JPS6013245Y2 - Turbine generator temperature alarm device - Google Patents

Description

[Detailed description of the invention] This invention is a temperature alarm system for turbine generators, especially for turbine generators that require accurate detection of abnormal temperature distribution and abnormalities in the temperature detection sensor itself to generate alarms. This relates to alarm devices.

Conventionally, warning devices for such turbine generators include:
There was one with the configuration shown in Figure 1.

11 to 13 are sensors for detecting the temperature of the turbine generator;
For example, thermocouples are embedded in the stator of the generator.

The detection signals from these thermocouples 11 to 13 are amplified to a predetermined level by temperature converters 21 to 23 and then supplied to alarm setting devices 301 to 303 to set the set temperature T.

compared to

The alarm setting devices 301 to 303 are configured such that the temperature detection signal is the set temperature T.

, an alarm signal output is generated, and this alarm signal output is supplied to the OR circuit 44.

When the OR circuit 44 is supplied with the above-mentioned alarm signal output from any of the alarm setting devices 301 to 303, it operates and generates an output, and operates the alarm device 55 to generate an alarm.

This indicates that the temperature of the turbine generator has become higher than the set temperature.

However, according to this configuration, the maximum temperature is equal to the temperature set value T.
.

Even if an abnormal temperature distribution begins before the temperature exceeds T, the maximum temperature is T.

It is considered normal until it exceeds the temperature range, which causes undesirable thermal phenomena.

Moreover, the monitoring of the abnormal temperature distribution itself in that case is not in accordance with the operating conditions of the generator.

Furthermore, to detect abnormalities (for example, short circuits, open circuits) in the thermocouple itself, a separate detection circuit must be provided.

This invention was made to solve the above-mentioned drawbacks of the conventional technology. It detects abnormal temperature distribution properly at all times and in accordance with the operating conditions of the generator, and also uses the same detection circuit to detect thermoelectric power. It is an object of the present invention to provide a temperature warning device for a turbine generator that can detect abnormalities in the pair itself and issue an appropriate warning.

Hereinafter, one embodiment of this invention will be described in detail with reference to FIG. 2 of the drawings.

Thermocouples 11 to 13 serve as temperature detection sensors similar to conventional ones, and their detection signals are supplied to temperature converters 21 to 23 and amplified to a predetermined level signal, and then sent to the maximum value selection circuit 3 and the minimum value selection circuit 3. It is supplied to the value selection circuit 4.

The maximum value selection circuit 3 selects the maximum output of the amplified signals supplied from the temperature converters 21 to 23, and the minimum value selection circuit 4 selects the minimum output, and both outputs are sent to the subtracter 5. supply to.

In the subtracter 5, a signal of the difference between the maximum output and the minimum output, that is, the difference between the maximum temperature and the minimum temperature is formed, and this signal output is sent to the first comparison circuit 61 and the second comparison circuit 62. Supplied.

The first comparison circuit 61 converts the output signal of the subtracter 5 into
It is compared with a constant reference signal ΔT1, which is set in advance to be somewhat larger than the output signal of the subtractor 5 in a normal state, and if the output power supplied from the subtractor 5 is larger than the reference signal ΔT1, the output is determined. Occur.

On the other hand, the output current generated by the turbine generator is taken out by the current transformer (CT) 14 to the second comparison circuit 62.
The current converter 24 amplifies this signal to a signal of an appropriate magnitude, and the automatic reference signal setting device 10 automatically sets an automatic reference signal according to the output current state of the generator, that is, the operating state of the generator. A signal ΔT2 is input.

Note that this automatic reference signal ΔT2 is set to follow the output signal of the subtracter 5 slightly larger than the output signal in the normal state.

Therefore, in the second comparison circuit 62, the output signal from the subtracter 5 is compared with the automatic reference signal ΔT2, and the output signal from the subtracter 5 is compared with the automatic reference signal ΔT2.
An output is generated when the output signal of is greater than the reference signal ΔT2.

When the comparison circuits 61 and 62 generate outputs as described above, the alarm device 9 or 7, 8 is operated to generate an alarm indicating the occurrence of an abnormal temperature distribution or the occurrence of an abnormality in the thermocouple itself.

In addition, 9 in the figure is an alarm device for abnormal temperature distribution alarm, 7
8 indicates an alarm device for an open alarm of the thermocouple itself, and 8 indicates a short alarm alarm for the thermocouple itself.

Next, three types of operation patterns corresponding to each of these alarm devices will be explained.

(a) When an abnormal temperature distribution occurs in the stator of the turbine generator, a slight difference occurs between the output from the maximum value selection circuit 3 and the output from the minimum value selection circuit 4, resulting in a difference in the output from the subtractor 5. The signal becomes larger than the reference signal ΔT2, which is set to follow slightly larger than the difference signal in the normal state, in accordance with the operating condition of the generator.

As a result, the abnormal temperature distribution alarm device 9 issues an alarm.

(b) In the case of a short circuit in a thermocouple In this case, the output signal from the subtracter 5 becomes abnormally large and becomes larger than the reference signal ΔT1, which has been set to a somewhat larger constant value in advance. Comparison circuit 6
1 is output, and the short alarm warning device 8 warns of the abnormal state of the thermocouple.

[c] In the case of an open thermocouple In this case, a resistor with a large resistance value is connected between the power supply and one pole of each of the thermocouples 11 to 13 above, and this resistor causes the current to flow to each thermocouple to Configure the circuit to limit the current.

Then, if any thermocouple opens, one pole of the thermocouple will have a potential near the power supply voltage, and the output signal from the subtracter 5 will become larger.

When it becomes larger than the reference signal ΔT1, the first comparator circuit 61 outputs an output, and the open alarm warning device 7 issues a warning that the thermocouple is abnormal.

As seen in the above pattern, the reference signal ΔD□, which is set to be constant and somewhat larger than the difference output signal of the subtracter 5, is set to follow a value that is slightly larger than the difference output signal of the subtracter 5. By setting the reference signal ΔT2 (ΔTl>ΔT2) to an appropriate value, it is possible to generate separate alarms for an abnormality in the thermocouple itself and an abnormal temperature distribution.

However, in the above case, the reference signal ΔT is ΔT
Since the setting is larger than 2, the above pattern Cb),
When (c) occurs, that is, when the thermocouple itself is short-circuited or open, pattern [a] (abnormal temperature distribution alarm) will definitely occur.

As described above, according to this invention, in order to generate an alarm based on the difference between the maximum and minimum detected temperatures of the temperature detection sensor provided for the stator of the turbine generator,
No matter what temperature range the turbine generator is in, it can detect abnormalities in the temperature distribution and issue an alarm. This eliminates the drawback that no alarm is issued even if the device is awake.

Furthermore, the monitoring of abnormal temperature distribution in such cases is carried out in accordance with the operating conditions of the generator, and is comprehensively monitored throughout the entire process of generator operation to ensure that thermal problems do not occur. .

Therefore, the reliability and safety of the turbine generator can be significantly improved compared to conventional ones.

In addition, short-circuiting of the thermocouple itself, which was previously done separately,
Abnormalities such as open circuits can be detected simultaneously with abnormal temperature distribution detection using the same circuit, making it more economical in terms of space and cost.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a conventional temperature warning device for a turbine generator, and FIG. 2 is a block diagram showing the configuration of a temperature warning device for a turbine generator according to an embodiment of the present invention. 11-13...Thermocouple, 21-23...
・Temperature converter, 3...Maximum value selection circuit, 4...
... Minimum value selection circuit, 5 ... Subtractor, 61
...First comparison circuit, 62...Second comparison circuit, 7 to 9...Alarm device, 10...
...Automatic reference signal setter.

Claims (1)

[Scope of utility model registration request] A plurality of temperature detection sensors provided in the turbine generator, a maximum value selection circuit for extracting the maximum value output of the temperature detection signals supplied from these temperature detection sensors, and a maximum value selection circuit for extracting the maximum value output of the temperature detection signals supplied from the temperature detection sensors; A minimum value selection circuit that takes out the minimum value output, a subtraction circuit that obtains a signal of the difference between the maximum value output taken out by the maximum value selection circuit and the minimum value output taken out by the minimum value selection circuit, and this subtraction circuit. Compare the signal of the difference between the maximum value output and the minimum value output supplied by the reference signal with a reference signal set to be somewhat larger than the signal of the difference between the maximum value output and the minimum value output in a normal state, A first comparison circuit that generates an output when the output signal of the subtraction circuit is larger than the reference signal, and the maximum value output and the minimum value output in a normal state according to the state of the output current of the turbine generator. an automatic reference signal setter that automatically tracks and sets a reference signal that is slightly larger than the difference signal of a second comparison circuit that generates an output when the output signal of the subtraction circuit is larger than the reference signal set by the automatic reference signal setter, compared with the reference signal set by the reference signal setter; A temperature warning device for a turbine generator, comprising an alarm device that warns of an abnormal temperature distribution of the turbine generator or an abnormality of the temperature detection sensor based on the output of a first or second comparison circuit.