JPH118129A - Oil-filled dc equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit a temperature rise of a coil end part insulating means to prevent the severity degree of the DC withstand voltage of the insulating means from rising, by a method wherein an oil-filled DC equipment is provided with a means for preventing insulating oil subjected to temperature rise by cooling a coil from flowing in the insulating means. SOLUTION: Insulating oil subjected to temperature rise by cooling a coil 1 is dammed by damming cocks 28a and 28b, and an insulating barrier 28c is prevented from flowing in a coil end part insulating means 101, while, after cooled insulating oil is flowed in a coil end part insulating means 102 through an oil guide box 7, it is branched in an inner peripheral space of an inner peripheral insulating cylinder 3 through an oil guide hole 26b formed in the cylinder 3 as shown by corrugated lines, and is flowed in the means 101 through an oil guide hole 26a. As a result, the means 101 is never subjected to temperature rise regardless of the generation of heat of the coil 1. Accordingly, the extent of the DC withstand voltage of the means 101 and the extent of insulation of the means 102 under the lower part of the coil can be lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil-filled DC device such as an oil-filled transformer or an oil-filled DC reactor used for DC power transmission and the like.

[0002]

2. Description of the Related Art FIG.
FIG. 1 is a cross-sectional view illustrating a main part of a conventional DC reactor device disclosed in Japanese Patent Laid-Open Publication No. H10-15095. In the drawing, reference numeral 1 denotes a coil formed by stacking a plurality of disc-shaped single coils at intervals, and 2 denotes a coil disposed at an axial end of the coil 1.
An electrostatic shield for alleviating the electric field at the end of the coil 1, an inner insulating cylinder 3 provided on the inner peripheral portion of the coil 1, and 3 a, 3 b and 3 c facing the end of the coil 1 from the inner insulating cylinder 3. And an inner insulating flange extending outward.

[0003] Reference numeral 4 denotes an outer insulating barrier composed of a plurality of concentrically provided insulating barriers, 4a and 4b denote outer insulating flanges extending inward from the outer insulating barrier 4, 5 denotes a coil fastening plate for fixing a coil, and 6 denotes a coil fastening plate. A magnetic shield for reducing a leakage magnetic field to the outside of the coil, 7 is an oil guide box for evenly distributing insulating oil in the circumferential direction of the coil 1, and 8 is insulating oil from a cooler (not shown). An oil guide pipe 9 leading to the oil guide box 7 is an oil stopper, which is provided so that insulating oil flows in a zigzag manner between the inner and outer peripheral portions of the coil 1 and the coil itself. Arrows indicate the flow of insulating oil.

[0004] In the conventional DC reactor configured as described above, the coil 1 is connected in series to a DC line via a lead conductor (not shown). DC line voltage, eg 25
A DC high voltage of 0 to 500 (kv) is obtained. Therefore, in order to ensure insulation between these current-carrying parts and the ground, the inner peripheral insulating flanges 3a, 3b, 3c and the outer insulating flanges 4a, 4b made of a press board or the like and the insulating oil flowing into the opposing gap therebetween are provided. Are alternately arranged, and an oil immersion composite insulation configuration is adopted.

The voltage applied between the insulating oil and the press board in the oil-immersed composite insulating structure of the voltage applied to the current-carrying part is as follows:
In the case of AC voltage, the inverse ratio of each dielectric constant (approximately 1: 0.7) is obtained, whereas in the case of DC voltage, the ratio is shared by each specific resistance ratio. The specific resistance ratio can be calculated, for example, as shown in the Institute of Electrical Engineers of Japan, Power and Energy Division Conference No. 594, “Basic Characteristics of DC Insulation in Oil”, such as the temperature at which an insulator is placed and the electric field strength. It changes depending on the condition.
That is, FIG. 5 shows the temperature and electric field characteristics of the volume resistivity of the insulating oil, and FIG. 6 shows the temperature and electric field characteristics of the volume resistivity of the press board. You can see that. In other words, as the temperature changes, the voltage sharing ratio between the insulating oil and the press board increases from 1:10 to 1:
Although it changes like 100, the tendency is that the electric field concentrates on the press board.

In the case of the conventional DC reactor shown in FIG.
Since the electric field is concentrated on the press board as described above,
At both ends of the coil 1, inner circumferential insulating flanges 3a, 3b, 3c extending from the inner circumferential insulating cylinder 3 to the outer circumferential side, and outer insulating barriers 4
The outer insulating flanges 4a and 4b extending from the inner circumferential side to the inner circumferential side are alternately arranged with a gap therebetween, and the insulating oil flows into the gap,
The voltage distribution in which equipotential lines are concentrated on the flange portion is provided, and the electric field in the creeping direction of the flange portion formed of the press board is reduced, thereby improving the DC dielectric strength.

[0007] By the way, the voltage is DC 250 (KV) to 500 (KV),
Energizing current is 1000 (A) -3000 (A), inductance is 0.1 (H)
In high voltage, large capacity DC reactors up to ~ 1 (H),
The heat loss of the coil 1 also becomes a large value of 1000 (KW) to 2000 (KW). Although it is necessary to perform appropriate cooling for such heat loss, in the conventional DC reactor shown in FIG. 4, as indicated by the arrow, the insulating oil is supplied to the coil via the oil guide pipe 8 and the oil guide box 7. An oil feed pump (not shown) is used to cool the insulating oil whose temperature has risen and cool it by a cooler (not shown) such as a radiator and flow it again into the circumferential surface of the coil 1. (Not shown) to circulate the insulating oil. In the coil 1, an oil plug 9
Thereby, the insulating oil flows alternately inside and outside the coil surface without directly rising on the inner and outer circumferences of the coil 1, so that the coil surface can be efficiently cooled.

[0008] As shown in FIG. 4, the coil 1 is installed with its axis substantially vertical. In order to cool the coil 1, insulating oil is supplied to an oil guide box 7 provided below the coil 1.
Flows into the lower part of the coil 1 and, as it flows toward the upper part of the coil 1, absorbs the heat radiation from the coil 1 and gradually rises in temperature.

For example, assuming a standard heat value and a circulating oil amount, the heat value of the coil 1 is 2000 (KW) and the coil 1 of insulating oil is used.
Assuming that the amount of circulating oil in the inside is 10,000 (l / min), the specific gravity of insulating oil is 0.9, and the specific heat of insulating oil is 1.9 (kj / kg
From g), the temperature difference Δθ of the insulating oil between the lower part and the upper part of the coil 1 is calculated to be about 7 degrees as follows. Δθ = 2000 (kw) × 1 (sec) /1.9 (kj / kg ・ deg) × 10000 (l) /
60 (sec) × 0.9 = 7deg Note that the above calculation was made based on the standard heat generation of the coil and the amount of circulating oil.However, for example, the entire amount of circulating oil was not supplied to the coil In such a case, it is easy to assume that the temperature difference between the lower surface and the upper surface of the coil increases in inverse proportion to the oil flow rate on the coil surface. Accordingly, the temperatures of the inner insulating flanges 3a and 3b and the outer insulating flange 4a exposed to the insulating oil passing through the lower surface of the coil 1 become equal to the temperatures of the insulating oil, and the inner insulating flanges 3c located on the lower side of the coil 1 are removed. The temperature is different from that of the outer insulating flange 4b.

On the other hand, as described above, the temperature characteristics of the insulating oil and the volume resistivity (specific resistivity) of the press board are as shown in FIGS. 5 and 6, respectively. The difference in specific resistivity with the board is reduced. Since the voltage sharing between the insulating oil and the press board with respect to the DC voltage becomes their specific resistance ratio, the difference in their specific resistances is reduced, so that the inner peripheral insulating flanges 3a, 3b, The voltage sharing ratio of the outer insulating flange 4a decreases, and the voltage sharing ratio of the insulating oil increases.

By the way, the withstand voltage with respect to the DC voltage is as low as 1/10 of the insulating oil with respect to the press board for the same insulating dimensions. Therefore, as the temperature rises, the voltage sharing of the insulating oil increases due to a decrease in the voltage share of the insulating flanges 3a, 3b, and 4a, which are press boards, and a decrease in the degree of insulation severity. The rate of increase in insulation severity is 10
More than double. As a result, the DC withstand voltage severity of the insulating oil increases rapidly with the temperature rise.For example, the temperature characteristics of the severity of insulation in a press board ratio of 20 to 40%, which is generally used for ordinary oil immersion composite insulation Is as shown in FIG.

Under the condition of high ambient temperature in summer, 50 in FIG.
Since the device is operated in a temperature range of not less than ° C., the pressure resistance of the device is determined by the severity of the insulating oil. In particular, in the vicinity of the insulating oil outflow portion on the upper surface of the coil 1, that is, in the vicinity of the inner circumferential insulating flanges 3a and 3b and the outer insulating flange 4a, the dimension between the coil 1 and the magnetic shield 2 at the ground potential is small and the electric field originally high In addition, since the temperature is the highest, the severeness of the DC withstand voltage is the highest and the insulation becomes the weakest point.

FIG. 8 shows, for example, Japanese Patent Application Laid-Open No. 61-120411.
1 shows another conventional DC reactor device having a configuration in which a lead conductor 14 is led out from an upper end portion of a coil 1. The insulation configuration of the lead conductor 14 is an oil immersion composite insulation configuration in which insulating oil passing through the peripheral surface of the coil 1 flows into the corrugated press board 16 provided on the peripheral surface of the covering insulator 15. . The same reference numerals as those in FIG. 4 indicate the same or corresponding parts. In this conventional device, not only the insulation of the upper part of the coil 1 but also the insulation of the lead conductor 14 increases the temperature of the insulating oil, thereby increasing the severity of the DC withstand voltage. Become.

[0014]

The conventional oil-filled DC equipment such as a DC reactor is configured as described above.
The part where the coil is cooled and exposed to the insulating oil whose temperature has risen, especially the insulation at the coil end or the insulation of the lead conductor, has the problem that the severity of DC withstand voltage increases and the insulation becomes a weak point. there were.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. A first object of the present invention is to suppress the temperature rise of the coil end insulating means so that the DC withstand voltage is less severe. An object of the present invention is to obtain an oil-filled DC device such as a DC reactor that prevents rise.

A second object of the present invention is to provide an oil-filled DC device such as a DC reactor in which a rise in the temperature of a lead conductor insulating portion is suppressed to prevent the DC withstand voltage from increasing in severity. .

A third object of the present invention is to more effectively cool the insulating oil flowing into the coil end insulating means and / or the lead conductor insulating portion, thereby suppressing a rise in temperature at those portions. An object of the present invention is to provide an oil-filled DC device such as a DC reactor in which the degree of DC withstand voltage is prevented from increasing.

[0018]

The oil-filled DC device according to the present invention is provided with means for preventing the insulating oil that has cooled the coil from flowing into the coil end insulating means.

Further, an oil guide path for guiding the insulating oil before cooling the coil to the coil end insulating means is provided in an inner circumferential insulating cylinder provided on the inner circumferential portion of the coil.

Further, there is provided means for preventing the insulating oil that has cooled the coil from flowing into the lead conductor insulating portion.

Further, an oil guide path for guiding the insulating oil before cooling the coil to the lead conductor insulating portion is provided on the outer insulating barrier provided on the outer peripheral portion of the coil.

Further, an oil guide path provided in the inner circumferential insulating cylinder of the coil for guiding the insulating oil before cooling the coil to the coil end insulating means, and a coil provided in the outer insulating barrier to cool the coil to the lead conductor insulating portion. An oil guide path for guiding the previous insulating oil, and a plug provided between the inner peripheral insulating cylinder and the outer insulating barrier to prevent the insulating oil that has cooled the coil from flowing into the coil end insulating means. A plug provided on the outer insulating barrier to prevent the insulating oil that has cooled the coil from flowing into the lead conductor insulating portion.

Further, a first oil circulation path for circulating the insulating oil for cooling the coil, and at least one of the coil end insulation means and the lead conductor insulation section are separated from the first oil circulation path. To circulate the insulating oil flowing into the tank
And a cooling means for cooling the insulating oil in each of the first oil circulation path and the second oil circulation path.

Further, an outer insulating barrier is constituted by a plurality of insulating barriers arranged concentrically with a gap therebetween,
An oil guide path for guiding insulating oil before cooling the coil to the lead conductor insulating portion is provided in a gap between the plurality of insulating barriers.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 shows an oil-filled DC reactor device according to a first embodiment of the present invention, in which 1 is a coil of a DC reactor, and a plurality of disc-shaped coils 1a are vertically arranged at predetermined intervals. It is configured to be stacked. Reference numeral 2 denotes an electrostatic shield provided at an upper end and a lower end of the coil 1, respectively. Reference numeral 3 denotes an inner peripheral insulating cylinder formed of a press board provided at an inner peripheral part of the coil 1, 3a, 3b, and 3c denote the inner peripheral insulating cylinder. An inner peripheral insulating flange made of a press board provided to extend radially outward from the cylinder, 3a,
3b is located at the upper end of the coil 1, and 3c is located at the lower end of the coil 1.

Reference numeral 4 denotes an outer insulating barrier formed of a press board provided on the outer peripheral side of the coil 1, and is formed by concentrically stacking three cylindrical insulating barriers with a gap therebetween. Reference numerals 4a and 4b denote outer insulating flanges made of a press board, each extending from the outer insulating barrier 4 inward in the radial direction. This outer insulating flange 4
a is located at the upper end of the coil 1 and faces the inner peripheral insulating flanges 3a and 3b via a predetermined gap, and the outer insulating flange 4b is located at the lower end of the coil 1 and is located at a predetermined distance from the inner peripheral insulating flange 3c. Opposing each other via a gap.

Reference numerals 101 and 102 denote coils 1 respectively.
DC 250 (KV) to 5
This is coil end insulating means for ensuring insulation between the coil 1 to which 00 (KV) is applied and the ground. Then, the coil end insulating means 101 is provided with the inner peripheral insulating flanges 3a, 3b.
And the outer insulating flange 4a and the insulating oil flowing into the gap between them are arranged in an oil immersion composite insulating structure in which the coil end insulating means 102 is provided with the inner peripheral insulating flange. An oil immersion composite insulation structure is provided in which the insulating oil 3c and the insulating oil flowing into the outer insulating flange 4b and the gap between them are alternately arranged.

Reference numerals 5a and 5b denote coil fastening plates above and below the coil 1 for fastening and fixing the coil 1, and 6a,
6b is a magnetic shield for reducing the leakage magnetic field to the outside of the coil 1, 7 is an oil guide box provided below the coil tightening plate 5b, and a plurality of oil guide holes provided on the coil tightening plate 5b. The insulating oil is evenly distributed in the circumferential direction from 50 to the peripheral surface of the coil 1 via the coil end insulating means 102. Reference numeral 8 denotes an oil guide pipe for guiding insulating oil from a cooler (not shown) to the oil guide box 7. 9a, 9b,
9c is an oil stopper provided between the outer peripheral portion of the coil unit 1a and the inner peripheral surface of the outer insulating barrier 4 and between the inner peripheral portion of the coil unit 1a and the outer peripheral portion of the inner peripheral insulating cylinder 3, respectively. The insulating oil flows alternately inside and outside the surface of the coil unit 1a without raising the inner and outer circumferences of the coil 1 as it is to cool the coil 1 efficiently.

Reference numerals 26a and 26b denote oil guide holes provided above and below the inner peripheral insulating cylinder 3, respectively, and together with the inner peripheral space of the inner peripheral insulating cylinder 3, form an oil guiding path. ,
The insulating oil before cooling the coil 1 that has flowed into the coil end insulating means 102 from the oil guide box 7 through the oil guide hole 50 is partially flowed and directly flows into the coil end insulating means 101. Reference numerals 27a and 27b denote oil guide holes provided at the lower portion of the outer insulating barrier 4, and allow the insulating oil flowing from the oil guide box 7 through the oil guide holes 5 to partially flow to the outer insulating barrier 4.
Flow into the gap between each other. The oil guide holes 27a, 27b
Forms an oil guide path for directly guiding the insulating oil before cooling the coil 1 to the insulating portions of the lead conductors 14a and 14b described later together with the gap between the outer insulating cylinders 4.

Reference numeral 28a denotes a dam stopper provided between the outer surface of the inner insulating cylinder 3 and the inner surface of the electrostatic shield 2, and 28b denotes
This is a dam stopper provided between the inner surface of the outer insulating barrier 4 and the outer peripheral surface of the insulating barrier 28c fixed to the electrostatic shield 2. The dam stoppers 28a and 28b and the insulating barrier 28c serve as a means for preventing the insulating oil whose temperature has increased by cooling through the peripheral surface of the coil 1 from flowing into the coil end insulating means 101. Make up.

Reference numerals 29a and 29b denote dam stoppers provided between the outer insulating barriers 4, and the insulating oil, which has cooled the temperature of the coil 1 through the peripheral surface thereof and increased in temperature, is supplied to the gap between the outer insulating barriers 4. To prevent inflow. Reference numeral 60 denotes an oil discharge hole provided at an upper portion of the outer insulating barrier 4 for discharging the insulating oil passing through the peripheral surface of the coil 1 to the outside of the outer insulating barrier 4.

14a is a lead conductor drawn out from the upper part of the coil 1, 17a is a lead taping provided on the peripheral surface of the lead conductor 14a, and 15a is a lead taping 1
An inner lead insulating barrier made of a press board surrounding the outer peripheral portion of 7a via an oil gap 19a, and an outer lead insulating barrier 16a surrounding the inner lead insulating barrier 15 through an oil gap 18a. The lead conductors 14a, 1
4b is applied with a DC high voltage, but as described above, the inner and outer lead insulation barriers 15a, 16a, 15b, 16b,
The insulating oil flowing into the oil gaps 18a and 19a and the lead taping 17a and 17b are insulated from the ground by the oil immersion composite insulation alternately arranged.

FIG. 2 shows the details of the structure of the portion where the lead conductor 14b penetrates from the inside of the outer insulating barrier 4 and is led out to the outside. The hole 41 penetrates. The through hole 41 is sealed by the sealing insulating plate 30 so that the insulating oil inside the outer insulating barrier 4 does not flow into the gap between the outer insulating barriers 4. Inner lead insulation barrier 15
b is a through hole 42 of the outer insulating barrier 4 at its base.
And the outer lead insulation barrier 16b
Is fixed around the through hole 43 of the outer insulating barrier 4 at its base.

The inner and outer lead insulating barriers 15
oil gap 18b between b and 16b, and lead taping 17b
An oil gap 19b between the inner lead insulating barrier 15b and the inner lead insulating barrier 15b is filled with a honeycomb-like filling supporting material (not shown) to support them. The insulating oil is provided in the through holes 42 of the outer insulating barrier 4,
43 flows into the oil gap and insulates and cools the lead conductor 14b. The lead conductor 14a and its oil-immersed composite insulating structure are formed in the same manner as in FIG. 2, but are drawn out of the outer insulating barrier 4 at a part circumferentially different from the part from which the lead conductor 14b is drawn out. ing.

In FIG. 1, reference numeral 20 denotes a main body storage tank of a DC reactor, and reference numerals 21a and 21b denote lead conductors 14 respectively.
a bushing which is connected to a and 14b and serves as a lead terminal of the DC reactor; 22 is a terminal storage duct for storing a part of the bushings 21a and 21b and the ends of the lead conductors 14a and 14b and their insulating portions; An inflow pipe 24 for guiding the insulating oil from a cooler (not shown) for cooling the insulating oil to the oil guide pipe 8. A return pipe 24 guides the insulating oil from inside the main body tank 20 to the cooler. Main piping, 2
Reference numeral 5 denotes a return branch pipe for guiding the insulating oil from the inside of the terminal storage duct 22 to the cooler via the return main pipe 25.

The oil-filled DC reactor device thus constructed is connected to the bushings 21a and 21b, for example, to connect a DC 2
It is operated by being connected to a DC line of 50 (KV) to 500 (KV), but the conduction current is 1000 (A) and the inductance is 1 (H).
In a high-voltage, large-current DC reactor, the heat loss of the coil 1 is also as large as 1000 (KW) to 2000 (KW). Insulating oil is circulated to insulate and cool the coil 1. The insulating oil cooled by a cooler such as a radiator (not shown) is supplied to an oil feed pump (not shown).
Thus, the oil flows from the inflow side pipe 23, the oil guide pipe 8, and the oil guide box 7 into the coil end insulating means 102 at the lower end of the coil 1 through the oil guide hole 50, and further flows into the lower peripheral surface of the coil 1. .

Then, it flows along the surface of the coil unit 1a as shown by the solid arrow, and flows upward while cooling the coil 1 which has generated heat as described above. Thereafter, the insulating oil flows from the oil discharge hole 60 to the outside of the outer insulating barrier 4, is further guided from the main body storage tank 20 to a cooler (not shown) by the return main pipe 24, and is cooled by the cooler. And it is again guided to the inflow side piping 23 from a cooler.

The insulating oil whose temperature has risen after cooling the coil 1 is blocked by the dam stoppers 28a and 28b and the insulating barrier 28c, and is prevented from flowing into the coil end insulating means 101. On the other hand, the insulating oil cooled by the cooler
After flowing into the coil end insulating means 102 at the lower end of the coil 1 from the oil guide box 7, the oil flows from the oil guide hole 26 b of the inner circumferential insulating cylinder 3 to the inner circumferential space of the inner circumferential insulating cylinder 3 as indicated by a wavy arrow. The oil flows into the coil end insulating means 101 from the oil guide hole 26a.

As a result, the coil end insulating means 101
The coil 1 is always filled with low-temperature insulating oil before cooling, and the temperature does not rise regardless of the heat generated by the coil 1. Therefore, since the voltage sharing ratio of the insulating oil having a low dielectric strength basically does not increase, the severity of the DC withstand voltage of the coil end insulating means 101 can be reduced. The coil end insulating means 102 at the lower part of the coil always receives the insulating oil cooled by the cooler from the oil guide box 7 and the coil end insulating means 101 at the upper part of the coil.
Similarly, the temperature is kept low, and the severity of the insulation is kept low.

On the other hand, the insulating oil flowing from the oil guide box 7 into the coil end insulating means 102 below the coil is supplied from the cooler to the oil guide hole 27 provided at the lower end of the outer insulating barrier 4.
a, 27b, the outer insulating barrier 4 as shown by the wavy arrow
2, and into the oil gaps 18b, 19b that make up the oil immersion composite insulation of the lead conductor 14b, as best seen in FIG.
Insulate and cool b. The insulating oil that has flowed into the oil gaps 18b and 19b flows out into the terminal storage duct 22 and is returned to the return branch pipe 2.
5 returns to the cooler by the return main pipe 24 (not shown) and is cooled. The lead conductor 14a is also insulated and cooled by insulating oil in the same manner as the lead conductor 14b.

The insulating oil that has cooled the coil 1 is prevented from flowing into the gap between the outer insulating barriers 4 by the dam stoppers 29 a and 29 b provided on the outer insulating barrier 4 and the sealing insulating plate 30. And therefore lead conductor 14
a, 14b oil immersion composite insulation oil gaps 18a, 18b, 19a,
It does not flow into 19b. Therefore, the temperature of the oil immersion composite insulating portion of the lead conductor is always kept low irrespective of the heat generation of the coil 1, and the voltage sharing ratio of the insulating oil having a low dielectric strength basically does not increase. Severity can be kept low.

According to the first embodiment described above, the insulating oil whose temperature has risen due to cooling of the coil does not flow into the coil end insulating means and the lead conductor insulating portion. As a result, the severity of the DC withstand voltage of the insulating portion is suppressed to a low level, and a highly reliable oil immersion DC reactor device can be obtained. Further, since the severity of the DC withstand voltage of the insulating portion can be suppressed low, the insulating dimensions can be reduced, and the device can be reduced in size and cost.

Embodiment 2 In the first embodiment, the insulating oil from the cooler is partially flowed into the coil end insulating means and the lead conductor insulating portion before flowing into the peripheral surface of the coil, and then the separated insulating oil is again flown. Although the coil is merged with the cooled insulating oil and circulated to the cooler, a cooling path for the coil-cooling insulating oil for cooling the coil, the coil end insulating means and the insulating portion flowing into the lead conductor insulating portion are cooled. And the circulation path of the insulating oil for use may be separated and independent, and a cooler for cooling the insulating oil may be separately provided in each of the circulation paths.

FIG. 3 shows an embodiment of the present invention.
Reference numeral 1 denotes a cooler for cooling insulating oil for cooling an insulating portion, which is provided separately from a cooler (not shown) for cooling the insulating oil that flows into the peripheral surface of the coil 1 and cools the coil. It has a cooling fan 310. 32 is an oil feed pump for circulating insulating oil for cooling the insulating portion, 33a is an inflow pipe for guiding the insulating oil for cooling the insulating portion, and 34a is an insulating oil for cooling the insulating portion provided in the main body storage tank 20. Oil guiding pipes for guiding oil guiding holes 27a and 27b provided in the outer insulating barrier 4.
, And further to an oil guide hole 26b provided in the inner peripheral insulation 3 or the like. An oil guide pipe 34b communicates with the gap of the coil end insulating means 101, and guides the insulating oil to the outside of the main body storage tank 20. An oil guide pipe 33b is connected to the oil guide pipe 34b and the terminal storage duct 22 to form an insulating portion. It is a return pipe for returning the insulating oil for cooling to the cooler 31.

The circulation path of the insulating oil for cooling the coil 1 includes the inflow side pipe 23, the oil guide box 7, the oil guide hole 50 provided in the coil tightening plate 5b, the coil end insulating portion 102, and the peripheral surface of the coil 1. It comprises a space, an oil discharge port 60 provided in the outer insulating barrier 4, an inner space of the main body storage tank 20, the return main pipe 24, and a cooler (not shown) for cooling insulating oil for cooling the coil. The circulation path of the insulating oil for cooling the coil 1 is completely separated and independent from the circulation path of the insulating oil for cooling the insulating part. The other configuration is the same as that of the first embodiment in FIG. 1, and the same or corresponding portions are denoted by the same reference numerals as in FIG.

According to the second embodiment, the circulation path of the insulating oil flowing into the coil end insulating means 101 and the insulating portion of the lead conductors 14a and 14b is separated from the circulation path of the insulating oil that cools the coil 1. Since it is independent, its circulation path does not include a heating part such as a coil. For this reason, it is only necessary to cool only the amount of heat that enters and enters the coil end insulating portion 101 and the insulating portions of the lead conductors 14a and 14b.
With the cooler 31 having a small cooling capacity of about W), the temperature can be further lowered than that of the insulating oil for cooling the coil. As a result, the degree of insulation of the coil end insulating portion and the lead conductor insulating portion can be suppressed to a lower level, and the DC dielectric strength can be further improved as compared with the first embodiment.

In the second embodiment shown in FIG. 3, the forced cooling system in which the cooling oil for cooling the insulating portion is forcibly cooled by the cooler 31 provided with the cooling fan 310 and the oil feed pump 32 is described above. Since a small cooling capacity is sufficient, the cooling fan 310 of the cooler and the oil feed pump 32 may be omitted, and a natural cooling system using a cooler including only a radiation fin may be used.

Embodiment 3 In the first and second embodiments, the oil-immersed DC reactor device has been described as the oil-immersed DC device, but the converter-side (DC side) coil of the transformer for a transformer also operates with DC charging. Therefore, it is a matter of course that the insulation configuration of the converter side coil of the converter transformer can be configured in the same manner as the embodiment of FIGS.

[0049]

Since the present invention is configured as described above, the following effects can be obtained.

Since means for preventing the insulating oil that has cooled the coil from flowing into the coil end insulating means is provided, the insulating oil whose temperature has increased by cooling the coil flows into the coil end insulating means. Therefore, the temperature of the insulating portion is kept low, the severity of the DC withstand voltage can be suppressed low, and an oil-filled DC device having highly reliable insulation characteristics can be obtained. In addition, since the severity of the DC withstand voltage of the insulating portion can be suppressed to a low level, the size of the insulation can be reduced, and a small and inexpensive device can be obtained.

Since the oil guide path for guiding the insulating oil before cooling the coil to the coil end insulating means without passing through the coil peripheral surface is provided in the inner circumferential insulating cylinder, the temperature is always low to the coil end insulating means. Insulating oil can be flowed in, the temperature of the coil end insulating means can be kept lower, the severity of DC withstanding voltage can be kept lower, and oil-filled DC equipment with more reliable insulation properties can be obtained. it can. Further, since the severity of the DC withstand voltage of the insulating portion can be suppressed to a low level, the insulating dimensions can be reduced and a smaller and less expensive device can be obtained.

Since the means for preventing the insulating oil having cooled the coil from flowing into the lead conductor insulating portion is provided, the insulating oil whose temperature has risen by cooling the coil into the lead conductor insulating portion does not flow. Therefore, the temperature of the insulating portion is kept low, the severity of the DC withstand voltage can be suppressed low, and an oil-filled DC device having highly reliable insulation characteristics can be obtained. In addition, since the severity of the DC withstand voltage of the insulating portion can be suppressed to a low level, the size of the insulation can be reduced, and a small and inexpensive device can be obtained.

Since an oil guide path is provided in the outer insulating barrier to guide the insulating oil before cooling the coil to the lead conductor insulating portion without passing through the coil peripheral surface, the insulating oil having a low temperature is always supplied to the lead conductor insulating portion. It is possible to obtain an oil-filled DC device having a more reliable insulation characteristic by keeping the temperature of the lead conductor insulating portion lower, lowering the severity of the DC withstand voltage, and lowering the severity. Further, since the severity of the DC withstand voltage of the insulating portion can be suppressed to a low level, the insulating dimensions can be reduced and a smaller and less expensive device can be obtained.

An oil guide path provided on the inner peripheral insulating tube and guiding the insulating oil before cooling the coil to the coil end insulating means without passing through the peripheral surface of the coil, and a lead conductor insulating section provided on the outer insulating barrier. An insulating oil passage that guides the insulating oil before cooling the coil without passing through the peripheral surface of the coil and the insulating oil that is provided between the inner circumferential insulating cylinder and the outer insulating barrier and cools the coil to the coil end insulating means. And a plug provided in the outer insulating barrier to prevent the insulating oil that has cooled the coil from flowing into the lead conductor insulating portion, so that the coil end insulating means and Low-temperature insulating oil can always flow into the lead conductor insulating part, and since the coil is cooled, the heated oil does not flow into the coil end insulating means and the lead conductor insulating part. Edge insulation Maintaining even lower stage and the temperature of the lead conductor insulating part, it is possible to suppress lower the severity of the DC withstand voltage, it is possible to obtain a further oil-filled direct current device having a highly reliable insulating properties. Further, since the severity of the DC withstand voltage of the insulating portion can be suppressed to a low level, the insulating dimensions can be reduced, and a more compact and inexpensive device can be obtained.

The first for circulating the insulating oil for cooling the coil
And a second oil circulation path which is separated from the first oil circulation path and circulates insulating oil flowing into at least one of the coil end insulating means and the lead conductor insulating means. Since the cooling means for cooling the insulating oil is provided in each of the first oil circulation path and the second oil circulation path, the second oil circulation path has no heat-generating portion such as a coil, and has a coil end portion. It is possible to further reduce the severity of the DC withstand voltage of the insulating means and / or the lead conductor insulating portion, and to obtain an oil-filled DC device having more reliable insulation characteristics. Further, since the severity of the DC withstand voltage of the insulating portion can be further reduced, the size of the insulating layer can be reduced, and a more compact and inexpensive device can be obtained.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of an oil-filled DC reactor device showing a first embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a part of a lead conductor and an insulating part thereof according to the first embodiment of the present invention;

FIG. 3 is a partial cross-sectional view of an oil-filled DC reactor device according to a second embodiment of the present invention.

FIG. 4 is a partial sectional view of a conventional oil-filled DC reactor device.

FIG. 5 is a graph showing temperature / electric field characteristics of volume resistivity of insulating oil.

FIG. 6 is a graph showing a temperature / electric field characteristic of a volume resistivity of a press board.

FIG. 7 is a graph showing the temperature characteristics of the severity of the electric field between the press board and the insulating oil.

FIG. 8 is a partial sectional view of a conventional oil-filled DC reactor device.

[Explanation of symbols]

1 coil, 1a coil unit, 2 electrostatic shield, 3
Inner peripheral insulating cylinder, 3a inner peripheral insulating flange, 3b inner peripheral insulating flange, 3c inner peripheral insulating flange, 4 outer insulating barrier, 4a outer insulating flange, 4b outer insulating flange,
5a coil tightening plate, 5b coil tightening plate, 6a magnetic shield, 6b magnetic shield, 7 oil guide box, 8
Oil guide pipe, 9a oil tap, 9b oil tap, 9c oil tap, 14a
Lead conductor, 14b Lead conductor, 15a Lead insulation barrier, 15b Lead insulation barrier, 16a Lead insulation barrier, 16b Lead insulation barrier, 17a Lead taping, 17b Lead taping, 18a Oil gap, 18
b oil gap, 19a oil gap, 19b oil gap, 20 body storage tank, 21a bushing, 21b bushing, 22
Terminal storage duct, 23 inlet pipe, 24 return main pipe, 25 return branch pipe, 26a oil guide hole, 26b oil guide hole, 27a oil guide hole, 27b oil guide hole, 28a dam stopper, 28b dam stopper, 28c insulation barrier , 29a
Dam stopper, 29b dam stopper, 30 sealing insulating plate,
31 cooler, 310 cooling fan, 32 oil feed pump, 33a inlet side pipe, 33b return pipe, 34a
Oil guide pipe, 34b oil guide pipe, 41 through hole, 42
Through-hole, 43 through-hole, 50 oil guide hole, 101 coil end insulating means, 102 coil end insulating means.

Claims (7)

[Claims] 1. A coil to which a DC voltage is applied, and a coil end insulating means located at an end of the coil to insulate the coil, wherein an insulating oil is provided on the peripheral surface of the coil and the coil end insulating means. For cooling and insulating the coil by providing a means for preventing the insulating oil that has cooled the coil from flowing into the coil end insulating means. DC equipment. 2. An inner peripheral insulating cylinder and an outer insulating barrier are respectively provided on an inner peripheral part and an outer peripheral part of the coil, and the insulating oil before cooling the coil is supplied to the inner peripheral insulating cylinder without passing through the peripheral surface of the coil. 2. The oil-filled DC device according to claim 1, wherein an oil guide path leading to the end insulating means is provided. 3. A coil, a lead conductor for applying a DC voltage to the coil, and a lead conductor insulating portion for insulating the lead conductor, wherein insulating oil flows into the peripheral surface of the coil and the lead conductor insulating portion. Wherein the coil and the lead conductor are cooled and insulated, and wherein means for preventing the insulating oil that has cooled the coil from flowing into the lead conductor insulating portion is provided. machine. 4. An inner insulating tube and an outer insulating barrier are provided on an inner peripheral portion and an outer peripheral portion of the coil, respectively, and the insulating oil before cooling the coil is supplied to the outer insulating barrier without passing through the peripheral surface of the coil. 4. The oil-filled DC device according to claim 3, wherein an oil guide path leading to the insulating portion is provided. 5. A coil, a coil end insulating means located at an end of the coil for insulating the coil, a lead conductor for applying a DC voltage to the coil, and a lead conductor insulating part for insulating the lead conductor Wherein the insulating oil flows into the peripheral surface of the coil and the coil end insulating means and the lead conductor insulating portion to cool and insulate the coil and the lead conductor. An inner insulating cylinder and an outer insulating barrier respectively provided in the section,
An oil guide path provided in the inner insulating cylinder and guiding the insulating oil before cooling the coil to the coil end insulating means without passing through a peripheral surface of the coil; and the lead conductor insulating provided in the outer insulating barrier. Means for guiding the insulating oil before cooling the coil to the means without passing through the circumferential surface of the coil, and the coil to the coil end insulating means provided between the inner circumferential insulating cylinder and the outer insulating barrier. A plug that prevents the insulating oil that has cooled the coil from flowing in, and a plug that is provided on the outer insulating barrier and that prevents the insulating oil that has cooled the coil from flowing into the lead conductor insulating means. Oil-filled DC equipment. 6. A first oil circulation path for circulating insulating oil for cooling a coil, and at least one of said coil end insulation means and said lead conductor insulation means separated from said first oil circulation path. A second oil circulation path for circulating the insulating oil flowing into the first oil circulation path, and cooling means for cooling the insulating oil in each of the first oil circulation path and the second oil circulation path. The oil-filled DC device according to claim 5. 7. The outer insulating barrier is composed of a plurality of insulating barriers concentrically arranged with a gap therebetween, and the oil guide path for guiding the insulating oil before cooling the coil to the lead conductor insulating portion is formed of the plurality of insulating barriers. The oil-filled DC device according to any one of claims 4 to 6, wherein the oil-filled DC device is provided in a gap between the insulating barriers.