JPS58182453A - Feeder for sealing oil of rotary electric machine - Google Patents

Abstract

PURPOSE:To ensure a fixed quantity of more of cooled oil supplied to a sealing oil tank, and to prevent a temperature rise of oil in the sealing oil tank by setting up a bypass circuit between the discharge piping of a sealing oil pump on the upstream side of a differential pressure regulating valve and an air extracting tank. CONSTITUTION:The seal ring of a generator 1 is supplied with sealing oil in the sealing oil tank 4 through the differential pressure regulating valve 21 and a feed pipe by the sealing oil pump 19, and sealing oil branching to the outside of the generator is collected into the air extracting tank 5, and returned into an oil tank 9. Oil in the oil tank 9 is cooled by a cooler 11, and resupplied to a bearing device 2 while one part is forwarded into the sealing oil tank 14. The bypass circuit 25 through a closing device 26 and a bypass valve 27 is set up between the discharge piping 20 of the sealing oil pump 19 on the upstream side of the differential pressure regulating valve 21 and the air extracting tank 5, the quantity of oil corresponding to the quantity of reduction of the quantity of sealing oil supplied to a sealing 3 is forwarded directly into the air extracting tank 5 from the pump discharge pipe 20, and the sealing oil tank 14 is supplied with cooled sealing oil in the same quantity as normal operation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a hydrogen gas cooled turbine generator,
[Technical Background of the Invention] In general, for example, in a turbine generator etc. that is cooled by sealing hydrogen gas inside the machine, A shaft seal is provided to prevent hydrogen gas from leaking into the atmosphere from the shaft penetrating portion, and sealing oil is supplied to the shaft seal to seal the hydrogen gas. It is a system diagram showing a conventional sealed oil supply device for supplying oil, in which (1) is a turbine generator, (2) is a bearing device of the turbine generator (1), and (3) is a turbine generator ( 1) A seal ring for sealing the hydrogen gas sealed inside, (4) a seal oil supply pipe that supplies seal oil to the seal ring (3), and (5) a seal oil supply pipe that supplies seal oil to the seal ring (3). The air extraction tank (6) collects and temporarily stores sealing oil and extracts the air contained in the sealing oil.
1) An expansion tank for collecting and storing the sealing oil diverted to the inside of the machine (hydrogen gas 1) and extinguishing bubbles caused by hydrogen gas mixed in the sealing oil, (7) is an expansion tank (6) and an air extraction tank. (5)
This is a float trap tank installed in the seal oil return line that communicates with the hydrogen gas cuff float trap tank (
A valve (7a) is provided that interlocks with the float to prevent the oil from flowing out of the machine through the air extraction tank (5) due to the drop in the oil level in (9), through the return pipe (8). Collect the sealed oil that has been vented in the air extraction tank (5) and simultaneously supply it to the bearing device (2) of the turbine generator (1) fI4fv#
It is an oil storage tank that stores oil, and OI uses the oil in the oil storage tank (9) as bearing lubricating oil, and the bearing-lubricating oil supply pipe c! The oil is sent to the bearing device (2) through the diaphragm, or as seal oil through the conduit θ'
! Sealing oil tank (1, 41) that stores sealing oil via J
cIl is a cooler that cools the bearing lubricating oil or seal oil (1η is a spray nozzle (15a) in the seal oil tank α via the conduit αe).

(15b) is a vacuum pump for vacuum degassing water, hydrogen gas, air, etc. contained in the sealing oil sprayed by (II), which sends the sealing oil in the sealing oil tank α◆ to the seal ring (3). The sealed oil pump (2) is a pressure regulating valve installed on the discharge pipe (A) of the sealed oil pump 01, and a part of the discharge amount of the sealed oil pump (II) is transferred to the recirculation circuit (to). The oil is returned to the 0 fathom of the sealed oil tank through the 0 fathom, and the discharge pressure of the sealed oil pump α is adjusted to a constant level.
By increasing or decreasing the amount of sealing oil to the sealing ring (3) of the turbine generator (1), the pressure of the sealing oil supplied to the sealing ring (3) can be constantly adjusted to the hydrogen gas 2 sealing pressure inside the machine. The pressure detection tube (21a) is a differential pressure regulating valve provided to maintain a constant pressure high.

(:ztb) The amount of sealing oil supplied to the first sealing oil supply pipe (4) is automatically adjusted according to the respective pressure signals introduced at 4. When the pump (11) is operated, the seal oil in the seal oil tank 04 is sent out by the seal oil pump 0, and the seal oil supply pipe (4
) through the turbine generator (11 seal rings (3
). The sealing oil supplied to the seal ring (3) is applied to the inner circumference of the seal ring (3) and the turbine generator (1).
Form an oil film between the outer circumference of the main shaft of 1 and seal the hydrogen gas inside the machine while dividing the flow into the inside of the machine (hydrogen gas side) and the glue outside the machine (air side). By cooling the inside of the device (2) consisting of a lubricating oil supply pipe (2) in a separate system, the oil mixes with the bearing lubricating oil whose temperature has risen and is discharged from the bearing device (21), and is discharged from the air extraction tank (21). 5).On the other hand, the sealing oil diverted to the hydrogen side is sent to the expansion tank (6).
) and is further collected into the air extraction tank (5) via a float trap tank (7) provided to prevent hydrogen gas from escaping. After extracting the air mixed in the bearing device (2), the oil in the oil storage tank (9), which has reached this high temperature (consistently about 55-60°C), is returned to the oil storage tank (9). The oil is pumped out by the oil tank pump Ql, and the oil is
Cooled to tqi constant temperature (usually 40°C) by 0υ,
The bearing lubricating oil supply pipe (to) supplies it again to the bearing [t (21). To the west, a part of the oil cooled by the cooler θυ is supplied as sealing oil to the sealing oil tank via the conduit u3 and the Sugeray nozzle (lSa). 04) This sealed oil tank (141) is equipped with a valve (131) linked to a float so that the oil level is always constant. An amount of sealing oil equal to the amount of sealing oil supplied to the seal ring (3) is supplied to the sealing oil amount/r041. If it contains air, etc., the oil that is diverted to the inside of the machine (hydrogen gas open) at the seal ring (3) will separate the humid air, reducing the purity of the hydrogen gas inside the machine and causing the turbine to 111
! Since the efficiency of the machine (1) is low, it is necessary to supply deaerated oil. Therefore, the inside of the sealed oil tank 0υ is always kept in a vacuum by a vacuum pump (1'/l), and the sealed oil In such surface-mounted seal oil supply equipment, the seal ring (
The sealing oil supply pressure in section 3) is normally always higher than the in-machine hydrogen gas pressure by a certain pressure (usually 0.5 to G). Therefore, the gap, that is, the oil film formed between the inner periphery of the seal ring (3) and the outer periphery of the main shaft of the turbine generator (1) increases and decreases in proportion to the rotational speed of the main shaft of the turbine generator (1). Since the oil flow resistance inside the seal ring (3) changes depending on the temperature of the supplied sealing oil, in order to keep the pressure of the supplied sealing oil constant, The differential pressure regulating valve Qυ delivers sealing oil commensurate with the oil flow resistance at the seal ring (3) at the rotational speed of the main shaft and the temperature of the supplied sealing oil. On the other hand, a part of the oil discharged from the sealing oil pump OI is always returned to the sealing oil tank 0 through the pressure regulating valve die, and the pressure of the oil discharged from the sealing oil pump (11) is maintained constant. By recirculating the sealing oil through the spray nozzle (15b), it is ensured that the sealing oil is sufficiently degassed. The temperature of the oil in tank 04 will rise, but in normal operation, the amount of sealing oil supplied to the seal ring (3) and the amount of cooler a
The cooled oil (by υ) is supplied from the oil storage tank (9) to the sealed oil tank 041 via the conduit 03, and a sufficient amount is ensured so as not to cause a large temperature rise.

[Problems with background technology]

However, turning operation (
During low-speed rotation) or when stopped, the seal ring (
3), the amount of recirculated oil returned from the pressure regulating valve to the sealing oil tank 64 increases, increasing the amount of sealing oil supplied during steady operation and cooling with the cooler 0υ. The balance with the amount of sealing oil supplied to the sealing oil tank shaft cannot be maintained, and the temperature of the oil in the sealing oil tank I increases. Particularly in large-capacity turbine generators, the difference in sealing oil supply amount during rated operation and during turning operation or stoppage can be around 10 times, and the oil temperature rises due to the increase in the amount of recirculated oil mentioned above. In addition, there was a problem that the sealed oil pump OIO could not be operated for a long time.
As the amount of sealing oil supplied to the seal ring (3) decreases,
When the amount of sealing oil supplied to the sealing oil tank I becomes extremely small, the opening of the float valve 03 provided in the sealing oil tank (141) will be operated at a very small opening close to the sealed state. In response to fluctuations in the oil level in the oil tank,
The float valve (13), which opens and closes in conjunction with the oil level float (13g), has poor followability of the opening, making oil level control unstable, and vibrations called chattering occur in the float valve 031 itself. Then, there was a problem.

[Purpose of the invention]

The present invention prevents the oil temperature from rising while the rotating electric machine is stopped and during turning operation by always ensuring a certain amount or more of cooled sealing oil supplied to the sealing oil tank. The operation of the float valve is stable and highly reliable! An object of the present invention is to provide a sealing oil supply device for a rotating electrical machine. In order to prevent this, there is a sealing oil tank and a sealing oil pump that supply sealing oil to the shaft seal portion, a pressure regulating valve provided at the discharge of this sealing oil pump, and a pressure control valve that controls the pressure of the supplied sealing oil to a predetermined pressure. a differential pressure regulating valve for maintaining the pressure higher than the pressure of the cooling gas, and an air extraction tank provided in the circuit for returning from the shaft seal and storing the sealing oil that returns from the shaft seal after being released to the atmosphere. , an oil storage tank that collects the evacuated sealed oil from this air extraction tank, and an oil storage tank that sends the oil in this oil storage tank to a cooler via an oil storage tank pump, cools it to a predetermined temperature, and then sends it again to the sealed oil tank. In a sealing oil supply device for a rotating electrical machine comprising a conduit, a bypass circuit is provided from the upstream side of the differential pressure regulating valve to the air extraction tank via a tightening device and a bypass valve, so that the sealing oil is supplied to the sealing oil tank. [Embodiments of the Invention] Embodiment 1 A first embodiment of the present invention will be described below with reference to FIG. 2. . In Fig. 2, the same parts as in Fig. 1 are designated by the same reference numerals, and their explanations are omitted. This is a bypass circuit that communicates the discharge piping (A) and the air extraction tank (5) with a pipe, and 2 is a tightening device installed on this bypass circuit (4), or the opening/closing of the bypass circuit (C). It is a bypass valve that performs the following.Other than the above, in this Fig. 2, there is an arrow expansion tank (6), a float trap tank (7), and a pressure detection pipe (21m).

(21b) etc. are not shown for the sake of simplicity, but these are also arranged and are the same as shown in FIG.

Next, the operation will be explained.0 During normal operation of the turbine generator (11), the bypass valve of the bypass circuit (c) is closed, and the amount of sealing oil sent out from the oil pump a1 is sealed as described above. The oil is supplied to the sealing ring (3) via the oil supply pipe (4), returns to the oil storage tank (9) via the air extraction tank (5), and is cooled in an amount equal to the amount supplied to this sealing ring (3). The oil is the guide! (
121, and is supplied to the sealed oil tank a fathom,
When the turbine generator (1) is stopped or turning, the bypass valve is opened, and the tightening device (c) with an oriice mechanism restricts the flow of excessive oil while closing the seal ring (3). From K, an amount of oil commensurate with the decrease in the amount of sealing oil supplied to ) is sent directly from the pump discharge pipe to the air extraction tank (5) and returned to the oil storage tank (9).
The same amount of cooled sealing oil as during normal operation is supplied to sealing oil tank a◆, and the valve opening of float valve a1 is also maintained at the same level as during normal operation, so the operation of float valve I is Malfunctions and increases in oil temperature in the sealed oil tank can be avoided.

Example 2 Next, a second example will be explained with reference to FIG. The example uses the on-off valve @ used in Figure 2 as an automatic valve (
), and further install a flow rate relay SW in the seal oil supply pipe (4) on the downstream side of the differential pressure regulating valve Qυ, and apply a detection signal corresponding to the flow rate of this flow rate relay (to) to 19, Signal circuit (
This is a book in which the automatic valve (c) is opened and closed via the valve (to)), and the rest is the same as in the first embodiment.

Next, the effect will be explained.

The flow rate relay - indicates that the amount of sealing oil supplied to the seal ring (3) is below a certain value and exceeds the limit value for temperature rise due to an increase in the recirculation flow rate returned from the so-called pressure regulating valve (c) to the sealing oil tank Q4. This flow rate relay detects when the sealing oil supply amount at the point in time or the sealing oil supply amount at the time when chattering starts due to a decrease in the amount of oil passing through the float valve 00 is greater. By opening the automatic valve (by a signal) and bypassing a portion of the sealed oil amount to the air extraction tank (51II), automation through continuous monitoring can be achieved, increasing the reliability of operation. It should be noted that the present invention is not limited to the embodiments described above and shown in the drawings, but can of course be practiced with various modifications without changing the gist thereof. As described above, according to the present invention, the oil temperature in the sealing oil supply device rises due to a decrease in the amount of sealing oil when the rotating electric machine is stopped or turning operation, making operation impossible, and the sealing oil This is a highly reliable sealing oil supply for rotating electric machines that can solve problems such as chattering caused by the small opening of the float valve in the tank with a relatively simple device and at a low cost, allowing for stable operation. equipment can be provided.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing a conventional seal oil supply device for a rotating electrical machine, and FIGS. 2 and 3 are system diagrams showing first and second embodiments of the seal oil supply device for a rotating electrical machine according to the present invention. A certain C town 1... Turbine generator which is a rotating electric machine 2... Seal ring 5 which is a shaft seal part... Air extraction tank 9.
...Oil storage tank 10...Oil storage tank pump 11...Cooler 12...Conduit 14...Oil tank 19...Oil pump η...Differential pressure wI4 valve n
・・・Pressure control valve 6...ノ(Inno(s) circuit...
...Tightening device nail...〕(Inox valve path...
・Automatic valve 9...Flow relay agent Patent attorney Inoue - Male 1st figure? / L0tqlδ Figure 2 Figure 3

Claims (1)

[Scope of Claims] A seal oil tank and a seal for supplying sealing oil to a shaft seal portion of a rotating electric machine having a cooling gas sealed therein in order to prevent the cooling gas from leaking to the outside. an oil pump, a pressure regulating valve provided on the discharge side of the sealed oil pump, a differential pressure regulating valve for controlling the pressure of the supplied sealing oil and maintaining it at a predetermined pressure higher than the pressure of the cooling gas, and the shaft. An air extraction tank that is provided in the return circuit from the seal part and stores the seal oil that returns from the shaft seal part by once releasing it to the atmosphere, an oil storage tank that collects the extracted seal oil from this air extraction tank, and this oil storage tank. In a sealing oil supply system for a rotating electric machine, the oil is sent to a cooler via an oil tank pump, cooled to a predetermined temperature, and then sent to the sealing oil tank again. A sealing oil supply device for a rotating electrical machine, characterized in that a bypass circuit is provided from the side to the air extraction tank via a tightening device and a bypass valve. (2) An automatic opening/closing valve is provided in the circuit connecting the upstream side of the differential pressure regulating valve and the air extraction tank, and the flow rate is to detect the amount of sealing oil supplied to the sealing oil supply pipe downstream of the differential pressure regulating valve. A sealing oil supply device port for a rotating electrical machine according to claim 1, characterized in that a relay is provided, and an automatic valve in the binox circuit is opened and closed by a detection signal corresponding to the flow rate of the flow rate relay.