CN201771603U - Temperature collecting device of mini-type gas turbine - Google Patents

Abstract

The utility model discloses a temperature collecting device of a mini-type gas turbine, which is arranged in a gas turbine control system of the mini-type gas turbine. The temperature collecting device of the mini-type gas turbine comprises a thermocouple, an integrated temperature sensor AD590 and a signal collecting device, wherein the thermocouple is arranged at air discharge end of a turbine of the gas turbine, and used for measuring the temperature of gas discharged by the turbine of the gas turbine, and converting the temperature into electrical signals; the integrated temperature sensor AD590 is connected in series with the cold end of the thermocouple; and the signal collecting device is connected with the other end of the thermocouple, and used for receiving the electrical signals converted by the thermocouple. The temperature collecting device can indirectly measure the gas inlet temperature of the turbine by measuring the gas discharge temperature of the turbine, and has the advantages of simple structure, convenient measurement and high measuring precision.

Description

The temperature collecting device of miniature gas turbine

Technical field

The utility model relates to temperature collecting device, especially the temperature collecting device of miniature gas turbine.

Background technique

The research of domestic micro fuel engine power generation and control technique is at the early-stage, is in the stage that introduction of foreign technology absorbs and develops on the current overall context.Aspect micro fuel engine power generation unit and power converter control system, comparatively advanced and complete micro fuel engine power supply system have been arranged abroad.Representative is the precious Man of Britain, the Capstone of the U.S. and Honeywell Inc., and its product electric motor power concentrates between 25kW～80kW, and the micro fuel engine of 200kW～300kW each company at present all is in the development phase.By investigation and analysis to market, the inventor thinks: have a large population owing to China on the one hand, electricity needs is big, the process heat demand is big, civil heating and life increase sharply with heat, on the other hand, because energy shortage is to an urgent demand of energy-conservation proposition, and the development need of the little heat in rural area, electricity, make the micro fuel engine power generation system have very wide market application prospect.

The micro fuel engine power generation unit mainly is made up of gas compressor, turbine, firing chamber, regenerator, pneumatic bearing, generator, power converter, fuel injection system etc.The whole system operation process is as follows: the air of cleaning through the gas compressor supercharging after, enter regenerator, after the tail gas of discharging with turbine carries out heat exchange, send into the firing chamber, with the fuel mix burning of nozzle ejection, and promote the turbine acting, drive generator for electricity generation.The electric energy that generator sends, after the power converter conversion, the Ac of customer requirements is satisfied in output.In turbine Control merit frequency regulon, the variable of major control has:

Combustion machine rotation speed n;

Fuel flow rate q _Mf

Turbine inlet fuel gas temperature

Regenerator regenerator effectiveness R;

Fuel pressure p before the fuel valve inlet;

Compressor delivery pressure p ₂

Central unit is the control core of above-mentioned micro generation unit control system, finish the overall coordination control and the tasks such as real-time data acquisition, fault diagnosis and warning of whole micro fuel engine system, mainly form by starting control module, control load module, control output module, data acquisition module, system mode diagnosis and alarm module.

Particularly important with processing in the central unit to selection of temperature signal.The turbine intake temperature is very important controlled quentity controlled variable in the turbine control system.But because intake temperature is very high, measuring cell is easy to be burnt, and the temperature field also is easy to inhomogeneous, and therefore, actual being difficult to of thermometry carried out.

Summary of the invention

The purpose of this utility model provides a kind of temperature collecting device of miniature gas turbine, and it can record the turbine intake temperature of miniature gas turbine by the method for indirect measurement, and this apparatus structure is simple, the measuring accuracy height.

Technical conceive of the present utility model is as follows: according to the gas temperature of miniature gas turbine turbine discharge

With the turbine intake temperature

In the online the most similar characteristic of trend of characteristic curve, revise by replenishing other factors, to reach right

Indirect measurement.

According to above-mentioned technical conceive, for achieving the above object, the utility model provides a kind of temperature collecting device of miniature gas turbine, is located in the turbine control system of miniature gas turbine, and the temperature collecting device of described miniature gas turbine comprises:

One thermocouple is located at the turbine exhaust end of described miniature gas turbine, and the turbine of measuring described miniature gas turbine is in real time discharged the temperature of gas, and is electrical signal with temperature transition;

One integrated temperature sensor AD590 is connected in series with the cold junction of described thermocouple;

One signal pickup assembly is connected with the other end of described thermocouple, receives the electrical signal that thermocouple changes.

Because the gas temperature that the turbine of miniature gas turbine is discharged

With the turbine intake temperature

The most similar in the trend that characteristic curve is online, and

It is reflection

The characteristic of principal element, therefore revise to reach right by replenishing other factors

Monitoring and control.

According to the turbine intake temperature

With the gas temperature of discharging

And turbine is imported and exported gas and is calmed the anger and compare π _TRelation:

$T_2^{*}=T_1^{*}[1-(1-\frac{1}{{\mathrm{\π}}_T^{m_g}}){\mathrm{\η}}_T]$

Can get $T_1^{*}=\frac{T_2^{*}}{1-{\mathrm{\η}}_T+\frac{1}{{\mathrm{\π}}_{\text{T}}^{m_g}}{\mathrm{\η}}_T}$

In the formula

(k _g=1.33---ratio of specific heat); η _TBe efficiency of heat engine.

At π _TChange when very little, by changing

Maintenance is revised in the variation of value

Constant, promptly

Set up With Δ π _TBetween the relation:

$\frac{\mathrm{\Δ}{T}_2^{*}}{\mathrm{\Δ}{\mathrm{\π}}_T}=-\left(\frac{\∂T_1^{*}}{\∂{\mathrm{\π}}_T}\right)/\left(\frac{\∂T_1}{\∂T_2^{*}}\right)$

Following formula is keeping

Under the permanence condition,

With Δ π _TThe curve that changes be exactly after the linearization etc.

Line.As can be seen with

Measure indirectly

The time, use π _TMethod for correcting reaches temperature

Control.

According to above-mentioned principle, the inventor has designed temperature collecting device described in the utility model.Wherein thermocouple measurement is exactly the gas temperature that turbine is discharged Because thermocouple is the difference temperature measurement device, when handling thermocouple signal, hold as reference with cold junction point, consider the voltage of non-zero degrees celsius cold junction point, must carry out the compensation of cold junction point to the thermocouple output voltage.The inventor utilizes the linear temperature-sensing property of integrated temperature sensor AD590, and it is connected with the cold junction of thermocouple, for the cold junction of thermocouple provides temperature correction, makes the cold junction of thermocouple all produce the voltage of 0V under any ambient temperature.

Preferably, the temperature collecting device of described miniature gas turbine also comprises: a biasing resistor is connected in series with described integrated temperature sensor AD590.

When thermocouple is in 0 ℃ of environment, its cold junction need not compensate, but integrated temperature sensor AD590 still has the electric current output of 273.2 μ A in the time of 0 ℃, in order to improve thermometric precision, need integrated temperature sensor AD590 not produce offset voltage at the cold junction of thermocouple, therefore be provided with biasing resistor, when applying a voltage, just on biasing resistor, formed a bias voltage.

Preferably, described thermocouple is a K type thermocouple.

Preferably, the temperature collecting device of described miniature gas turbine also comprises: a wave converter, and it is connected with described signal pickup assembly, and the electrical signal that signal pickup assembly is received carries out wavelet transformation.

Preferably, the temperature collecting device of described miniature gas turbine also comprises: a wave filter, it is connected with described wave converter, is used to filter the HFS of electrical signal, obtains even more ideal temperature signal.

The utility model is owing to adopted above technological scheme, make that this apparatus structure is simple, measuring accuracy is but very high, and wherein integrated temperature sensor AD590 is kelvin temperature-current sensor, it can directly become temperature transition corresponding output current, and has standardization (the linearity output of 1 μ/K); In addition, because integrated temperature sensor AD590 output is electric current, with long line transmission signal the time, can not produce error because of the noise voltage of voltage drop or induction, it is also very strong to suppress interference capability, so can be used for longer-distance thermometry; Moreover integrated temperature sensor AD590 is equivalent to the current source of a HR high resistance (10M Ω), energizing voltage is changed insensitive, and it is low in energy consumption simultaneously, 13mW only when maximum.

Description of drawings

The utility model is described in further detail below in conjunction with the drawings and specific embodiments.

Fig. 1 is the design principle figure of temperature collecting device described in the utility model.

Fig. 2 concerns schematic representation for thermocouple being provided with in the miniature gas turbine control system in the temperature collecting device described in the utility model.

Fig. 3 is the circuit connecting relation schematic representation of integrated temperature sensor AD590 in the temperature collecting device described in the utility model.

Embodiment

As shown in Figure 1, the gas temperature of miniature gas turbine turbine discharge

With the turbine intake temperature

The most similar in the trend that characteristic curve is online.

As shown in Figure 2, gas K enters burning in the firing chamber 1 of miniature gas turbine with fuel P after by the compression of gas compressor 6, and the gas of generation enters turbine 2 backs and discharges this process output work L.The gas of discharging enters regenerator 4 behind throttle valve 3, K type thermocouple 5 is located at and is measured the temperature that turbine 2 is discharged gas in the regenerator 4.

K type thermocouple cold junction and AD590 are connected in series circuit diagram as shown in Figure 3.U among the figure _rExpression measuring end voltage, U _kThe cold junction voltage of expression K type thermocouple, I _kBe the output current of AD590, U _cBe resistance R _cOn pressure drop, also be offset voltage, V _RefBe reference voltage, reference voltage V in the present embodiment _RefBe 2.5V.AD590 can experience the ambient temperature of the cold junction of K type thermocouple in this temperature collecting device, and electric current I affords redress in 0 ℃～50 ℃ scopes _k, so just in resistance R _cLast formation offset voltage U _c, as to voltage U _kCompensation.When ambient temperature is 0 ℃, do not need to carry out voltage compensation, but AD590 this moment still provides the offset current I of 273.2 μ A _k, in order to prevent in resistance R _cLast formation offset voltage U _c, the reference potential of using low pressure fiducial chip MC1403 output 2.5V this moment just can form bias voltage as reference voltage on biasing resistor R.

Like this, the cold junction of integrated temperature sensor AD590 and K type thermocouple polyphone, thus temperature correction is provided for the cold junction of K type thermocouple, make the cold junction of K type thermocouple under any ambient temperature, only produce the 0V electromotive force.And the other end of K type thermocouple just can become detected temperature into temperature signal the voltage signal of 0～3.3V through the thermocouple transmission circuit, and the thief hatch ADCIN15 that DSP sent into this signal again by the signal pickup assembly that is connected with K type thermocouple finishes signals sampling.Adopt wave converter to carry out wavelet transformation then, adopt wave filter to filter the HFS of signal again, can obtain desirable temperature signal, thereby realize accurate measurement miniature gas turbine turbine intake temperature to gathering the temperature signal that comes.

Those of ordinary skill in the art will be appreciated that, above embodiment is used for illustrating the utility model, and be not to be used as qualification of the present utility model, as long as in connotation scope of the present utility model, all will drop in claims scope of the present utility model the above embodiment's variation, modification.

Claims (5)

1. the temperature collecting device of a miniature gas turbine is located in the turbine control system of miniature gas turbine, it is characterized in that comprising:

One thermocouple is located at the turbine exhaust end of described miniature gas turbine, and the turbine of measuring described miniature gas turbine is in real time discharged the temperature of gas, and is electrical signal with temperature transition;

One integrated temperature sensor AD590 is connected in series with the cold junction of described thermocouple;

One signal pickup assembly is connected with the other end of described thermocouple, receives the electrical signal that thermocouple changes.

2. the temperature collecting device of miniature gas turbine as claimed in claim 1, it is characterized in that also comprising: a biasing resistor is connected in series with described integrated temperature sensor AD590.

3. the temperature collecting device of miniature gas turbine as claimed in claim 1, it is characterized in that: described thermocouple is a K type thermocouple.

4. the temperature collecting device of miniature gas turbine as claimed in claim 1 is characterized in that also comprising: a wave converter, and it is connected with described signal pickup assembly, and the electrical signal that signal pickup assembly is received carries out wavelet transformation.

5. the temperature collecting device of miniature gas turbine as claimed in claim 4, it is characterized in that also comprising: a wave filter, it is connected with described wave converter.

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