JPS5962796A - Enclosed oil feeder for rotary electric machine - Google Patents

Abstract

PURPOSE:To prevent temperature rise of enclosed oil under low speed operation, by varying delivery of sealing enclosed oil pump in accordance to rotation of rotary electric machine and controlling with correspondence to the amount required for the seal face of shaft thereby limiting the excessive delivery within predetermined range. CONSTITUTION:Rotation of a rotary electric machine 101 will increase/decrease while maintaining predetermined difference with rotation of a drive motor 122 for a sealing enclosed oil pump 120 in some range. Said pump 120 is volume type pump where the delivery will increase/decrease proportionally with rotation. Consequently the delivery of said pump 120 will decrease as the rotation of said machine 101 decreases thus to reduce enclosed oil amount to seal rings 104, 104. When the flow of enclosed oil to be fed to the seal face of the seal rings 104, 104 varies, delivery of said pump 120 is controlled to such flow as the excessive delivery is added to required recirculation, and even under low rotation of said machine 101 unnecessary abundant enclosed oil will never circulate between a degasifying enclosed oil tank 115 and said pump to prevent temperature rise of the enclosed oil.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an apparatus for supplying sealing oil to a shaft seal portion of a rotating electric machine, the interior of which is sealed with a cooling gas such as hydrogen gas.

[Ijl technical background of the invention]

A large rotating machine is configured to cool the inside by sealing a cooling gas, such as hydrogen gas, inside the machine. In such a rotary electric machine, a shaft seal portion is provided at the penetrating portion of the shaft to prevent internal hydrogen gas from leaking to the outside. Sealing oil is supplied to this shaft seal portion from a sealing oil supply device to cool the shaft 71 portion and maintain the sealing performance of this shaft seal portion.

Such a sealing oil supply device is constructed as shown in FIG. That is, 1 is a rotating electric machine, and hydrogen gas is sealed inside the rotating electric machine. Shaft seal parts 3, 3 are provided in the penetrating portion of the main shaft 2 of this rotating electric machine 1, and seal rings 4, 4 are provided in these shaft seal parts 3, 3. The seal oil supply device for supplying seal oil to the shaft seal parts 3, 3 is composed of a shaft seal part cooling system and a shaft seal part seal system.

The shaft seal cooling system is provided with a cooling seal oil tank 7, and the seal oil in the cooling seal oil tank 7 is supplied to the shaft seal part 3 through an oil cooler 29 by a cooling seal oil pump 8.
, 3 for cooling. And this shaft seal part 3,
The sealing oil that has flowed out of the outer pressure rings 4 and 3 is returned to the cooling sealing oil tank 7 via the air extraction tank 10. Further, the sealing oil flowing inside the seal ring 4.4 is configured to be returned to the cooling sealing oil tank 7 via the hydrogen gas separation tank 1o, the float trap tank 12, and the air extraction tank 1o.

Further, the shaft seal portion seal system μ is provided with a sealing oil tank 13 for deaeration.
The inside is evacuated to vacuum by a vacuum pump 14. And the oil cooler 2 of the shaft seal cooling system
A part of the sealing oil is taken out from the downstream of the sealing oil tank 9 and is sprayed into the sealing oil tank 13 for deaeration to remove dissolved moisture, air, etc. The sealing oil accumulated in the degassing sealing oil tank 13 is supplied to the sealing surfaces of the rings 4, 4 of the shaft seal parts 3, 3 by the sealing oil pump 15, thereby improving the sealing performance. configured to maintain. The seal oil supplied to the seal surfaces of the seal rings 4, 4 is sent to the cooling seal oil tank 7 together with the cooling seal oil, and the cooling seal oil tank 7 is used to seal the seals of the seal rings 4, 4. The same amount of sealing oil as that supplied to the surface is sent to the degassing sealing oil tank 13. By the way, the pressure of the sealing oil supplied to the sealing surface of the seal ring 4.4 needs to be maintained at a predetermined pressure, for example, 0.5 kg/crn2, higher than the hydrogen gas pressure within the rotating electric machine 1. . Further, the required flow rate of the sealing oil supplied to the sealing surfaces of the seal rings 4, 4 varies depending on the rotational speed of the main shaft 2 and the temperature of the sealing oil. For this reason, a differential pressure regulating valve 16 is provided on the discharge side of the sealing oil cylinder f1s. Therefore, this differential pressure regulating valve 16 is connected to a pressure guiding pipe 1.
The pressure of the sealing oil supplied to the seal surfaces of the seal rings 4, 4 and the pressure of the sealing oil discharged from the shaft seal parts 3, 3 are introduced through the seal rings 4, 17, and the differential pressure regulating valve 16 It is configured to adjust the flow rate of the sealing oil sent to the sealing surfaces of the sealing rings 4.4 in response to the differential pressure, and to control the pressure and flow rate of the sealing oil supplied to the sealing surfaces of the sealing rings 4.4. There is.

In addition, the above-mentioned sealing oil cylinder 7' i 5 is attached to the motor 1.
Since it is a positive displacement type driven by 8, is there a sealing oil for this seal? A pressure regulating valve 19 is provided between the valve 15 and the differential pressure regulating valve 16, and excess sealing oil of the sealing oil discharged from the sealing oil pump 15 is removed from the pressure regulating valve 19. The degassing oil is returned to the deaeration sealing oil tank 13, and the discharge pressure of the sealing oil pump 15 is maintained constant.

[Problems with background technology]

The flow rate of the sealing oil supplied to the sealing surfaces of the seal rings 4, 4 changes depending on the turning operation 94 operation change state and the rated operation state of the rotating electric machine. The discharge amount of the sealing oil pump 15 is set constant considering the necessary margin for the maximum required flow rate. Therefore, when the required flow rate is small, the surplus flow rate becomes extremely large. Then, this surplus flow rate is transferred to the sealing oil pump 1 for sealing.
5 and the deaeration seal oil tank 13, its temperature increases significantly due to the heat of agitation.For this reason, when the rotating electric machine 1 is rotating at a low speed, the deaeration seal oil The temperature of the sealing oil in the tank 13 rises excessively, and in order to prevent this, problems arise such as the total operating time of the sealing oil ponzo 15 must be limited. Particularly in large rotating electric machines, such as large turbine generators, the flow rate of sealing oil supplied to the 7-plane surface during turning operation is rated K i" + t, and the difference between 1/IU and -C
[Objective of the Invention] The present invention has been made based on the above circumstances, and its purpose is to provide a seal during low-speed operation of a rotating electric machine. An object of the present invention is to provide a sealing oil supply device for a rotating electrical machine that can prevent a rise in oil temperature. ? A shaft seal cooling system that circulates and cools the shaft seal; a deaeration seal oil tank that deaerates the seal oil taken out from the shaft seal cooling system; A sealing oil pump for supplying sealing oil to the sealing surface of the shaft sealing portion, an electric motor that rotationally drives the seven dongs, and a sealing oil pump provided on the discharge side of the sole sealing oil pump to the sealing surface of the shaft sealing portion. A differential pressure regulating valve that controls the flow rate of the sealing oil supplied to the sealing surface of the shaft sealing surface in response to the differential pressure between the pressure of the sealing oil supplied and the pressure of the sealing oil discharged from the shaft sealing part. , a pressure regulating valve that returns excess sealing oil from the sealing oil discharged from the sealing oil pump to the deaeration sealing oil tank, and a pressure regulating valve that detects the rotational speed of the rotating electric machine and responds to this rotational speed. A discharge amount controller (equipped with a back) that controls the rotational speed of the electric motor and controls the discharge amount of the sealing oil pump to be a predetermined amount higher than the flow rate. The discharge amount of the seal oil pump changes according to the rotation speed of the rotating electric machine, and is controlled according to the required amount to be supplied to the sealing surface of the shaft cooling part (a↓1, and the excess discharge amount is controlled by the operation of the rotating electric machine. Even if the situation changes, it is limited within a predetermined range, and therefore, even during low-speed operation, it is possible to prevent an excessive rise in the temperature of the sealing oil.

[Embodiments of the invention]

A first embodiment of the present invention will be described below with reference to FIGS. 2 to 4. In the figure, 101 is a rotating electrical machine such as a turbine generator, and a cooling gas such as hydrogen gas is sealed inside the machine.

Shaft seal portions 10 J and J 03 are provided in the penetrating portion of the main shaft 102 of this rotating electric machine 101.

This shaft knoll part J OJ, J O,? Seal rings 104, 104 are provided inside.

The sealing surfaces of the seal rings 104, 104 are connected to the main shaft 10.
2, and these knoll rings 10
4, 104 is divided in the circumferential direction in order to absorb vibrations of the main shaft 102 or to allow changes in the thickness of the oil film on the sealing surface, and is configured so that the inner diameter, that is, the diameter of the 7-hole, can be changed. has been done.

Seal oil is supplied to these shaft seal parts 103, 103 for cooling and maintaining sealing performance. Explain. Suna 4 Richi, this W
, f The sealing oil supply device is composed of a cooling system 105 for the shaft seat 21 and a seal system for the shaft seal.'11. ing.

The shaft seal cooling system 105 is constructed as follows. 1oy is a sealed Y tank for cooling, and sealing oil is stored inside this tank. The seal oil in this cooling seal oil tank 107 is stored in the cooling seal oil tank 10.
B, the oil is sent to the oil cooler 109, cooled to about 40° C., and then supplied into the shaft seal portions 103, 103 via the cooling sealing oil supply pipe 110 to cool the inside. ing.

Of the sealing oil supplied to these shaft seal parts 103, 103 for subsequent cooling, seal rings: to4, 10
The sealing oil flowing to the outside of 4 is sent to the air extraction tank 111,
After the mixed air is separated, the cooling seal oil tank 1θ
414 to be returned to 7. In addition, the lid sealing oil that has flowed inside the seal ring 104° 104 is sent to the hydrogen gas separation tank 112, and after the mixed hydrogen gas is separated, the float trazzo 4'l 1. It is configured such that it is sent to the air extraction tank 111 through the air extraction tank 111 and returned to the cooling sealing oil tank 107 from the air extraction tank 11. The float trap tank 113 is equipped with a float valve inside, and when a predetermined amount or more of hydrogen gas accumulates and the oil level of the internal sealing oil drops, the float valve closes to prevent hydrogen gas from flowing into the air extraction tank 111. It is for the purpose of

Further, the shaft seal portion seal system 1θ6 is constructed as follows. That is, 115 is a sealed oil tank for degassing, and the inside of this tank is constantly evacuated to odor by an odor pump 116.

And the oil cooler 1 of the shaft seal cooling system 1θ5
A part of the sealing oil is taken out from the downstream side of 09 through a take-out pipe 117, and is dispersed through a float nozzle 118 to a staghorn nozzle 119 and contained in a sealing oil tank 115 for deaeration. Moisture, air, etc. are completely removed and purified. Then, the sealing oil accumulated in the sealing oil tank 115 for deaeration (is supplied to the shaft seal portion through the oil supply pipe 12 by the sealing oil ponzo 120 for the 7-wheel). 3°103 no 7
- It is supplied to the sealing surfaces of the ring 104, 104, and is configured to separate the Vff sealing properties of the shaft sole portions 103, 103. And the seal ring 104,
The sealing oil supplied to the sealing surface of 104 is sent to the cooling @sealing tank 107 together with the cooling sealing oil.
The same amount of sealing oil as that supplied to the sealing surfaces of the seal rings 104, 104 is returned to the degassing sealing oil tank 115 through the take-out pipe 117 from the sealing oil tank 107 for degassing. It will be done. In addition, this sol ring 104,
The sealing oil supplied to the sealing surface of 104 is completely degassed in the degassing sealing oil tank 415 to remove moisture and air, so moisture, air, etc. are added to the hydrogen gas inside the rotating electrical machine Ioi. This prevents the contamination of hydrogen gas from causing a drop in cooling efficiency. Also,
The sealing oil tank 0120 is of a volumetric type such as a gas pump, and is driven by a driving electric motor 122 such as a three-phase fat conduction motor. Therefore, a differential pressure regulating valve 123 is provided on the discharge side of the sealing oil tank 120 for the vignette. This differential pressure regulating valve 123 is connected to a pressure guiding pipe 1.
24, 124 to the seal surfaces of the seal rings 104, 104 and the shaft seal portion 103.
The pressure of the stored oil discharged from the seal ring 103 is measured, and the differential pressure regulating valve 123 adjusts the flow rate of the seal oil sent to the seal surfaces of the seal rings 104, 104 in response to these differential pressures, and The pressure and flow rate of the sealing oil sent to the sealing surfaces 204 and 104 are maintained at predetermined values. Further, a pressure regulating valve 126 is provided between the seal equalizing oil bonzo 120 and the differential pressure regulating valve 123, and surplus sealing oil of the sealing oil discharged from the sealing oil bonzo 70J20 is removed. The pressure is sent from the pressure regulating valve 126 to the spray nozzle 127 for degassing & IJ oil tank 11.
The discharge pressure of the sealing oil tank 120 is maintained constant, and the sealing oil is recirculated to purify the sealing oil. It is structured in such a way that it is completely done.

In addition, this device is equipped with a discharge amount control mechanism, a U-type, which controls the discharge amount of the sealing oil bonnet 120 for the 7-hole.
The configuration will be explained below.

That is, 140 is a rotation meter generator provided at the shaft end of the rotating electric machine 101 or a rotation detector using a non-contact pulse signal, which generates an electromotive force and a pulse signal proportional to the rotational speed of the rotating electric machine 101. It is something. 141 is a detection signal converter that converts the detection signal of the rotation detector into a control signal corresponding to the rotation speed of the main shaft of the 11σ rotary electric machine 101; and 142 is an input control signal corresponding to the rotation speed of the turbine generator. A control output setting device 143 is used to select only a certain range and adjust it as an output signal, and 143 is an inverter for voltage 7-band wave number control installed in the power supply line of the driving motor 122 of the sealing oil cylinder f12°. This is a voltage control device.

The electromotive force or A pulse signal of the rotation detector 140 is
The detection signal is sent as a value that increases or decreases in proportion to the rotational speed of the rotating electric machine 1010 to the diaphragm 141, where a control signal ( Usually 1 to 5vnc)i converted.

For example, when the output signal of the signal converter 141 is IVDC, the rotating electric machine lθ1 must be stopped, and when it is 5VDC, it must be operating at the rated rotation.

The output signal of this signal converter 141 is converted into a control signal within a certain range (usually 4 to 20 mA DC or 1 to 5 V D) by proportional calculation operation in the control output setting device 142.
C range) and sent as an input signal to the voltage control device 143. Here, by changing the power frequency regime of the drive motor 122 in proportion to this control signal, the rotational speed of the drive motor 122 is sensed to increase or decrease.

Therefore, when the input signal of the control blade setting device 142, that is, the rotation speed of the rotating electric machine 101 is in a range of a certain value or more, the output signal of the control output setting device 142, that is, the rotation speed of the driving electric motor 122 of the sealing oil pump 120. It increases or decreases while maintaining a certain difference.

In this case, the relationship between the rotational speeds of the rotating electric machine 101 and the driving electric motor 122 is as shown in FIG. The seal oil pump 120 is a positive displacement type such as a gear pump.
Since it is 5 mm, the discharge amount increases or decreases in proportion to its rotational speed. Therefore, as the rotation speed of the drive motor 12.2 increases or decreases, the discharge amount of the sealing oil, tI477612θ, increases or decreases. Therefore, the sealing oil pump 1 for sealing
The discharge amount of 20 changes as shown by the solid line a-b-c-d in FIG. 4 as the rotational speed of the rotating electric machine 101 decreases. Also, -Transformer 10107-Ring, 104,1
04 decreases as shown by the dotted line in Figure 5, the sealing oil pump 1
The discharge amount of No. 20 is also decreased so that the difference in oil amount between them is maintained within a certain range.

Therefore, when the rotational speed of the rotation range 4 101 changes and the flow rate of the aX sealing oil supplied to the sealing surfaces of the seal rings 104, 104 changes, the sealing oil pump 120 for sealing changes accordingly. The discharge amount changes. Therefore, when the flow rate of the sealing oil supplied to the sealing surfaces of the seal rings 104, 104 changes, the discharge amount of the sealing oil pump 120 is adjusted to the surplus discharge amount corresponding to the recirculation flow rate required for the above flow rate. Controlled by flow rate! Sign. Therefore, the rotating electric machine 101
Even when the rotational speed is low, an unnecessarily large amount of seal oil does not circulate between the deaeration seal oil tank 115 and the 7-hole seal oil pump 120, and a rise in the temperature of the seal oil is prevented. Thread with things.

Note that the present invention is not limited to Example 1/1Iiii of 1. and 1.H.

For example, FIG. 2455 shows a second embodiment of the present invention. In this second implementation, the drive motor 122 is a secondary high-resistance type Sanwa squirrel cage induction motor, the speed detector 140 is a speed detection generator, and this detection signal is transmitted to the amplifier-i.
The primary winding voltage of the drive motor 122 is set via the reference voltage setter 150 and the reference voltage setter 150.

〔Effect of the invention〕

The present invention consists of a shaft seal cooling system that cools the shaft seal by circulating sealing oil through the shaft seal of a rotating electric machine in which cooling gas is sealed; and a shaft seal cooling system that cools the shaft seal. A deaeration seal oil tank that deaerates the taken out seal oil, a seal oil pump that supplies the seal oil in the deaeration seal oil tank to the sealing surface of the shaft seal portion, and this pump. A rotationally driven electric motor and a sealing oil provided on the discharge side of the sealing oil pump and supplied to the sealing surface of the shaft seal portion.

A differential pressure regulating valve that controls the flow rate of the sealing oil supplied to the sealing surface of the shaft sealing portion in response to the differential pressure between the pressure and the pressure of the sealing oil discharged from the shaft sealing portion, and a seal for the sealing portion. The excess sealing oil discharged from the oil pump is returned to the sealing oil tank for deaeration by a pressure regulating valve, and the rotational speed of the rotating electric machine is detected and the rotation of the electric motor is adjusted in accordance with this rotational speed. Speed control 111L A discharge amount control mechanism for controlling the discharge amount of the sealing oil pump to a discharge amount that is a predetermined number of needles higher than the flow rate. Therefore, the discharge amount of the sealing oil pump for sealing changes in accordance with the rotational speed of the rotating electric machine, and is controlled in accordance with the necessary amount supplied to the sealing surface of the shaft seal part, and the excess discharge amount is used to operate the rotating electric machine. Even if the state changes, it is limited within the range of Fjr constant, and therefore, even during low-speed operation, it is possible to prevent an excessive temperature rise of the sealing oil, etc., and the effect is great.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a conventional example. Figures 2 to 4
The figure shows a first embodiment of the invention, FIG. 2 is a schematic configuration diagram,
FIG. 3 is a diagram showing changes in the rotational speeds of the rotating electric machine and the drive motor, and FIG. 4 is a diagram showing changes in the flow rate of sealing oil. In addition, Fig. 5 shows 101...Rotating electric machine, 1o3...Shaft seal part, 104...Seal ring, 1o5...Shaft seal cooling system, 1.05...Shaft 7-Roll part seal system, 107.・・・
Cooling sealing oil tank, 116...Non-sealing oil tank for deaeration, 120...Sealing oil pump, 122...Drive motor, 123...Differential pressure regulating valve, 126...Pressure adjustment Firefly valve, IJO...discharge rate control mechanism. Applicant's agent Patent attorney Takehiko Suzue Figure 1 Figure 2 21 Figure 3 Figure 5 21

Claims (1)

[Claims] A shaft seal cooling system that cools the shaft seal by circulating seal oil through the shaft seal of a rotating electric machine, which has cooling gas sealed inside, and a seal taken out from the shaft seal cooling system. Drives a deaeration seal oil tank that deaerates oil, a seal oil pump that supplies the seal oil in this deaeration seal oil tank to the seal surface of the shaft seal part, and this seal oil pump. The pressure difference between the pressure of the sealing oil that is provided on the discharge side of the sealing oil pump and the sealing oil that is supplied to the 7-face of the shaft sealing part and the pressure of the sealing oil that is discharged from this shaft sealing part. A differential pressure regulating valve that controls the flow rate of sealing oil supplied to the sealing surface of the shaft seal portion in response to the A pressure regulating valve that returns the oil to the sealing oil tank detects the rotational speed of the rotating electric machine, controls the rotational speed of the electric motor in accordance with this rotational speed, and adjusts the discharge amount of the sealing oil pump based on the flow rate. A sealing oil supply device for a rotating electric machine, characterized by being equipped with a discharge amount control mechanism that controls the discharge air to be increased by a fixed amount.