JPS59162304A - Power generator with steam turbine - Google Patents

Abstract

PURPOSE:To have efficient power generation even in the minor range of the rate of steam flow by allowing a small and a large turbine coupled with each other to rotate a generator, and by introducing the steam only to the smaller one while the rate of flow of the steam is below a specific value. CONSTITUTION:A power generator 4 is rotated by a small 2 and a large 3 turbine. When steam generation from a steam generating device 5 is less, a steam control valve 9 is shut, and another steam control valve 8 is throttled to a proper level. If the steam S is introduced preferably to the small turbine 2, the large one 3 will idle. That will provide efficient power generation even in the minor range or the rate of steam flow to ensure suppressed cost for equipment.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a steam turbine device capable of generating effective power in response to varying steam flow rates.

In recent years, with the advancement of energy conservation in various industries, it has become common to generate electricity in-house by introducing steam that replaces surplus or recovered energy into turbines, but normally the amount of steam generated in factories is It may vary significantly depending on the season and time of day.

Therefore, there is a demand for a steam turbine power generation device that can effectively generate power not only near the design point but also when the flow rate is extremely low. In order to meet these demands, installing multiple steam turbine generators to handle fluctuating steam volumes would require a large amount of capital investment and would complicate operations such as starting and stopping the equipment. There is a problem.

Therefore, the present invention was made in order to efficiently cope with the fluctuations in the amount of steam generated, and to economically install a steam turbine power generation device that can effectively generate electricity even in a low flow rate region. This is the purpose.

That is, the steam turbine power generation device of the present invention is characterized in that a generator is rotated by a small turbine and a large turbine coupled together, and steam is introduced only to the small turbine when the flow rate of steam is small below a predetermined amount.

An embodiment of the present invention will be described below with reference to the drawings, and FIG. 1 is a schematic system diagram of a turbine generator according to an embodiment of the present invention.

First, the steam turbine power generation device of the present invention comprises a small turbine 2 and a large turbine 6 connected via a reducer 1 having an appropriate reduction ratio, and furthermore, a small turbine 2 and a large turbine B driven by steam as shown by arrow S. It is composed of a generator 4 which is rotated by the engine. Steam S supplied from a steam generator 5 installed in a factory or the like is passed through a steam supply pipe 6.
The steam is supplied to the small turbine 2 and the large turbine B via the steam turbine main stop valve 7 and the steam control valves 8 and 9, respectively. The steam S generated by rotational energy to each turbine is discharged through a steam exhaust pipe 10.
11 and is introduced into the condenser 12. The condensed water W is circulated again to the steam generator 5 by the water supply pump 13. In this embodiment, when the rated flow rate of steam is obtained, the steam control valve 8.9 is opened, the small turbine and the large turbine are each operated at the rated output, and the generator generates electricity at the rated output.

On the other hand, if the amount of steam generated is extremely small, the steam control valve 9
Close the steam control valve 8 and make appropriate adjustments to throttle the steam control valve 8 to allow the steam S to flow preferentially to the small turbine 2, causing the large turbine 6 to idle, or in some cases, close the steam control valve 8 and further reduce the steam flow. By appropriately adjusting the control valve 9 to throttle it, the steam S is preferentially flowed only to the large turbine, and the small turbine 2 is caused to idle. At this time, if the large turbine or small turbine is completely idle, the minimum necessary amount of steam is used for cooling when the turbine is heated due to blade windage loss, and for heating when warm-up is necessary in preparation for ventilation after air cutoff. For use, it is supplied via line 14 to small or large turbines or other turbines.

The pipe 14 is provided with a valve 15 which is closed when there is no need to supply cooling or heating steam, that is, when the turbine is not running idly or is not being warmed up in preparation for ventilation. shall be. As a result, when the amount of steam is extremely small, the power is consumed due to idle running of the large turbine 3 or the small turbine 2, but it is much more efficient than generating electricity with a single steam turbine. Therefore, the steam turbine power generation device of the present invention has the advantage that it can efficiently generate electricity even when the amount of steam supplied is small.

The control device 16 receives a main steam pressure signal 17 or a rotational speed signal 18 to control the steam turbine control valve.

As described above, the present invention combines a small turbine and a large turbine, and introduces steam only to the small turbine when the flow rate is less than a predetermined amount. Therefore, it is possible to generate electricity effectively even when the flow rate of steam is small. Become.

Further, in the present invention, only a small turbine is provided in addition to the large turbine, and the amount of capital investment can be reduced compared to the case where a plurality of steam turbine power generators are provided to cope with fluctuations in steam flow rate.

On the other hand, when considered from an operational point of view, in the embodiment of the present invention, the control system for the steam turbine is a single series, and it is possible to cope with fluctuations in the amount of steam without a switching operation, whether it is a large flow rate or a small flow rate. That is, in FIG. 1, the steam regulating valves 8 and 9 are controlled by one control device 16 so that the steam regulating valve 8 is opened first, and the steam regulating valve 9 is opened after the flow rate has increased. In this way, even when the flow rate is small, since the large turbine is rotating, not only is no switching operation required, but also the time required to start the large turbine can be shortened since it is in a warm-up operation state.

In this example, the small turbine 2 and the large turbine 6 have a capacity difference that causes a significant difference in rotational speed, which is important in terms of turbine efficiency, so the configuration is such that the two are connected via the reducer 1 to drive the generator 4. However, the present invention is not limited to this,
If the difference in turbine capacity is within a range that does not cause a difference in rotational speed while maintaining a desirable turbine efficiency, the reducer 1 can be omitted and the two can be directly connected to drive the generator 4.

Example Comparing the operational power generation results of the device of this example (see Figures 1a, 1, and 1c) and the case where one steam turbine is operated in the entire flow range, it is found that the steam amount is 12T/H, 17T/H, 17T/H, 6T/H,
121T/H1 And when the respective operating times are 110 days/year, 180 days/year, and 60 days/year (however, this includes the two cases of driving only large turbines and driving small and large turbines) If this is generated using one steam turbine, the amount of power generated is 4.35 x 107 KWH/year, whereas in the embodiment of the present invention, the amount of electricity generated is 4.5
2 x 107KWH 7 years of electricity is obtained, which is a 4% increase in electricity.

Incidentally, the performance when the apparatus of this embodiment and one steam turbine are operated in the entire flow range is shown in FIG. 2, with the former shown as a broken line and the latter shown as a solid line.

As is clear from the figure, in this embodiment, when the steam flow rate is reduced, the steam consumption rate is reduced, resulting in a reduction in electric power cost.

[Brief explanation of the drawing]

FIGS. 1a, b, and c are schematic system diagrams of a steam turbine/power generation device according to an embodiment of the present invention, and FIG. 2 is a performance comparison diagram of the device of the present invention and one steam turbine. DESCRIPTION OF SYMBOLS 1... Reduction gear, 2... Small turbine, 6... Large turbine, 4... Generator, 5... Steam generator, 6
...Steam supply pipe line, 7...Steam turbine main stop valve, 8
, 9... Steam control valve, 10, 11... Steam discharge pipe, 12... Condenser, 13... Water supply pump, 14...
...Pipeline, 15...Valve, 16...Control device, 1
7... Main steam pressure signal, 18... Rotation speed signal. Agent: Patent Attorney Makoto Ogawa − Patent Attorney: Ken Noguchi Patent Attorney: Kazuhiko Saishita

Claims (1)

[Claims] A steam turbine power generation device characterized in that a small turbine driven by steam and rotating a generator is coupled to a large turbine, and steam is introduced only to the small turbine when the flow rate is small below a predetermined amount.