiment illustrated in FIG. 1, the insulating fluid 30 cooled by the first cooling unit 15.1, 16.1, 37.1, 38.1 is guided via the sealed winding base 8.1 directly to the low-voltage winding 3.1 and from there directly back to the cooling register 15.1. In this exemplary embodiment, the hydraulic coupling of the cooling spaces occurs only via the expansion vessel 18. Different cooling space temperatures are established in the cooling spaces. The insulations are each adapted to these cooling space temperatures.

(6) The temperature sensors 22.1 and 22.2 are each connected to a control unit (not shown in the figure) via a signal line. If the temperature of the insulating fluid 30 that is detected by the temperature sensors 22.1 or 22.2 exceeds a threshold value predetermined for the respective partial winding 3.1 or 3.2, the control unit increases the power of the circulating pump and thus the power of the respective cooling unit. The threshold values have been determined in dependence on the thermal class of the insulating materials of the respective partial windings.

(7) FIG. 2 shows an exemplary embodiment of the electrical device 1 according to the invention, in which the hydraulic coupling of the cooling circuits occurs via the upwardly open winding tops 9.1, 9.2 of the partial windings 3.1, 3.2. Mixing of the insulating fluid 30 occurs above the partial windings 3.1 and 3.2. The insulating fluid 30 is differently cooled in the cooling units each assigned to a partial winding 3.1, 3.2. Thus, a higher cooling effort is implemented in the cooling circuit for the partial winding 3.2 whose winding conductors are equipped with an elaborate high-voltage insulation. In other words, the insulating fluid 30 is cooled to a lower temperature.

(8) The cooling space of the partial winding 3.1 and the core 2 are incorporated in the cooling circuit formed via the cooler 15.2.

(9) The partial winding 3.1 with lower requirements on its withstand voltage, which thus has a small number of insulating materials by comparison with the other partial winding, is equipped with an insulation of a higher thermal class and can thus be operated at higher temperature. Equipping this partial winding with high-temperature insulating materials requires only low costs. Within the scope of the invention, it is expedient to operate partial windings with a comparatively low withstand voltage at a higher temperature than the partial windings with a high withstand voltage.

(10) Designing the core 2 for higher temperatures requires only a very small effort since no moldings are required and an electrical field loading does not have to be taken into consideration. Accordingly, the core 2 is likewise exposed to higher operating temperatures.

(11) The supply of the insulating fluid 30, which is cooled in separate cooling units, to the partial windings 3.1 and 3.2 occurs via the winding base 8.1, 8.2 of the respective partial winding 3.1 or 3.2.

(12) The winding base 8.1, 8.2, each built up in layers, is used for the separate supply of the insulating fluid 30 to the partial windings 3.1, 3.2 separated by the thermal barrier. The insulating material disks (not illustrated in detail here) of the respective winding base 8.1, 8.2 are designed in such a way that a separation of the flow of the insulating fluid 30 to the respective partial windings 3.1, 3.2 is provided.

(13) In order to decouple the fluid flows, the winding bases 8.1 and 8.2 are sealed with respect to one another. Furthermore, at least one connection line 37.1 is provided which extends between the cooling unit 15.1, 16.1 and the winding base 8.2, with the result that the flow of the cooled insulating fluid is sealed with respect to the interior of the vessel 14. In the exemplary embodiment, the cooling register 15.1 is directly connected to the winding base 8.2 via a pipeline 37.1.

(14) In the exemplary embodiment, the spaces 40 between the partial windings 3.2 and the vessel 14 that are not required for cooling or for guiding the insulating fluid 30 are closed by means of shims 11.2 in order to avoid bypasses.

(15) FIG. 3 shows a further exemplary embodiment of the invention having two cooling spaces separated by the thermal barrier 4. The thermal barrier 4 comprises cylindrical portions 4.1 and 4.2 and a separating wall 4.5. In the exemplary embodiment shown, the thermal barrier 4 produced from a thermally insulating material brings about thermal and fluidic decoupling of the radially outer partial winding 3.2 from the inner partial winding 3.1 and the core 2 of the transformer 1. In other words, the decoupling is achieved by the separation of the insulating fluid flows of the two cooling circuits by means of the thermal barrier 4.

(16) In the exemplary embodiment shown, an electrical barrier 7 is integrated as a portion into the barrier 4. For thermal separation of the insulating fluid flow, the winding base 8.2 of the partial winding 3.2 is fluidically connected to the supply line 37.2, which leads to the cooler register 15.2 of the second cooling unit that is arranged outside of the vessel. The radially inner partial winding 3.1 and the cooling ducts of the core 2 are open toward the fluid space of the vessel 14. Furthermore, the supply line 37.1 of the first cooling register 15.1 is connected to the vessel 14 at a height below the lower edge of the partial winding 3.1. The inner partial winding 3.1 and the core 2 are thus supplied with cooled insulating fluid 30 by “free”, that is to say nonguided, flow. In addition to a winding base 8.1 or 8.2, each partial winding has a winding top 9.1, 9.2. Each winding top 9.1 and 9.2 is open toward the fluid space of the vessel 14. Through the openings of their winding top 9.1, 9.2, in the exemplary embodiment the two cooling spaces are hydraulically connected to one another via the vessel interior, that is to say the fluid space of the vessel 14.

(17) In order to take up the thermally induced volume fluctuations of the insulating fluid 30, the interior of the vessel 14, and thus the two cooling spaces, are connected to the expansion vessel 18. Thermal stratification of the insulating fluid 30 occurs within said fluid spaces of the transformer 1 as a result of the temperature dependency of the density of the insulating fluid 30. This thermal stratification is increased by a high viscosity of the insulating fluid 30 used and the very low flow velocities in the large cross section. In the specific exemplary embodiment, this effect is used for thermal separation of the two cooling circuits. For this purpose, according to the invention, the connection of the return line 38.2 to the cooling register 15.2 is arranged below the connection of the return line 38.1 to the cooling register 15.1. In order to avoid mixing of the insulating fluid 30 heated to different degrees, a further portion 4.5 of the thermal barrier 4 is provided in the usually open region above the windings. This portion 4.5 projects above the electrical barrier 7. In the exemplary embodiment, the vertical spacing H5 from the upper edge of the portion 4.5 of the thermal barrier 4 to the return line 38.2 is a multiple of the flow-delimiting diameter of the return line 38.2. This prevents a situation in which considerably more highly heated insulating fluid 30 which has flowed through the low-voltage winding 3.1 passes into the return line 38.2.

(18) In order to avoid the formation of bypasses, potential undesired flow ducts 10.5, for example between portions 7.5 of the barrier system 4 and the electrical barrier 7, are completely or partially closed at one of their ends by means of shims consisting of insulating material.

(19) In the exemplary embodiment shown, the partial windings 3.1 and 3.2 within the cooling spaces form temperature regions 5.1, 5.2, 5.3 or 6.1, 6.2 which are situated vertically above one another and which are equipped with an electrical insulation consisting of insulating materials which have a thermal loadability which differs from temperature region to temperature region. Thus, the thermal loadability of the insulating materials in the temperature region 5.1 through which insulating fluid 30 first flows is less than the insulating materials of the temperature regions arranged downstream in the flow direction. Moreover, it is also possible to use insulating materials of different thermal classes, at least partially, within the temperature regions. Thus, the thermal loadability of an insulating material can be less if it maintains the necessary spacing from the hottest point of the temperature region, that is to say, for example, from a certain winding layer. It is thus possible, for example, for a gradation of the thermal class to occur within a temperature region 5.1 depending on whether the insulating material is used as conductor insulation, spacer, potential control ring or barrier.

(20) This arrangement can be applied for a wide variety of insulating materials and hence different temperature regions. An exemplary assignment of the thermal classes to the temperature regions illustrated in the exemplary embodiment is indicated below. In the exemplary embodiment, use is made of an insulating fluid based on an ester.

(21) Design example for a winding arrangement according to FIG. 3 (thermal classes of the insulating materials in accordance with EN 60085:2008)

(22) TABLE-US-00001 Temperature region 5.1 5.2 5.3 6.1 6.2 Conductor B (130° C.) F (155° C.) H (180° C.) E (120° C.) B (130° C.) insulation Spacer E (120° C.) B (130° C.) F (155° C.) A (105° C.) E (120° C.) Barrier A (105° C.) E (120° C.) B (130° C.) A (105° C.) A (105° C.) system/potential control rings

(23) In this connection, the term “spacer” is intended to encompass radial and axial spacers, such as, for example, bars, riders, interlayers or the like. The term “barrier system” is intended to include barriers, angle rings, caps, disks, insulating cylinders or the like.

(24) The gradation of the thermal efficiency of the insulating materials can also be undertaken within the thermal classes in accordance with EN 60085, a large number of possibilities existing here, with, for example, a gradation in increments of less than 10 K also being possible.

(25) Furthermore, in the exemplary embodiment, the hotspots of the temperature regions are equipped with thermal sensors 25.1, 25.2, 25.3, 26.1 and 26.2 which are each connected to a control unit (not shown in the figure). In the exemplary embodiment, furthermore, a sensor 27, 28 for measuring the maximum temperature of the insulating liquid 30 is arranged in the region of the respective outlet opening in the winding top 9.1 or 9.2.

(26) In FIG. 3, five temperature regions 5.1, 5.2, 5.3, 6.1, 6.2 are thus provided which are each equipped with insulating materials from 3 different thermal classes. Thus, different admissible maximum temperatures are obtained for each temperature region. The insulating liquid 30 must not achieve the admissible maximum temperature for the insulating fluid in the temperature regions arranged ahead in the flow progression, since otherwise the temperature gradient from the winding to the insulating fluid 30 in the winding regions through which flow subsequently passes becomes too low for sufficient cooling.

(27) Since, as described, the admissible temperatures are different in the different temperature regions, it makes sense for the temperatures in the temperature regions to be monitored separately. In the exemplary embodiment, the hotspots of all temperature regions are therefore equipped with thermal sensors, and the signals are sent to a control unit. Each of these signals is assigned a threshold value which is tailored to the thermal class of the insulating materials of the corresponding winding region. If one of the temperature signals exceeds the threshold value assigned thereto, a control signal is generated. Depending on the design, it can trigger a warning signal, bring about shutdown, trigger a reduction in the load of the electrical device or else be used to control the cooling system.

(28) The signal of each temperature sensor 25.1, 25.2, 25.3, 26.1, 26.2 is preferably assigned different threshold values for cooling system control, warning and triggering.

(29) FIG. 4 shows a further exemplary embodiment in which a cooling unit is configured as an active cooling unit and has a circulating pump 16.2, whereas the other cooling unit is a passive cooling unit 15.1 in which the insulating fluid 30 is circulated via the cooling register 15.1 on the basis of a temperature difference which arises.

(30) In the exemplary embodiment shown, the winding 3.2 having the higher high-voltage requirements, that is to say the winding with a high proportion of insulating materials and insulating parts which are to be manufactured in an elaborate manner, is cooled in a forced manner by the active cooling unit 15.2, 16.2. The partial winding 3.2 is again enclosed by cylindrical portions 4.1 of the thermal barrier 4. The cooled insulating fluid 30 is supplied via the fluidically sealed winding base 8.2, which is connected to the cooling unit 15.2 and the pump 16.2 via the supply line 37.2.

(31) The vessel 14 is also connected to the cooling register 15.1. The more strongly cooled partial winding 3.2 is provided with insulating materials of a low thermal class. Since, during operation of a transformer 1 shown, large differences in the temperatures of the insulating fluid 30 are established inside and outside of the thermal barrier 4, additional barrier portions 4.6 are provided which avoid a fluid flow directly on the wall of the barrier 4.2 and thus reduce the thermal influencing of the partial winding 3.2. In the exemplary embodiment, for this purpose, there are provided, directly following the barrier portion 4.2, electrical barriers and angle rings with shims which prevent the fluid flow within the duct between the barriers.

(32) In this exemplary embodiment, only the partial winding 3.1 has two temperature regions 5.1 and 5.2. With regard to the temperature regions, the statements pertaining to FIG. 6 correspondingly apply here.

(33) FIG. 5 illustrates an exemplary embodiment of a transformer 1 having natural cooling (ONAN cooling). Here, the movement of the insulating liquid is caused by thermal buoyancy. The insulating fluid 30 heated by the partial windings 3.1, 3.2 rises on account of its lower density with respect to the insulating liquid 30 of the further surroundings of the winding and is replaced by cold insulating liquid 30 flowing in from below. The weight difference between the hot liquid column in the winding ducts and the cooler liquid column in the cooling register 15.1 or 15.2 produces a pressure difference which serves as driving force for the fluid circuit. Moreover, a higher geometric arrangement of the cold insulating fluid column of the cooling register leads to an increase in the pressure difference that drives the cooling medium flow. This effect is used in the exemplary embodiment to supply a winding 3.1 with an increased pressure and thus a higher volumetric flow of the insulating liquid. For this purpose, the cooling register 15.1 which supplies the winding 3.1 with cooled insulating fluid is arranged at a greater spacing from the center of the winding 3.1 than the cooling register 15.2 which is provided to supply the partial winding 3.2 and the core 2.

(34) On account of the fixed spacing of the partial winding from a bottom plane defined by the bottom of the vessel, this height offset is here described by the spacing of the respective cooling register from said bottom plane. These different height positions are therefore considered here as a vertical spacing H1, H2 of the respective cooling register 15.1, 15.2 from the bottom plane which is defined by the bottom of the vessel 14.

(35) H1 is greater than H2. Since the two partial windings 3.1 and 3.2 are supported on the lower yoke of the core 4, the centers thereof are situated approximately at the same height. Accordingly, the spacing between the center of the first cooler 15.1 and the center of the first winding 3.1 is greater than the spacing between the center of the second cooler 15.2 and the center of the second winding 3.2.

(36) If this driving force becomes too high, a strong secondary flow of the insulating fluid 30 between partial winding and vessel wall of the transformer 1 then occurs on account of the flow resistance in the winding, said flow reducing the effectiveness of the cooling. In order to avoid this, in the exemplary embodiment the cooled insulating fluid 30 is supplied to the winding 3.1, which is connected to the cooling unit 15.1 arranged higher, via the winding base 8.1 which is fluidically sealed for this purpose.

(37) The insulating fluid flow is thus adapted to the different operating temperatures of the two partial windings and their different flow resistances.

(38) Within the scope of the invention, the cooling registers 15.1 and/or 15.2 can be equipped with fans.

(39) FIG. 6 shows a further exemplary embodiment of the electrical device 1 according to the invention, which differs from the exemplary embodiment shown in FIG. 5 to the effect that the cooling registers 15.1 and 15.2 are equipped with fans or blowers 17. Here, the cooling register 15.1 and the cooling register 15.2 have a different number of fans 17. Moreover, the cooling registers 15.1 and 15.2 are situated at the same height. The supply line 37.1 of the first cooling unit is arranged exactly below the first partial winding 3.1, that is to say the low-voltage winding. By contrast with the exemplary embodiments shown in FIGS. 1 to 5, the thermal barrier 4 extends as far as the upper wall of the vessel 14, the return line 38.1 connecting the cooling space within the thermal barrier 4 to the cooling register 15.1. The first cooling unit therefore again forms a closed circulating cooling circuit, wherein the hydraulic coupling between the first cooling space and the second cooling space, which is defined by the outer wall of the thermal barrier 4 and the inner wall of the vessel 14, is achieved via the expansion vessel 18. For this purpose, the corresponding connection lines are provided.

(40) Since, in the exemplary embodiment, the thermal and fluidic separation of the windings also continues above the windings, the two cooling spaces are each equipped with a dedicated Buchholz relay 20 in order to monitor gas accumulations in the two cooling spaces.

(41) With increasing loading of the transformer 1, the temperatures in the two partial windings 3.1, 3.2 increase differently and are first cooled without fan assistance (ONAN cooling). The fans 17 are activated or controlled differently at different temperatures for the two partial systems for each cooling circuit.

(42) In the exemplary embodiment, the cooling unit for the cooling space with the partial winding which is equipped with insulating materials of a lower thermal class is already switched to fan operation at a lower temperature than the cooler for the partial winding with insulating materials of a higher thermal class. In order to be able to operate the two partial windings at full load, the cooling register 15.2 has a larger number of fans 17 than the cooling register 15.2.

(43) FIG. 7 shows a further exemplary embodiment of the invention of the electrical device 1 according to the invention, which substantially corresponds to the exemplary embodiment according to FIG. 1, although the cooling units 15.1 and 15.2 are each designed as passive cooling units, with the result that neither of the cooling units has a circulating pump.

(44) Further components (not shown here) of the electrical device 1, for example tap changers, are assigned, corresponding to their respectively admissible operating temperature, to one of the two cooling spaces.