JPS59153436A - Water cooler of winding for rotary electric machine - Google Patents

Abstract

PURPOSE:To improve the stable operation and the reliability by employing both an air ejector and a hydrogen concentration detector, thereby preventing hydrogen from staying in a coolant tank until it reaches dangerous concentration. CONSTITUTION:A drier 21 and a hydrogen gas concentration detector 22 are provided in series with an atmospheric air discharge tube 16, a pressure gauge 23 is provided at the end, an air ejector 26 is mounted through an air ejector air amount control valve 25 from a compressed air source 24 at the end in such a manner that the nozzle 27 is directed toward the inner gas discharging direction of a coolant tank 6, a gas flowmeter 28 is provided at the end, and the end is opened with the atmosphere. A discharging tube 16 is bypassed through a bypass tube 30 with a bypass flowrate control valve 29 around the nozzle 27 of the ejector 26. A hydrogen concentration meter 32 and an alarm unit 33 are provided in a rotary electric machine operation monitoring room 31, and an electric signal of a hydrogen gas concentration detector 22 is inputted via a signal line 34.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention cools an iron core directly with hydrogen gas, and cools the cooling water inside the winding conductor of a rotating electric machine. This invention relates to a water cooling system for rotating electric machine windings that can quickly detect leakage of water.

[Technical background of the invention and its problems]

Conventionally, as a cooling means for large-capacity rotating electric machines, the rotor and stator cores are heated to a high voltage (3 to 5
kgf/(me) Direct cooling is performed using high-purity (more than 98%) hydrogen gas, and the stator winding is directly cooled by making the conductor hollow and passing pure water (referred to as cooling water) through this hollow part. There was something that did cooling.

Recently, it has also become common to make the conductors of the rotor windings hollow and allow cooling water to flow through the hollow parts.

FIG. 1 and FIG. 2 show system diagrams of a conventional stator winding water cooling device for a rotating electric machine. Regarding the hydrogen gas sealed oil supply device, only the seal portion will be described and the rest will be omitted. In Figures 1 and 2, (1) is the stator winding, (2) is the stator core, (3) is the inlet pipe, (4) is the outlet pipe, (5)
is the pump, (6) is the cooling water tank, (7) is the cooler, (8)
is the temperature adjustment valve, (9) is the output adjustment foot', (10) is the filter, (11) is the ion exchange resin, θ is the insulated connection pipe, (1 is the outer frame of the rotating electric machine, 04) and the rotation (Iω is the in-flight cooling water pipe, (10 is the cooling water tank atmosphere discharge pipe, 07)
is the shaft seal part that seals hydrogen gas, (1 barrel is the hydrogen gas sealed oil supply inlet pipe, (IS) is the hydrogen gas sealed oil supply outlet pipe, and (IS) is the vent pipe.

This cooling device consists of a lower end of a cooling water tank (6) that stores cooling water, a pump (5) that transports the cooling water, and a cooler that cools the cooling water. valve(
8) and a filter 1110) that removes dirt from the cooling water.
and a pressure regulating valve (9) that adjusts the pressure of the cooling water are connected in series through the inlet pipe (3), and the stator winding (+) is connected via the in-machine pipe (15) and the insulated connection pipe (12+). Cooling water is led to one end.The other end of the stator winding (1) is connected to the delivery connection pipe (12).
and 'M' between the planes? (The outlet pipe (4) is connected to the lower end of the cooling water tank (6) via l to form a cooling water circulation circuit. Then, a portion of the cooling water flows from the point where it exits the filter (10). is returned to the cooling water tank (6) via an ion exchange resin θI) to improve the purity of the cold water. In addition, the outlet pipe (4) is connected to the upper part of the cooling water tank (6) by a ventilation pipe (a) at a position close to the in-flight pipe (1).In addition, the gas in the cooling water tank (6) is discharged to the atmosphere through a vent pipe (a). It is designed so that it can be released into the atmosphere at θ0.Also, the rotor 04) and stator core (2
) is sealed with high-purity hydrogen gas as a cooling medium for the rotary electric machine outer frame θ tank, and oil is supplied from a seal oil supply device (not shown) to the shaft seal portion 07 through the hydrogen gas seal oil supply inlet pipe (1 (to)). By doing so, it is isolated from the outside air. The oil supplied to the shaft seal portion 0'O is discharged from the hydrogen gas sealed oil supply outlet pipe.

During normal operation of the above-mentioned water cooling system, the pressure of the cooling water is approximately 2 kg (/cnl), and the hydrogen gas pressure is 3 to 5 kg.
kgf/ffl. In other words, the in-flight cooling water system (A:) consisting of the stator winding (1), the insulated connection pipe, and the in-flight cooling water piping (15+) is constantly under pressure of 1 to 3+ cgr/CIIt. If the in-flight cooling water system is damaged due to an abnormality, hydrogen gas will leak into the in-flight cooling system through the damaged area, pass through the outlet pipe (4), and enter the cooling water tank (6). Atmospheric discharge pipe ue
released into the atmosphere. Maintenance and operation of rotating electrical machines-1-1
Hydrogen gas consumption is constantly monitored, and if there is a significant increase, the cause will be investigated immediately. However, if the cause is within the in-flight cooling water system (A) and the damage is relatively minor, the leakage of hydrogen gas will be much faster than normal hydrogen gas consumption (about 10 m'/day). Therefore, by means of consumption monitoring, it is not possible to detect a failure until the damage progresses and the amount of hydrogen gas consumed clearly increases. The hydrogen gas that has entered the cooling water tank (6) is only released into the atmosphere by the action of one breath caused by a slight change in the water level in the cooling water tank (6), and is not sufficiently released. Therefore, even if the in-flight cooling water system (A) ruptures 111 and there is little hydrogen leakage or discharge, hydrogen gas will accumulate in the cooling water tank (6) and the water gas concentration will explode. Damage to the in-flight cooling water system must be detected early, as it is extremely dangerous for maintenance and operation as it is possible that the concentration could reach the limit concentration. This also applies to the rotor winding in-machine cooling system (not shown).

Therefore, a hydrogen gas concentration detector was attached to the atmosphere discharge pipe (O), and a fan was used to connect the atmosphere discharge pipe (161) to the cooling water tank (
6) Attempts were made to remove the internal gas and use a hydrogen gas concentration detector to detect hydrogen gas leaking into the cooling water. However, with this method, it is easy to cause excessive air flow.
As a result, it is difficult to detect hydrogen gas when its concentration is low, and skill is required to adjust the fan air volume to provide the appropriate amount of ventilation.
Improvements were requested.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a highly reliable water cooling system for rotating electric machine windings that can quickly and reliably detect hydrogen gas leakage into an in-machine cooling water system without requiring any skill.

[Summary of the invention]

In the present invention, the rotor and stator cores are directly cooled with hydrogen gas, and cooling water is circulated from a cooling water tank into the conductors of rotating electric machine windings such as rotor windings and stator windings. In a water cooling device for windings of a rotating electrical machine, the windings are directly cooled by IK, and the cooling water tank is provided with an atmosphere discharge pipe for discharging internal gas to the atmosphere.

By installing a hydrogen gas concentration detector in the atmosphere discharge pipe and an air ejector with a nozzle facing the internal gas discharge direction, the air ejector can eject a small but appropriate amount of air to the atmosphere without requiring any skill for cooling. The gas in the water tank is sucked and passed through a hydrogen gas concentration detector, and if there is a predetermined amount or more of hydrogen gas in the cooling water tank, the hydrogen gas concentration detector quickly and reliably detects it.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 3 and 4. In these drawings, the same parts as in FIGS. 1 and 2 are designated by the same reference numerals and their explanations will be omitted.

In this embodiment, the following devices are added to the conventional ffK shown in FIGS. 1 and 2. That is, a dryer Cυ and a hydrogen gas concentration detector (2) are installed in series in the atmosphere discharge pipe α0, and a pressure gauge (231
and a compressed air source c! 4) to the air ejector (2) via the air ejector air volume adjustment valve (2).
6) is installed with its nozzle (5) facing the direction of gas discharge inside the cooling water tank (6), and the waste flow-gauge (2al
and open the end to the atmosphere. Air ejector (
The discharge pipe (1e) is bypassed before and after the nozzle (5) of 26) by a bypass pipe (to) with a bypass flow rate adjustment valve.

A hydrogen concentration meter 32 and an alarm device (g) are installed in the rotating electric machine operation and monitoring room (31), and the electric signal of the hydrogen gas concentration detector 02 is inputted through the electric signal line 04.

Next, the effect will be explained.

If an abnormality occurs and the in-machine cooling water system is damaged during normal operation of the rotating electric machine, the hydrogen gas sealed in the outer frame θ9 of the rotating electric machine will leak into the in-machine cooling water system (5) and exit together with the cooling water. The pipe (4) enters the cooling water tank (6) through 8, separates from the cooling water, and emerges above the water surface. The air ejector (A) installed in the atmosphere discharge pipe 00 jets compressed air from the nozzle (27) in the direction of internal gas discharge while being regulated by the air volume adjustment valve (two).This jetted air causes the atmosphere discharge pipe ( The pressure inside L6) becomes negative pressure.This atmosphere discharge pipe αe
The pressure inside was provided in the bypass pipe (7)! ζIpass flow rate adjustment valve (To) and air ejector air volume adjustment valve (A)
The pressure is adjusted to 20-3 Q CTL AQ and monitored by a pressure gauge (GI). Thus atmospheric discharge pipe 06)
Due to the negative pressure inside the cooling water tank (6), hydrogen gas in the cooling water tank (6) is sucked into the atmosphere discharge pipe 0 () side, and the dryer (2
1), and when the hydrogen gas concentration detector (2) reaches a predetermined concentration or higher, it is quickly and reliably detected.
It is displayed on C3a, and also causes the W alarm device C()) to issue a peak alarm. In addition, the amount of hydrogen gas leaking due to damage to the in-flight cooling water system (A) can be determined by measuring the amount of air in the air ejector (iE
By knowing this under normal conditions, it is possible to detect the flow and increase in abnormal conditions3.Therefore, it is possible to quickly and reliably detect hydrogen gas leakage into the cabin/water system (A), even with immature bacteria, and to It is possible to know even the layer of hydrogen gas leakage, and it is possible to prevent high concentration hydrogen gas from accumulating in the cooling water tank (6).
Improvements in safe operation and reliability of rotating electric machines can be obtained.

It should be noted that the present invention is not limited to the embodiments described above and shown in the drawings, and may be applied, for example, to a stand for passing T♀ cooling water to a rotor winding (not shown). Of course, various modifications may be made without changing the gist of the invention.

〔Effect of the invention〕

As explained above, according to the present invention, by using an air ejector and a hydrogen gas concentration detector [7], a small amount of appropriate amount of air can be emitted into the atmosphere f[II+] without requiring any skill.
This allows hydrogen gas in the cooling water tank to be sucked in and to quickly and reliably detect when the hydrogen gas exceeds a predetermined amount, allowing immediate countermeasures to be taken against an accident and to prevent the hydrogen gas in the cooling water tank from reaching a dangerous concentration. It is possible to provide a water cooling device for windings of a rotating electrical machine that prevents water stagnation and improves safe operation and reliability.

[Brief explanation of drawings]

Figure R1 is a system diagram showing a conventional water cooling device for rotating electric machine windings, Figure 2 is an enlarged system diagram showing the main parts of Figure 1, and Figure 3 is a water cooling system for rotating electric machine windings according to the present invention. FIG. 4 is an enlarged system diagram showing the main parts of FIG. 3. 1 Stator winding 2 Stator core 6 Cooling water tank
14 Rotor 16 - Atmospheric discharge pipe 22 - Hydrogen gas concentration detector 25 Air ejector air amount adjustment valve 26 Air ejector 27 - Nozzle 29 Bypass flow rate adjustment valve 30...Pi/ξ pipe. Agent Patent Attorney Inoue - Male Figure 2

Claims (2)

[Claims] (1) The rotor and stator cores are directly cooled with hydrogen gas, and cooling water is circulated from a cooling water tank into the conductors of rotating electric machine windings such as rotor windings and stator windings to cool the windings. Direct Cooling 1~ In the water cooling device for rotating electric machine windings, the cooling water tank is provided with an atmospheric discharge pipe for discharging internal gas to the atmosphere, a hydrogen gas concentration detector is installed in the atmospheric discharge pipe, and the internal gas is discharged in a direction. 1. A water cooling device for rotating electric machine windings, characterized in that an air ejector is provided with a nozzle directed toward the windings of a rotating electrical machine. (2) A patent characterized in that the air ejector is provided with an air ejector air adjustment valve that controls the amount of compressed air released, and the air ejector air discharge pipes before and after the nozzle are provided with bypass pipes with valves that control the bypass flow. A water cooling device for rotating heavy machinery windings according to claim 1.