JP2900695B2 - OF cable oil leak alarm generation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates monitors the oil level of the oil supply tank for OF cables, relates to oil leakage alarm how the OF cable for detecting oil leakage OF cables, in particular, with a simple structure relates to oil leakage alarm how the oF cable can be detected in and a small amount of oil leakage regardless of the seasonal variation and transmission conditions change.

[0002]

2. Description of the Related Art A fuel tank is connected to an OF cable, and
Upon refueling the F cable hand, the oil due to damage or the like of the OF cables sometimes accidents leaking out occurs.
As a means for discovering this, an oil leak alarm generator is used.

Conventionally, an oil leak alarm generating device is provided in a fuel tank as shown in FIG. 2, and monitors an oil level in the oil tank so that an alarm is issued when the oil level drops abnormally. It is configured. That is, the fuel tank 3 shown in FIG.
At 0, 31 is a tank tank body, 32 is an oil level gauge provided in a vertical direction along the tank tank body, 33 is a float that moves up and down in the oil level gauge according to oil level rise and fall, and 34 is Proximity sensors for detecting the float, 35 are cells provided in multiple stages, and 36 is an oil passage communicating with the OF cable. In the figure, A, B, and C indicate oil level positions, respectively.

[0004] The oil level A indicates the oil level in a certain power transmission state. When the float descends due to a decrease in oil due to oil leakage or the like, the proximity sensor is located at the height of the oil level C. Therefore, when the oil level falls to the oil level C, the proximity sensor detects this and detects the oil leakage. An alarm can be generated and transmitted to a monitoring device or the like.

[0005] Here, the oil level B is an oil level when there is no load in winter. As illustrated, the oil level C is set slightly below the oil level B. This is because the oil level in the refueling tank fluctuates according to the season, and the oil level is high in summer and low in winter.
Also, since the calorific value differs depending on the magnitude of the load on the OF cable, the oil level increases as the load increases, and the oil level is lowest when there is no load in winter. That is, since the oil level C for generating an alarm is below the oil level B when there is no load in winter, no alarm is erroneously generated when there is no load in winter. Also, if there is an oil leak at the time of no load in winter, the proximity sensor works immediately and an alarm is generated.

On the other hand, during the power transmission operation in the summer, the oil level rises greatly, and the head between the oil level A and the oil level C increases. In such a case, if an oil leak occurs, a large amount of the oil leak is left before the proximity sensor operates, and an alarm is finally generated when the oil level drops to the oil level C.

As a solution to such a problem, there is a method of adjusting the height of a float type switch for detecting oil leakage according to the season. That is, the float switch is fixed at a low position in winter and at a high position in summer. Thus, since the float switch is located at a high position in summer, an alarm can be generated before a large amount of oil leaks.

Further, the oil amount in a normal case can be calculated and estimated based on the temperature of the OF cable, the temperature of the oil supply tank, and the like. There is also a method of utilizing this to detect an oil leak by comparing the estimated oil amount with the actually measured oil amount.

[0009]

However, in the method of adjusting the height of the float switch according to the season, it is necessary to adjust the position of the float switch each time according to the season.
Also, the adjustment amount can be determined by a stopper or the like between the highest position and the lowest position, but adjustment is troublesome at an intermediate position. In addition, when there is a temperature change due to the climate, it cannot cope.

On the other hand, in the method of detecting the oil leak by comparing the estimated oil amount with the actually measured oil amount, it must be possible to measure the oil level regardless of the position of the oil level, so that it can be continuously measured over a wide range. A sensor must be installed, and the configuration is complicated.

[0011] Therefore, an object of the present invention is to solve the above problems, a simple configuration, the oil leakage alarm how the OF cable can be detected in and a small amount of oil leakage regardless of the seasonal variation and transmission conditions change To provide.

[0012]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention calculates an ideal operating oil level of an oil tank from the temperature of an OF cable during operation and the temperature of an oil tank. Alternatively, the lower limit oil level alarm sensor is moved to an oil level position where a certain amount of oil is reduced, and an oil leak alarm is generated when the actual oil level is detected by the lower oil level alarm sensor. .

[0013]

According to the above configuration, the ideal operating oil level provides an oil level when the OF cable is operating normally without oil leakage. Since the lower limit oil level alarm sensor is at the same or slightly lower position than the ideal operating oil level, even if a small amount of oil leaks, the oil level is detected by the lower limit oil level alarm sensor, and an alarm is generated.

The temperature change due to the season, the climate or the like raises and lowers the oil level, but the ideal operating oil level can be changed corresponding to this elevation since it is based on temperature measurement. Therefore,
The lower limit oil level alarm sensor also changes in response to the elevation, and the difference from the ideal operating oil level is kept constant.

Further, the lower limit oil level alarm sensor can be realized with a simple configuration that only detects the presence or absence of an oil level.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

First, the principle of calculating the ideal operating oil level of the oil tank from the temperature of the OF cable and the temperature of the oil tank will be described.

The oil level that should be in the oil tank at a certain point in time is
That is, the ideal operating oil level is determined by the OF cable and oil tank temperature at that time if the cable type, span length, oil tank type and capacity of the track are determined. The method for obtaining the value is described in, for example, Design of Electric Cable Industry Association No. 387 OF Cable Refueling Design (1983).

That is, the amount of oil change in the system in the case of the next line and oil tank is calculated based on Table 1. Here, the line is 275 kVOFAZV 1 × 1000 mm ² , the length is 1 km, the ends are CH and SJ, and two pairs of intermediate connections.
The refueling tank is an OPT (integral type) 15 cells.

[0020]

[Table 1]

The changing oil amount is obtained by a relational expression of changing oil amount = unit changing oil amount × quantity × oil expansion coefficient × temperature change.

As shown in Table 1, if the temperature of CH and the temperature of each connection portion can be obtained, a strict change oil amount can be obtained. However, since most of the oil amount is the OF cable and the oil supply tank,
It can be considered that these two temperature changes mainly relate to the entire changed oil amount.

Since the amount of change oil is easily calculated in this way, it can be obtained by a simple arithmetic circuit by measuring and inputting the temperature of each part, especially the temperature of the OF cable and the oil supply tank. Further, since the change in the oil amount is proportional to the change in the oil level of the oil supply tank, the oil level can be easily obtained by an arithmetic circuit or the like.

A method for generating an oil leak alarm of an OF cable according to the present invention will be described with reference to an apparatus 1 shown in FIG. The refueling tank tank body 31, the oil level gauge 32, and the float 33 are the same as those described in the conventional example of FIG.
Is formed in a tubular shape closed at the top and bottom to accommodate oil, and an oil level gauge 32 formed in a tubular shape outside and communicated with the oil supply tank tank body 31 is arranged vertically along the oil supply tank tank body 31. Direction. In the oil level gauge 32, a float 33 that moves up and down in the oil level gauge according to the oil level is stored.

A rotary shaft 2 and a fixed shaft 3 extending vertically along the oil level gauge are provided in parallel. A servo motor 4 is provided below the rotating shaft 2.
The rotation shaft of the servomotor 4 is connected to the rotation shaft 2. The rotating shaft 2 is threaded, while
The fixed shaft 3 is constituted by a round bar. The rotating shaft 2 and the fixed shaft 3 are supported by a refueling tank body 31 via a mount 5. A warning surface moving base 6 is attached to the rotating shaft 2 and the fixed shaft 3.
The alarm surface moving base 6 has a female screw hole and a slide bearing hole, and the rotary shaft 2 is screwed and inserted into the female screw hole,
The fixed shaft 3 is inserted through the slide bearing hole.
When the rotating shaft 2 rotates, the alarm surface moving base 6 is configured to be able to move up and down. In addition, fixed shaft 3
Prevents rotation of the warning surface moving base 6 at that time.

A proximity sensor 7 is attached to the alarm surface moving base 6. The proximity sensor 7 is provided facing the oil level gauge 32, and has a configuration in which the proximity sensor 7 moves up and down along the oil level gauge 32 when the alarm surface moving base 6 moves up and down. The proximity sensor 7 detects the float 33 and detects the presence or absence of an oil level. When the float 33 is within a predetermined distance, for example, it can generate an ON signal. The proximity sensor 7 attached to the alarm surface moving base 6 constitutes a lower limit oil level alarm sensor 8 for detecting when the float 33 moves up and down the oil level gauge 32 and reaches the same height position. . The output of the lower limit oil level alarm sensor 8 is connected to a control unit 9 including an arithmetic circuit, a computer, and the like. The control unit 9 has a function of generating an oil leak alarm in accordance with the output of the lower-limit oil level alarm sensor 8 and notifying the alarm to a remote monitoring device, a display panel, and the like.

Although not shown, an oil tank temperature sensor for measuring the temperature of oil contained in the oil tank 30;
OF for measuring the temperature of oil contained in an OF cable
A cable temperature sensor is provided, and outputs 10 and 11 of these temperature sensors are both connected to the control unit 9. The control unit 9 can obtain the changed oil amount from the temperature of the OF cable and the temperature of the oil supply tank based on the above-described formula for calculating the changed oil amount. Then, the control unit 9 calculates the oil level of the oil supply tank 30 proportional to the change oil amount, and sets the oil level as an ideal operation oil level, and sets the ideal operation oil level or the oil level at which a certain amount of oil is reduced from the ideal operation oil level. The surface alarm sensor 8 can be moved.

Next, the operation of the embodiment will be described.

When an OF cable provided with the oil leak alarm generating device 1 shown in FIG .
The temperature of the F cable and oil tank rises. The temperatures of the OF cable and the fuel tank change depending on the season and the weather. These temperatures are measured by an oil tank temperature sensor and an OF cable temperature sensor. Control unit 9
Calculates the ideal operating oil level S that should be in normal operation from these temperatures. Now, assuming that the OF cable is under normal operation without oil leakage or the like, the actual oil level matches the ideal operation oil level S.

Further, the control unit 9 sets the ideal operating oil level S-α
Is the lower limit oil level S _MIN, and the servo motor 4 is driven to move the lower limit oil level alarm sensor 8 to the position of the lower limit oil level S _MIN . The rotation of the servomotor 4 is transmitted to the rotating shaft 2, and the alarm surface moving base 6 moves up and down with the rotation of the rotating shaft 2. Here, α is 0 or a small value appropriately determined in consideration of an error, a margin, and the like. Therefore, the lower limit oil level alarm sensor 8 is configured to output the ideal operating oil level S or the level immediately below the ideal operating oil level S
It will be moved to the lower limit oil level S _MIN . At this time, the ideal operating oil level S fluctuates based on the temperature of the OF cable and the oil supply tank, but the lower limit oil level S _MIN moves to follow this, and is always at a position where α has been reduced.

When oil leaks due to damage to the OF cable, the actual oil level in the oil supply tank 30 drops because the total oil amount decreases. At this time, the float 33 in the oil level gauge 32 also descends, and immediately reaches the lower limit oil level S _MIN . When the actual oil level reaches the lower oil level S _MIN , the lower oil level alarm sensor 8 detects the float 33 and outputs an ON signal indicating an alarm to the controller 9. In response to this, the control unit 9 generates an oil leak alarm and notifies the remote monitoring device, the display panel, and the like.

In this embodiment, the OF cable temperature sensor and the oil tank temperature sensor are provided to calculate the ideal operating oil level S of the oil tank. The ambient temperature of a cableway, a pipe, or the like in the cable may be measured, and the measured temperature may be used as the OF cable temperature or the oil tank temperature. In this configuration, the calculation of the ideal operating oil level S is not strict, but it is sufficient when strictness is not required. By shifting the position, a margin can be provided before an alarm is generated.

The oil leak alarm generator 1 according to the present invention includes:
A conventional fixed lower limit oil level alarm sensor based on the oil level at the time of no load in winter may be used in combination.

The control unit 9 includes a lower limit oil level alarm sensor 8
In addition to generating an oil leak alarm based on the OF cable temperature sensor, the OF cable temperature sensor may also monitor the OF cable temperature to detect an abnormal OF cable temperature.

[0035]

The present invention exhibits the following excellent effects.

(1) Since a lower limit can be set immediately below a normal oil level, an oil leak alarm can be generated with a small amount of oil leak.

(2) Since the oil leakage can be detected at a constant amount without being influenced by seasonal fluctuations or power transmission status changes, it is possible to warn early of an oil leakage even during the power transmission operation in summer.

(3) Since it is sufficient to provide a temperature sensor and a sensor for detecting the presence or absence of an oil level, the configuration of the oil leak alarm generating device is simple.

[Brief description of the drawings]

FIG. 1 is a schematic view of an oil leak alarm generating device for explaining an embodiment of the present invention.

FIG. 2 is a schematic view of an oil supply tank connected to an OF cable and a conventional oil leak alarm generating device.

[Explanation of symbols]

1 Oil leak alarm generator 8 Lower limit oil level sensor S Ideal operating oil level S _MIN lower limit oil level

Claims (1)

(57) [Claims] An oil supply tank is connected to an OF cable.
Hand upon refueling within the cable, to calculate the ideal operating oil level of the oil supply tank and a temperature of the oil supply tank of OF cable in operation, the oil level position obtained by subtracting a certain amount of oil than the ideal operating oil level or which moving the lower oil level alarm sensor, when the actual oil level is detected by the lower limit oil level alarm sensors, oil leakage alarm how the oF cable, characterized in that so as to generate an oil leak alarm.