JPH01316511A - Eccentricity monitor device for vertical shaft rotating motor - Google Patents

Abstract

PURPOSE:To prevent the trouble in contact of a stator and a rotor by providing at least more than three pieces of thermometers at the prescribed position of a guide bearing and providing a means for informing an abnormality when the temperature differences of these thermometers reach to a value higher than a prescribed value. CONSTITUTION:At least three thermometers, for instance, a thermometer elements 16 are provided at the prescribed position of a guide bearing 8. Then, there is provided a means for setting an abnormality when the temperature differences between these thermometers reach to a value higher than a prescribed value. In such a way, eccentric loads produced as the differences of the loads between the respective segment shoes 8a to 8d of the guide bearing 8 can be measured to prevent previously the trouble of contact of the stator 1 and rotor 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an eccentricity monitoring device for a vertical shaft rotating electric machine.

[Conventional technology]

As rotating electric machines have become larger in recent years, it has become important to ensure the reliability of operation, especially for indoor shaft turbine generators, and for this reason it has become important to install rotor eccentricity monitoring devices. There is.

Conventionally, rotor eccentricity monitoring devices have typically monitored the gap from the fixed side of the rotor. This is for detecting the gap in the radial direction with respect to the rotating shaft, as shown in, for example, ``Method for detecting partial contact of bearing device'' in Japanese Patent Application Laid-Open No. 55-2822.

A conventional example of a spindle generator will be explained with reference to FIG.

This example is an example of a so-called umbrella-shaped indoor shaft generator, and the stator (
A stator 1 is installed on concrete 2, and a rotor 3 is installed on the inner diameter side of the stator.

The rotor 3 has poles 4 facing the inner circumferential side of the stator 1, these balls 4 are attached to a yoke 5, this yoke 5 is attached to a spider 6, and the spider 6 is attached to a shaft (rotation axis). )7. The shaft 7 is engaged with the lower water wheel side through a coupling. This shaft 7 is supported by a guide bearing 8 that supports the horizontal direction and a thrust bearing 9 that supports the vertical load. The guide bearing 8 is divided into segment shoes, and these segment shoes are supported by a guide bearing support ring 1o via adjustment bolts 11. These guide bearing support ring 1o and thrust bearing 9 are attached to the end bracket 1.
2, and this end bracket 12 is further supported by the concrete 2. End bracket 12
A radial gap detection sensor 13a for monitoring the eccentricity of the shaft 7 and a radial gap detection sensor 13b are attached to the opposing portion. These sensors 13a, 13b are detected by transducers 14a, 14b, and eccentricity is measured.

A comparator 15 is attached to the transducer 14a, 14b, which outputs an alarm contact when the amount of eccentricity is exceeded, and operates as an eccentricity monitoring device.

Note that in the figure, 3a is a current collector.

[Problem to be solved by the invention]

In the prior art described above, where the stator 1 and the end bracket 12 are separately fixed as shown in FIG. 6, the stator 1 may be eccentric.

The mechanism of this eccentricity is that since the stator 1 is a part that generates electricity, a temperature rise occurs due to iron loss in the stator core and resistance loss in the coil. If the thermal expansion caused by this is restrained, excessive stress will be generated in the stator support part, leading to destruction, so the structure is usually such that it slides between the stator support part and the concrete support part.

Due to the ratchet effect caused by repeated thermal expansion and contraction, the stator l itself becomes eccentric. When this eccentricity occurs, as shown in FIG.
There is a difference in the air gap between the two, and no eccentric load is generated when not energized, but when energized, the magnetic attraction force between the stator 1° and the rotor 3 with the smaller air gap is large.
Since the magnetic attraction force on the side with a larger air gap is small, an eccentric load F is generated on the side with a smaller air gap. That is, since the rotation center C of the rotor 3 and the magnetic center M, which is approximately determined by the position of the stator 1, are slightly shifted, a force corresponding to the amount of eccentricity, that is, an eccentric load F is generated. By the way, since the above-mentioned gap detection sensor monitors only the eccentricity of the rotor, it hardly detects the eccentric load F in this case. For this reason, it was impossible to prevent troubles such as the expansion of the rotor due to thermal ratchet and contact between the stator 1 and the rotor 3, which was a problem.

The present invention has been made in view of the above points, and includes a stator 2.
It is an object of the present invention to provide an eccentricity monitoring device for a vertical shaft rotating electric machine, which makes it possible to prevent troubles due to rotor contact.

[Means to solve the problem]

The above purpose is achieved by providing at least three thermometers at predetermined positions of the guide bearing, and by providing means for detecting an abnormality when the temperature difference between these thermometers exceeds a predetermined value. achieved.

[Effect]

At least three thermometers are installed at predetermined positions on the guide bearing, and a means is provided to detect an abnormality when the temperature difference between these thermometers exceeds a predetermined value. It becomes possible to measure the eccentric load that appears as a difference in the loads of the segment shoes, and it becomes possible to detect the deviation of the magnetic center, making it possible to prevent problems of contact between the stator and the rotor.

That is, if the magnetic center deviates from the rotor center due to movement of the stator, an eccentric load is generated even though the center of one rotor hardly moves. This eccentric load appears as a difference in the load of each segment shoe of the guide bearing. Therefore, by attaching three or more thermometers to this guide bearing and measuring and comparing the temperatures, it is possible to detect the eccentric load caused by the deviation of the magnetic center, thereby making it possible to prevent accidents.

〔Example〕

The present invention will be explained below based on the illustrated embodiments. An embodiment of the invention is shown in FIGS. 1 and 2. FIG. Note that parts that are the same as those in the conventional system are given the same reference numerals, and therefore their explanations will be omitted. In this embodiment, at least three thermometers are provided at predetermined positions on the guide bearing 8, and a means is provided to detect an abnormality when the temperature difference between these ° thermometers exceeds a predetermined value.

By doing this, it becomes possible to measure the eccentric load that appears as a difference in the loads of the segment shoes 8a to 8d of the guide bearing 8, and prevents contact troubles between the stator 19 and the rotor 3. Thus, it is possible to obtain an eccentricity monitoring device for a vertical shaft rotating electric machine that enables the following.

That is, a thermometer, for example a resistance thermometer element 16, is embedded in the guide bearing 8. As shown in FIG. 2, out of the eight segment shoes of the guide bearing 8, four segment shoes 8a to 8
One resistance thermometer element 16 is embedded in each of the holes d. These are embedded at angular intervals of 90 degrees. The resistance thermometer elements 1'6a, 16b of the opposing segment shoes 8a, 8b are transducers 17a.

17b converts it into a voltage signal corresponding to the temperature, and the comparator 18a compares the absolute value of the temperature difference with a certain set value θ0, and when the set value θ0 or more is reached, the output signal is turned ON. Become. Resistance thermometer elements 16c and 16d, which are at an angle of 90 degrees with these resistance thermometer elements 16a and 16b, are similarly connected to transducer 17c,
The absolute value of the temperature difference is compared with a certain set value 00 by the comparator 18b through 17d, and the set value θ is determined. At the point above, the output signal is turned ON. These comparators 18a, 18. When either of the outputs b is turned on by the OR circuit 19a, an alarm contact is issued as the eccentric load is large.

By doing this, for example, the magnetic center of the stator 1 is aligned with the segment shoe 8a due to the thermal ratchet effect of the stator 1.
If it is eccentric in the direction, the air gap between the stator 1 and the rotor 3 in the eccentric direction of the inner circumference of the stator becomes large, so that an unbalanced magnetic attraction force acts in the direction of the segment shoe 8b. Therefore, the temperature of segment shoe 8b increases and the temperature of segment shoe 88 decreases. FIG. 3 is a graph showing this trend over time. In the figure, the horizontal axis represents time t, and the vertical axis represents the temperature difference θ(
This figure shows the change characteristics of temperature difference θ (Δθ) with time by taking ΔO). As shown in the figure, the tendency for the temperature Ob of the segment shoe 8b to rise and the temperature θ8 for the segment shoe 8a to fall increases as the eccentricity due to the ratchet effect progresses. The temperature difference θa Oh is 0
When (80) reaches a certain set value 0°, that is, at time t1, the comparator 18a turns ON, and the OR circuit 1
9a turns ON and outputs an alarm signal with a large eccentric load, making it possible to prevent further eccentricity. The set value (set temperature difference) Oo is the normal guide bearing 8
It is necessary that the variation in temperature is greater than 1 to 2°C, and is selected to be about 5 to 10°C. When an abnormality is detected by the monitoring device, the excitation and stator power are cut off, and the adjustment bolt 1 supporting the stator 1, end bracket 12, or guide bearing 8 is turned off depending on the degree of eccentric load.
1 and normal operation is possible again.

In this way, according to this embodiment, eccentric loads can be monitored by measuring the temperature difference between the segment shoes of the guide bearing, so that only the magnetic center of the stator etc. is eccentric.
Eccentricity can be monitored even when the rotor is not eccentric.

Another embodiment of the invention is shown in FIG.

In this embodiment, the resistance thermometer elements 16a and 1 of segment shoes 8a and 8b (see FIG. 2) of opposing guide bearings are constructed without attaching a transducer to each of the resistance thermometer elements.
6b is used as a bridge, and the difference is directly converted into voltage. A bridge is constructed with a fixed resistor 20 and a variable resistor 21, and the input voltage of the comparator 18d is initially adjusted to zero using the variable resistor 21. When a temperature difference occurs between the guide bearing segment shoes 8a and 8b, a resistance difference occurs between the resistance thermometer elements 16a and 16b, the bridge balance changes, and the voltage at the input of the comparator 18d changes. The value is compared with the voltage vO corresponding to the set value, and if it is higher than that value, it is turned ON. It is actually the segment shoe 8a of the guide bearing.

8b and segment shoe 8c in a 90 degree orientation.

Resistance thermometer elements 16c and 16d (both shown in FIG. 2) are attached to 8d, and processing of signals from comparator 18d onwards is the same as in the above case. In the same figure, 22
is a DC power supply. In this embodiment, the comparison transducer can be omitted in the case described above, and the number of wirings from the guide bearing to the monitoring device is only three, which is simple.

FIG. 5 shows yet another embodiment of the invention. In this embodiment, three resistance thermometer elements are installed, and comparators 18a, 18b, 18 are installed to check the temperature difference between them.
c is provided, and the absolute value of the temperature difference is compared with a certain set value, and if any one is greater than the set value, the OR circuit 19b outputs an alarm contact indicating an abnormality. In the figure, 17e, 17f, and 17g are transducers. According to this embodiment, the resistance thermometer element 16e.

The number of 16f and 16g can be reduced to three, which is smaller than in the above case.

As in the example above, any number of resistance thermometer elements may be installed as long as they are 3 or more, and instead of comparing pairs of resistance thermometer elements, they are used to create an average temperature, and the average temperature is measured. The same effect can be obtained by measuring the difference between the two and detecting an abnormality by turning it ON if the difference is greater than a certain value.

Further, in each of the above embodiments, only the absolute value of the temperature difference is detected, but the same effect can be obtained by detecting the trend of the temperature difference, that is, the rate of change over time.

〔Effect of the invention〕

As described above, the present invention is capable of preventing eccentricity of a vertical shaft rotating electric machine, which makes it possible to prevent problems of contact between one stator and two rotors, and thereby prevent problems of contact between two stators. Monitoring equipment can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional side view of a vertical shaft rotating electrical machine according to an embodiment of the eccentricity monitoring device for a vertical shaft rotating electrical machine of the present invention, FIG. 2 is an explanatory diagram showing the detailed configuration of the eccentricity monitoring device of FIG. 1, and FIG. Fig. 1 is a characteristic diagram of time and temperature difference showing the operating point of the eccentricity monitoring device, Fig. 4 is a circuit diagram showing the configuration of another embodiment of the eccentricity monitoring device for a vertical shaft rotating electrical machine of the present invention, and Fig. 5 6 is an explanatory diagram showing the detailed configuration of still another embodiment of the eccentricity monitoring device for a vertical shaft rotating electric machine of the present invention, FIG. 6 is a longitudinal cross-sectional side view of a vertical shaft rotating electric machine using a conventional eccentricity monitoring device for a vertical shaft rotating electric machine, and FIG. 7 is an explanatory diagram showing an eccentric load due to eccentricity between the stator and rotor in FIG. 6. FIG. 1... Stator, 3... Rotor, 8... Guide bearing, 88-8d... Segment shoe, 12...
・End bracket, 16 (16a-16g)...
Resistance thermometer element (thermometer), 17 (17a-17g)
...Transducer, 18 (18a to 18d)
... Comparator, 20 ... Fixed resistance, 21 ... Variable resistance, 22 ... DC power supply.

Claims (1)

[Claims] 1. Vertical axis rotation of a guide bearing that horizontally supports the rotor provided on the inner peripheral side of the stator, in which the end bracket that supports the guide bearing and the stator are not directly connected. In an eccentricity monitoring device for a vertical shaft rotating electric machine that monitors the eccentricity of an electric machine, at least three thermometers are provided at predetermined positions of the guide bearing, and the temperature difference between these thermometers is a predetermined value or more. An eccentricity monitoring device for a vertical shaft rotating electric machine, characterized in that it is provided with a means for detecting an abnormality due to the occurrence of an abnormality. 2. The means compares a temperature difference between a transducer that converts the temperature measured by the thermometer into a voltage signal corresponding to the temperature measured by the thermometer and each thermometer based on this voltage signal with a set value, and when the temperature difference exceeds the set value, An eccentricity monitoring device for a vertical shaft rotating electrical machine according to claim 1, which comprises a comparator that outputs an abnormal signal. 3. The means includes a series connection body in which two thermometers are connected as a pair, a series connection body of a fixed resistance and a variable resistance connected in parallel to this series connection body, and a connection between the thermometers of both series connection bodies. A DC power supply provided between the connecting part of the fixed resistor and the variable resistor, and the connecting part of both series connected bodies, and whose input voltage is compared with a predetermined value and is equal to or higher than the predetermined value. An eccentricity monitoring device for a vertical shaft rotating electric machine according to claim 1, which comprises a comparator that outputs an abnormal signal at a certain point in time. 4. Monitoring the eccentricity of a vertical shaft rotating electric machine in which the stator is not directly connected to the end bracket that supports the guide bearing of the guide bearing that is provided on the inner peripheral side of the stator and supports the rotor in the horizontal direction. In an eccentricity monitoring device for a vertical rotating electric machine, at least three thermometers are installed at predetermined positions of the guide bearing, and an abnormality is detected when the temperature difference between these thermometers exceeds a predetermined value. 1. An eccentricity monitoring device for a vertical shaft rotating electrical machine, which is characterized by having a means for monitoring eccentricity and turning off excitation and stator side power in the event of an abnormality.