JP5723220B2

JP5723220B2 - Power plant

Info

Publication number: JP5723220B2
Application number: JP2011122343A
Authority: JP
Inventors: 川昌和白
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 2011-05-31
Filing date: 2011-05-31
Publication date: 2015-05-27
Anticipated expiration: 2031-05-31
Also published as: JP2012251670A

Description

本発明の実施形態は、発電プラント及びその運転方法に関する。 Embodiments described herein relate generally to a power plant and an operation method thereof.

太陽熱発電とは、太陽光を集光して、汽力発電の熱源として利用する発電方法である。太陽熱発電のメリットとしては、環境汚染がないことや、燃料費が不要であることなどが挙げられる。しかし、太陽熱発電には、発電の効率性を考えると、大型の設備が必要となるとともに、十分な熱量の確保のために広大な受光面積（大規模な面積の土地）が必要となるなどのデメリットがある。ゆえに、太陽熱発電のみで、火力発電の代替となる大容量電源の発電設備を構成することは困難である。 Solar power generation is a power generation method that collects sunlight and uses it as a heat source for steam power generation. Advantages of solar thermal power generation include no environmental pollution and no fuel costs. However, considering the efficiency of power generation, solar power generation requires large facilities and a large light receiving area (land with a large area) to secure a sufficient amount of heat. There are disadvantages. Therefore, it is difficult to construct a power generation facility with a large-capacity power source that can replace thermal power generation using only solar thermal power generation.

そこで、従来の火力発電と太陽熱発電とを組み合わせた様々な汽力発電システムが考案されている。例えば、ボイラに供給する水を温める給水加熱器の一部に、太陽熱を利用する方法が考案されており、図１０を参照して説明する。 Therefore, various steam power generation systems combining conventional thermal power generation and solar power generation have been devised. For example, a method of utilizing solar heat has been devised for a part of a feed water heater for warming water supplied to a boiler, which will be described with reference to FIG.

図１０は、従来の発電プラントの構成を示す概略的な構成図である。図１０の発電プラントは、火力発電と太陽熱発電とを組み合わせた汽力発電システムに相当する。 FIG. 10 is a schematic configuration diagram showing a configuration of a conventional power plant. The power plant in FIG. 10 corresponds to a steam power generation system that combines thermal power generation and solar thermal power generation.

図１０の発電プラントでは、燃料Ｆを燃料流量調節弁Ｖ１からボイラ１に供給し、ボイラ１で燃料Ｆを燃やして、水から蒸気を発生させる。この蒸気Ｓ１を蒸気タービン２のガバナ弁Ｖ２に導いて、蒸気タービン２を回し、発電機３により回転エネルギーを電気エネルギーに変換する。 In the power plant of FIG. 10, the fuel F is supplied to the boiler 1 from the fuel flow control valve V1, the fuel F is burned by the boiler 1, and steam is generated from water. The steam S1 is guided to the governor valve V2 of the steam turbine 2, the steam turbine 2 is rotated, and the generator 3 converts rotational energy into electric energy.

蒸気タービン２を回した排気蒸気Ｓ２は、図示しない復水器で冷やして水に戻される。この水Ｗ１を給水ポンプ４にて昇圧し、給水流量調節弁Ｖ３に導いて、蒸気熱利用の給水加熱器５に流入させる。 The exhaust steam S2 that has rotated the steam turbine 2 is cooled by a condenser (not shown) and returned to water. The water W1 is boosted by the feed water pump 4, led to the feed water flow rate adjustment valve V3, and flows into the feed water heater 5 using steam heat.

蒸気タービン２の中間段から抽気される蒸気は、抽気逆止弁Ｖ４を経て、蒸気熱利用の給水加熱器５に流入する抽気蒸気Ｓ３となる。蒸気熱利用の給水加熱器５の伝熱管内で水が温められるとともに、伝熱管外の抽気蒸気が冷やされる。この抽気蒸気は、冷やされてドレン水となり、器内に溜まる。このドレン水の水位計測値Ｉ１が所定の水位となるように、給水加熱器ドレン水位調節弁Ｖ５が制御され、ドレン水Ｗ３が蒸気熱利用の給水加熱器５から流出される。 The steam extracted from the intermediate stage of the steam turbine 2 becomes the extracted steam S3 flowing into the feed water heater 5 using steam heat through the extraction check valve V4. Water is warmed in the heat transfer pipe of the feed water heater 5 using steam heat, and the extracted steam outside the heat transfer pipe is cooled. The extracted steam is cooled to become drain water and accumulates in the vessel. The feed water heater drain level control valve V5 is controlled so that the drain water level measurement value I1 becomes a predetermined water level, and the drain water W3 flows out of the feed water heater 5 utilizing steam heat.

蒸気熱利用の給水加熱器５で温められた水は、太陽熱利用の給水加熱器６に流入し、太陽からの入熱量Ｑによりさらに温められ、ボイラ１に供給される水Ｗ２となる。 The water heated by the steam-heated feed water heater 5 flows into the solar-heated feed water heater 6, further warmed by the heat input amount Q from the sun, and becomes water W <b> 2 supplied to the boiler 1.

次に、図１０を参照し、従来の発電プラントにおける蒸気の温度変動の抑制方法とその問題点について説明する。 Next, with reference to FIG. 10, a method for suppressing temperature fluctuations of steam in a conventional power plant and its problems will be described.

ボイラ１が貫流ボイラの場合は、太陽からの日射量が変動すると、ボイラ１の蒸発部内で水から蒸気への蒸発完了点が変動する。 When the boiler 1 is a once-through boiler, when the amount of solar radiation fluctuates, the point of completion of evaporation from water to steam fluctuates in the evaporation section of the boiler 1.

例えば、太陽からの日射量が増加すると、入熱量Ｑも増加するため、太陽熱利用の給水加熱器６を通過後の水Ｗ２の温度が上昇し、ボイラ１に供給される水の温度も上昇する。この結果、ボイラ１の蒸発部内で水から蒸気への蒸発完了点が上流側に移動して過熱部が相対的に長くなるため、過熱部出口の蒸気の温度が上昇し、ボイラ１の出口部の蒸気Ｓ１の温度も上昇する。 For example, when the amount of solar radiation from the sun increases, the amount of heat input Q also increases, so the temperature of the water W2 after passing through the solar-heated feed water heater 6 rises and the temperature of the water supplied to the boiler 1 also rises. . As a result, the point of completion of evaporation from water to steam moves upstream in the evaporation part of the boiler 1 and the superheated part becomes relatively long. The temperature of the steam S1 also increases.

逆に、太陽からの日射量が減少すると、入熱量Ｑも減少するため、太陽熱利用の給水加熱器６を通過後の水Ｗ２の温度が低下し、ボイラ１に供給される水の温度も低下する。この結果、ボイラ１の蒸発部内で水から蒸気への蒸発完了点が下流側に移動して過熱部が相対的に短くなるため、過熱部出口の蒸気の温度が低下し、ボイラ１の出口部の蒸気Ｓ１の温度も低下する。 Conversely, if the amount of solar radiation from the sun decreases, the heat input Q also decreases, so the temperature of the water W2 after passing through the solar water heating heater 6 decreases and the temperature of the water supplied to the boiler 1 also decreases. To do. As a result, the evaporation completion point from water to steam moves downstream in the evaporation part of the boiler 1 and the superheated part becomes relatively short, so that the temperature of the steam at the outlet of the superheated part decreases, and the outlet part of the boiler 1 The temperature of the steam S1 also decreases.

このような蒸気の温度変動を抑えるため、太陽からの日射量が増加して、蒸気Ｓ１の温度が上昇した場合には、燃料流量調節弁Ｖ１を閉じて、ボイラ１に投入する燃料Ｆの流量を減少させる。逆に、太陽からの日射量が減少し、蒸気Ｓ１の温度が低下した場合には、燃料流量調節弁Ｖ１を開けて、ボイラ１に投入する燃料Ｆの流量を増加させる。 In order to suppress such temperature fluctuations of the steam, when the amount of solar radiation increases from the sun and the temperature of the steam S1 rises, the fuel flow rate control valve V1 is closed and the flow rate of the fuel F to be introduced into the boiler 1 Decrease. Conversely, when the amount of solar radiation from the sun decreases and the temperature of the steam S1 decreases, the fuel flow rate control valve V1 is opened to increase the flow rate of the fuel F to be introduced into the boiler 1.

この作動原理は、太陽からの日射量が増加するほど、ボイラ１に投入する燃料Ｆの流量を減少でき、燃料費を抑えられることを意味している。 This operating principle means that as the amount of solar radiation from the sun increases, the flow rate of the fuel F input to the boiler 1 can be reduced, and the fuel cost can be reduced.

しかし、ボイラ１の熱容量は大きいため、太陽からの日射量が大きく変動すると、蒸気の温度変動を短時間内に許容される範囲内に抑えることができなくなる。そのため、ボイラ１や、蒸気タービン２や、蒸気Ｓ１が流動する蒸気配管の金属部などで、熱応力の繰返しによる熱疲労損傷が生じるという問題がある。 However, since the heat capacity of the boiler 1 is large, if the amount of solar radiation from the sun fluctuates greatly, it becomes impossible to suppress the temperature fluctuation of the steam within the allowable range within a short time. Therefore, there is a problem that thermal fatigue damage due to repeated thermal stress occurs in the boiler 1, the steam turbine 2, or the metal part of the steam pipe through which the steam S <b> 1 flows.

また、ボイラ１の燃料流量調節弁Ｖ１と、ボイラ１の過熱器スプレー水量を制御する温度調節弁（不図示）との干渉や、蒸気タービン２のガバナ弁Ｖ２や給水流量調節弁Ｖ３の制御との干渉が発生し、ボイラ制御やタービン制御が不安定化するという問題もある。 Further, interference between the fuel flow rate control valve V1 of the boiler 1 and a temperature control valve (not shown) for controlling the superheater spray water amount of the boiler 1, and control of the governor valve V2 and the feed water flow rate control valve V3 of the steam turbine 2 There is also a problem that boiler control and turbine control become unstable.

社団法人、火力原子力発電技術協会、火原限協会講座（２１）、「計測制御と自動化」（平成６年６月発行）、第３３〜３６頁Incorporated Association, Thermal Power Generation Technology Association, Fire Field Limit Association Lecture (21), “Measurement Control and Automation” (June 1994), pp. 33-36

太陽熱を利用する発電プラント（汽力発電システム）は、天候の変化により太陽からの日射量が変動するため、それに応じて運転状態も変動することになる。特に、日本のように日中に天気が晴れ、曇り、雨と不規則に大きく変化することが多い地域では、太陽熱を利用する発電プラントの運転状態も頻繁に大きく変動することになる。 In a power plant (steam power generation system) that uses solar heat, the amount of solar radiation from the sun fluctuates due to changes in the weather, and the operating state fluctuates accordingly. In particular, in an area where the weather is often sunny, cloudy, and rainy, such as in Japan, where the weather frequently changes irregularly, the operating state of the power plant that uses solar heat also frequently fluctuates greatly.

しかしながら、従来の発電プラントでは、太陽からの日射量が大きく変動すると、ボイラ１や、蒸気タービン２や、蒸気Ｓ１が流動する蒸気配管の金属部などで熱疲労損傷が生じたり、ボイラ制御やタービン制御が不安定化するという問題が発生する。 However, in the conventional power plant, when the amount of solar radiation from the sun fluctuates greatly, thermal fatigue damage may occur in the boiler 1, the steam turbine 2, the metal part of the steam pipe through which the steam S1 flows, etc. There arises a problem that the control becomes unstable.

そこで、本発明は、太陽からの日射量が大きく変動しても、蒸気の温度変動を小さく抑えることで、発電プラントを構成する部材の熱疲労損傷を軽減し、かつ、調節弁間の制御干渉を少なくすることで、ボイラ制御やタービン制御を安定化させることを目的とする。 Therefore, the present invention reduces thermal fatigue damage of the members constituting the power plant even if the amount of solar radiation from the sun fluctuates greatly, and reduces control fatigue between the control valves. The purpose is to stabilize boiler control and turbine control by reducing.

一の実施形態によれば、発電プラントは、水を加熱して蒸気を発生させるボイラと、前記ボイラからの蒸気で発電機を駆動させる蒸気タービンとを備える。さらに、前記プラントは、前記蒸気タービンから排気又は抽気された蒸気の熱を利用して、前記ボイラに供給する水を温める、蒸気熱利用の給水加熱器と、太陽光を集光させて発生する熱を利用して、前記ボイラに供給する水を温める、太陽熱利用の給水加熱器とを備える。さらに、前記プラントは、前記蒸気熱利用の給水加熱器の入口に向けて水を流すための第１の水経路と、前記蒸気熱利用の給水加熱器の出口から排出された水を流すための第２の水経路と、前記蒸気熱利用の給水加熱器をバイパスして前記第１の水経路から前記第２の水経路に水を流すための第３の水経路とを備える。さらに、前記プラントは、前記第２又は第３の水経路内を流れる水の温度を計測する温度計測器と、前記温度に基づいて、前記第１の水経路上の分配弁と前記第３の水経路上の分配弁とを制御する、又は前記第１の水経路と前記第３の水経路との合流地点上の三方弁を制御する制御器とを備える。 According to one embodiment, a power generation plant includes a boiler that heats water to generate steam and a steam turbine that drives a generator with steam from the boiler. Further, the plant is generated by condensing sunlight and a feed water heater using steam heat that heats water supplied to the boiler by using heat of steam exhausted or extracted from the steam turbine. A solar water heating heater that heats water supplied to the boiler using heat; The plant further includes a first water path for flowing water toward an inlet of the water heater using steam heat, and water discharged from an outlet of the water heater using steam heat. A second water path; and a third water path for allowing water to flow from the first water path to the second water path, bypassing the water heater using steam heat. Furthermore, the plant includes a temperature measuring instrument that measures a temperature of water flowing in the second or third water path, a distribution valve on the first water path, and the third based on the temperature. A controller for controlling a distribution valve on the water path, or for controlling a three-way valve on the junction of the first water path and the third water path.

また、別の実施形態によれば、発電プラントの運転方法は、水を加熱して蒸気を発生させるボイラからの蒸気を、前記ボイラからの蒸気で発電機を駆動させる蒸気タービンに搬送するための経路上のガバナ弁と、前記ボイラに供給する水の流量と、前記ボイラに供給する燃料の流量とを、ボイラ・タービン協調制御方式に基づいて各々制御することにより、前記発電機の発電量を制御する。 According to another embodiment, the operation method of the power plant is for transporting steam from a boiler that generates steam by heating water to a steam turbine that drives a generator with steam from the boiler. By controlling the governor valve on the path, the flow rate of water supplied to the boiler, and the flow rate of fuel supplied to the boiler based on a boiler-turbine cooperative control system, the power generation amount of the generator is controlled. Control.

第１実施形態の発電プラントの構成を示す概略的な構成図である。It is a schematic block diagram which shows the structure of the power plant of 1st Embodiment. 第２実施形態の発電プラントの構成を示す概略的な構成図である。It is a schematic block diagram which shows the structure of the power plant of 2nd Embodiment. 第３実施形態の発電プラントの構成を示す概略的な構成図である。It is a schematic block diagram which shows the structure of the power plant of 3rd Embodiment. 第４実施形態の発電プラントの構成を示す概略的な構成図である。It is a schematic block diagram which shows the structure of the power plant of 4th Embodiment. 第５実施形態の発電プラントの構成を示す概略的な構成図である。It is a schematic block diagram which shows the structure of the power plant of 5th Embodiment. 第６実施形態の発電プラントの構成を示す概略的な構成図である。It is a schematic block diagram which shows the structure of the power plant of 6th Embodiment. 第７実施形態の発電プラントの構成を示す概略的な構成図である。It is a schematic block diagram which shows the structure of the power plant of 7th Embodiment. 第８実施形態の発電プラントの構成を示す概略的な構成図である。It is a schematic block diagram which shows the structure of the power plant of 8th Embodiment. 第１実施形態の変形例の発電プラントの構成を示す概略的な構成図である。It is a schematic block diagram which shows the structure of the power plant of the modification of 1st Embodiment. 従来の発電プラントの構成を示す概略的な構成図である。It is a schematic block diagram which shows the structure of the conventional power plant.

以下、本発明の実施形態を、図面を参照して説明する。なお、各図で共通する要素には同一符号を付けている。 Embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected to the element which is common in each figure.

［第１実施形態］
図１は、第１実施形態の発電プラントの構成を示す概略的な構成図である。 [First Embodiment]
FIG. 1 is a schematic configuration diagram showing the configuration of the power plant according to the first embodiment.

図１では、復水器からの水Ｗ１を、給水ポンプ４にて昇圧し、給水流量調節弁Ｖ３に導いて、水Ｗ４と水Ｗ５に分岐させる。水Ｗ４は、蒸気熱利用の給水加熱器５の入口へと流入し、水Ｗ５は、蒸気熱利用の給水加熱器５をバイパスする。水Ｗ１が流れる水経路と、水Ｗ４を蒸気熱利用の給水加熱器５の入口へと流入させる水経路は、本発明の第１の水経路の例である。また、水Ｗ５が流れる水経路は、本発明の第３の水経路の例である。 In FIG. 1, the water W1 from the condenser is boosted by the feed water pump 4 and led to the feed water flow rate adjustment valve V3 to be branched into water W4 and water W5. The water W4 flows into the inlet of the feed water heater 5 using steam heat, and the water W5 bypasses the feed water heater 5 using steam heat. The water path through which the water W1 flows and the water path through which the water W4 flows into the inlet of the feed water heater 5 using steam heat are examples of the first water path of the present invention. The water path through which the water W5 flows is an example of the third water path of the present invention.

蒸気熱利用の給水加熱器５は、抽気蒸気Ｓ３の熱を利用して水Ｗ４を温め、蒸気熱利用の給水加熱器５の出口から排出する。排出された水Ｗ４は、水Ｗ５と合流して、水Ｗ２となる。なお、蒸気熱利用の給水加熱器５は、蒸気タービン２の出口から排出された蒸気を利用して、水Ｗ４を温めても構わない。合流後の水Ｗ２は、太陽熱利用の給水加熱器６の入口へと流入する。 The feed water heater 5 using steam heat warms the water W4 using the heat of the extracted steam S3 and discharges it from the outlet of the feed water heater 5 using steam heat. The discharged water W4 merges with the water W5 to become water W2. Note that the feed water heater 5 using steam heat may warm the water W <b> 4 using the steam discharged from the outlet of the steam turbine 2. The merged water W2 flows into the inlet of the feed water heater 6 using solar heat.

太陽熱利用の給水加熱器６は、太陽光を集光させて発生する熱を利用して水Ｗ２をさらに温め、太陽熱利用の給水加熱器６の出口から排出する。排出された水Ｗ２は、ボイラ２へと供給される。蒸気熱利用の給水加熱器５の出口から排出された水Ｗ４が流れる水経路と、水Ｗ５が流れる水経路は、本発明の第２の水経路の例である。 The solar-powered water heater 6 further heats the water W2 using heat generated by collecting sunlight and discharges it from the outlet of the solar-heated water heater 6. The discharged water W2 is supplied to the boiler 2. The water path through which the water W4 discharged from the outlet of the feed water heater 5 utilizing steam heat flows and the water path through which the water W5 flows are examples of the second water path of the present invention.

図１の発電プラントはさらに、符号Ｔで示すように、太陽熱利用の給水加熱器６から排出された水Ｗ２の温度を計測する温度計測器を備えている。温度計測器から出力された温度計測値Ｉ２の信号は、給水流量分配制御器Ｃ１に入力される。 The power plant in FIG. 1 further includes a temperature measuring device that measures the temperature of the water W2 discharged from the feed water heater 6 using solar heat, as indicated by a symbol T. The signal of the temperature measurement value I2 output from the temperature measuring device is input to the feed water flow rate distribution controller C1.

そして、給水流量分配制御器Ｃ１は、温度計測値Ｉ２に基づいて、第１の給水流量分配弁Ｖ６と、第２の給水流量分配弁Ｖ７とを制御する。第１の給水流量分配弁Ｖ６は、水Ｗ４を蒸気熱利用の給水加熱器５の入口に向けて流す水経路（第１の水経路）上に設置されている。また、第２の給水流量分配弁Ｖ７は、水Ｗ５が流れる水経路（第３の水経路）上に設置されている。 Then, the water supply flow distribution controller C1 controls the first water supply flow distribution valve V6 and the second water supply flow distribution valve V7 based on the temperature measurement value I2. The first water supply flow distribution valve V6 is installed on a water path (first water path) through which the water W4 flows toward the inlet of the feed water heater 5 using steam heat. In addition, the second water supply flow distribution valve V7 is installed on a water path (third water path) through which the water W5 flows.

具体的には、給水流量分配制御器Ｃ１は、温度計測器により計測される水Ｗ２の温度が所定の一定温度となるように、給水流量分配弁Ｖ６の開度指令値Ｃ２と、給水流量分配弁Ｖ７の開度指令値Ｃ３とを出力する。こうして、給水流量分配制御器Ｃ１は、蒸気熱利用の給水加熱器５の入口に流入する水Ｗ４の流量と、蒸気熱利用の給水加熱器５をバイパスする水Ｗ５の流量を制御する。 Specifically, the feed water flow distribution controller C1 determines the opening command value C2 of the feed water flow distribution valve V6 and the feed water flow distribution so that the temperature of the water W2 measured by the temperature measuring device becomes a predetermined constant temperature. An opening command value C3 of the valve V7 is output. Thus, the feed water flow distribution controller C1 controls the flow rate of the water W4 flowing into the inlet of the feed water heater 5 utilizing steam heat and the flow rate of the water W5 bypassing the feed water heater 5 utilizing steam heat.

なお、図１０と同一符号を付けたその他の要素の動作については、図１０と同様であるため、重複した説明は省略することにする。 The operations of other elements having the same reference numerals as those in FIG. 10 are the same as those in FIG.

（第１実施形態の作用効果）
以下、第１実施形態の作用効果について説明する。 (Operational effects of the first embodiment)
Hereinafter, the effect of the first embodiment will be described.

図１の発電プラントでは、太陽からの日射量が増加すると、入熱量Ｑも増加するが、本実施形態では、ボイラ１に供給される水Ｗ２の温度の上昇を抑えるために、給水流量分配弁Ｖ７の開度を上げて、給水流量分配弁Ｖ６の開度を下げることで、水Ｗ２の温度を所定の一定温度に制御することができる。 In the power plant of FIG. 1, when the amount of solar radiation increases, the amount of heat input Q also increases. However, in this embodiment, in order to suppress an increase in the temperature of the water W2 supplied to the boiler 1, a feed water flow distribution valve The temperature of the water W2 can be controlled to a predetermined constant temperature by increasing the opening of V7 and decreasing the opening of the feed water flow distribution valve V6.

逆に、太陽からの日射量が減少すると、入熱量Ｑも減少するが、本実施形態では、ボイラ１に供給される水Ｗ２の温度の低下を抑えるために、給水流量分配弁Ｖ７の開度を下げて、給水流量分配弁Ｖ６の開度を上げることで、水Ｗ２の温度を所定の一定温度に制御することができる。 Conversely, when the amount of solar radiation from the sun decreases, the amount of heat input Q also decreases. However, in this embodiment, in order to suppress a decrease in the temperature of the water W2 supplied to the boiler 1, the opening of the feed water flow distribution valve V7 The temperature of the water W2 can be controlled to a predetermined constant temperature by lowering and increasing the opening of the feed water flow distribution valve V6.

このように、本実施形態では、太陽からの日射量に応じて流量分配を調節することで、水Ｗ２の温度を所定の一定温度に制御することができる。流量分配による時間応答は比較的速いため、太陽からの日射量が大きく変動しても、水Ｗ２の温度を所定の一定温度に制御することが可能である。 Thus, in this embodiment, the temperature of the water W2 can be controlled to a predetermined constant temperature by adjusting the flow distribution according to the amount of solar radiation from the sun. Since the time response by flow distribution is relatively fast, even if the amount of solar radiation from the sun fluctuates greatly, the temperature of the water W2 can be controlled to a predetermined constant temperature.

また、本実施形態では、太陽からの日射量の変動の影響を、発電量の増減として取り出すことができる。 Moreover, in this embodiment, the influence of the fluctuation | variation of the solar radiation amount from the sun can be taken out as increase / decrease in power generation amount.

例えば、太陽からの日射量が増加すると、蒸気熱利用の給水加熱器５に流入する水Ｗ４の流量を減少させるため、水Ｗ４と抽気蒸気Ｓ３との交換熱量が減少する。そのため、ドレン水Ｗ３の流量が減少し、ドレン水位調節弁Ｖ５の開度が減少し、抽気蒸気Ｓ３が減少する。その結果、蒸気タービン２を回転させた排気蒸気Ｓ２が増加するため、発電機３の発電量が増加する。 For example, if the amount of solar radiation from the sun increases, the flow rate of the water W4 flowing into the feed water heater 5 using steam heat is decreased, so that the amount of heat exchanged between the water W4 and the extracted steam S3 decreases. Therefore, the flow rate of the drain water W3 decreases, the opening degree of the drain water level control valve V5 decreases, and the extraction steam S3 decreases. As a result, the exhaust steam S2 obtained by rotating the steam turbine 2 increases, so that the power generation amount of the generator 3 increases.

逆に、太陽からの日射量が減少すると、蒸気熱利用の給水加熱器５に流入する水Ｗ４の流量を増加させるため、水Ｗ４と抽気蒸気Ｓ３との交換熱量が増加する。そのため、ドレン水Ｗ３の流量が増加し、ドレン水位調節弁Ｖ５の開度が増加し、抽気蒸気Ｓ３が増加する。その結果、蒸気タービン２を回転させた排気蒸気Ｓ２が減少するため、発電機３の発電量が減少する。 On the other hand, when the amount of solar radiation from the sun decreases, the flow rate of the water W4 flowing into the feed water heater 5 using steam heat is increased, so the amount of heat exchanged between the water W4 and the extracted steam S3 increases. Therefore, the flow rate of the drain water W3 increases, the opening degree of the drain water level control valve V5 increases, and the extraction steam S3 increases. As a result, the exhaust steam S2 obtained by rotating the steam turbine 2 is reduced, so that the power generation amount of the generator 3 is reduced.

以上のように、本実施形態では、温度計測値Ｉ２に基づいて、第１の給水流量分配弁Ｖ６と、第２の給水流量分配弁Ｖ７とを制御する。これにより、太陽からの日射量が大きく変動しても、ボイラ１に供給される水Ｗ２の温度を一定に保てるため、ボイラ１の出口部の蒸気Ｓ１の温度も一定に保つことができる。 As described above, in the present embodiment, the first feed water flow distribution valve V6 and the second feed water flow distribution valve V7 are controlled based on the temperature measurement value I2. Thereby, even if the amount of solar radiation from the sun fluctuates greatly, the temperature of the water W2 supplied to the boiler 1 can be kept constant, so that the temperature of the steam S1 at the outlet of the boiler 1 can also be kept constant.

その結果、本実施形態では、ボイラ１や、蒸気タービン２や、蒸気Ｓ１が流動する蒸気配管の金属部などで、熱応力の繰返しによる熱疲労損傷を軽減することが可能になる。また、本実施形態では、調節弁間の制御干渉が少なくなるため、ボイラ制御やタービン制御を安定化させることが可能になる。 As a result, in the present embodiment, thermal fatigue damage due to repeated thermal stress can be reduced in the boiler 1, the steam turbine 2, the metal part of the steam pipe through which the steam S1 flows, and the like. Moreover, in this embodiment, since control interference between control valves decreases, boiler control and turbine control can be stabilized.

（第１実施形態の変形例）
図１に示す発電プラントの構成は、図９に示す構成に置き換えてもよい。図９は、第１実施形態の変形例の発電プラントの構成を示す概略的な構成図である。 (Modification of the first embodiment)
The configuration of the power plant shown in FIG. 1 may be replaced with the configuration shown in FIG. FIG. 9 is a schematic configuration diagram illustrating a configuration of a power plant according to a modification of the first embodiment.

図９の発電プラントは、第１、第２の給水流量分配弁Ｖ６、Ｖ７の代わりに、三方弁Ｖ８を備えている。三方弁Ｖ８は、水Ｗ１、Ｗ４が流れる第１の水経路と、水Ｗ５が流れる第３の水経路との合流地点上に設置されており、水Ｗ４、Ｗ５の流量を調節することができる。本変形例の給水流量分配制御器Ｃ１は、温度計測値Ｉ２に基づいて、三方弁Ｖ８を制御する。 The power plant in FIG. 9 includes a three-way valve V8 instead of the first and second feed water flow rate distribution valves V6 and V7. The three-way valve V8 is installed on the junction point of the first water path through which the water W1 and W4 flow and the third water path through which the water W5 flows, and can adjust the flow rates of the water W4 and W5. . The feed water flow distribution controller C1 of the present modification controls the three-way valve V8 based on the temperature measurement value I2.

具体的には、給水流量分配制御器Ｃ１は、温度計測器により計測される水Ｗ２の温度が所定の一定温度となるように、三方弁Ｖ８の分配指令値Ｃ１０を出力する。こうして、給水流量分配制御器Ｃ１は、蒸気熱利用の給水加熱器５の入口に流入する水Ｗ４の流量と、蒸気熱利用の給水加熱器５をバイパスする水Ｗ５の流量を制御する。 Specifically, the feed water flow distribution controller C1 outputs the distribution command value C10 of the three-way valve V8 so that the temperature of the water W2 measured by the temperature measuring device becomes a predetermined constant temperature. Thus, the feed water flow distribution controller C1 controls the flow rate of the water W4 flowing into the inlet of the feed water heater 5 utilizing steam heat and the flow rate of the water W5 bypassing the feed water heater 5 utilizing steam heat.

本変形例によれば、第１実施形態と同様、太陽からの日射量が大きく変動しても、ボイラ１に供給される水Ｗ２の温度を一定に保てるため、ボイラ１の出口部の蒸気Ｓ１の温度も一定に保つことができる。 According to this modified example, similarly to the first embodiment, even if the amount of solar radiation from the sun fluctuates greatly, the temperature of the water W2 supplied to the boiler 1 can be kept constant, so that the steam S1 at the outlet of the boiler 1 The temperature can be kept constant.

よって、本変形例によれば、ボイラ１や、蒸気タービン２や、蒸気Ｓ１が流動する蒸気配管の金属部などで、熱応力の繰返しによる熱疲労損傷を軽減することが可能になる。また、本変形例によれば、調節弁間の制御干渉が少なくなるため、ボイラ制御やタービン制御を安定化させることが可能になる。 Therefore, according to this modification, it is possible to reduce thermal fatigue damage due to repeated thermal stresses in the boiler 1, the steam turbine 2, or the metal part of the steam pipe through which the steam S1 flows. Moreover, according to this modification, since control interference between the control valves is reduced, it is possible to stabilize boiler control and turbine control.

なお、本変形例の構成は、第１実施形態だけでなく、後述する第２から第４実施形態にも適用可能である。 In addition, the structure of this modification is applicable not only to 1st Embodiment but 2nd to 4th Embodiment mentioned later.

以下、第１実施形態の変形例である第２から第８実施形態について、第１実施形態との相違点を中心に説明する。 Hereinafter, second to eighth embodiments, which are modifications of the first embodiment, will be described focusing on differences from the first embodiment.

［第２実施形態］
図２は、第２実施形態の発電プラントの構成を示す概略的な構成図である。 [Second Embodiment]
FIG. 2 is a schematic configuration diagram illustrating the configuration of the power plant according to the second embodiment.

図２では、復水器からの水Ｗ１を、給水ポンプ４にて昇圧し、給水流量調節弁Ｖ３に導いて、太陽熱利用の給水加熱器６の入口へと流入させる。太陽熱利用の給水加熱器６は、太陽光を集光させて発生する熱を利用して水Ｗ１を温め、太陽熱利用の給水加熱器６の出口から排出する。排出された水Ｗ１は、水Ｗ４と水Ｗ５に分岐される。水Ｗ４は、蒸気熱利用の給水加熱器５の入口へと流入し、水Ｗ５は、蒸気熱利用の給水加熱器５をバイパスする。 In FIG. 2, the water W1 from the condenser is boosted by the feed water pump 4 and led to the feed water flow rate adjustment valve V3 to flow into the inlet of the feed water heater 6 using solar heat. The solar-powered feed water heater 6 warms the water W1 using heat generated by collecting sunlight and discharges it from the outlet of the solar-heated feed water heater 6. The discharged water W1 is branched into water W4 and water W5. The water W4 flows into the inlet of the feed water heater 5 using steam heat, and the water W5 bypasses the feed water heater 5 using steam heat.

蒸気熱利用の給水加熱器５は、抽気蒸気Ｓ３の熱を利用して水Ｗ４をさらに温め、蒸気熱利用の給水加熱器５の出口から排出する。排出された水Ｗ４は、水Ｗ５と合流して、水Ｗ２となる。合流後の水Ｗ２は、ボイラ２へと供給される。 The feed water heater 5 using steam heat further warms the water W4 using the heat of the extracted steam S3 and discharges it from the outlet of the feed water heater 5 using steam heat. The discharged water W4 merges with the water W5 to become water W2. The merged water W2 is supplied to the boiler 2.

図２の発電プラントはさらに、符号Ｔで示すように、合流後の水Ｗ２の温度を計測する温度計測器を備えている。温度計測器から出力された温度計測値Ｉ２の信号は、給水流量分配制御器Ｃ１に入力される。そして、給水流量分配制御器Ｃ１は、温度計測値Ｉ２に基づいて、第１の給水流量分配弁Ｖ６と、第２の給水流量分配弁Ｖ７とを制御する。 The power plant in FIG. 2 further includes a temperature measuring instrument that measures the temperature of the water W2 after joining, as indicated by the symbol T. The signal of the temperature measurement value I2 output from the temperature measuring device is input to the feed water flow rate distribution controller C1. Then, the water supply flow distribution controller C1 controls the first water supply flow distribution valve V6 and the second water supply flow distribution valve V7 based on the temperature measurement value I2.

（第２実施形態の作用効果）
以下、第２実施形態の作用効果について説明する。 (Operational effect of the second embodiment)
Hereinafter, the function and effect of the second embodiment will be described.

図２の発電プラントでは、太陽からの日射量が増加すると、入熱量Ｑも増加するが、本実施形態では、ボイラ１に供給される水Ｗ２の温度の上昇を抑えるために、給水流量分配弁Ｖ７の開度を上げて、給水流量分配弁Ｖ６の開度を下げることで、水Ｗ２の温度を所定の一定温度に制御することができる。 In the power plant of FIG. 2, when the amount of solar radiation increases, the amount of heat input Q also increases. However, in this embodiment, in order to suppress an increase in the temperature of the water W2 supplied to the boiler 1, a feed water flow distribution valve The temperature of the water W2 can be controlled to a predetermined constant temperature by increasing the opening of V7 and decreasing the opening of the feed water flow distribution valve V6.

以上のように、本実施形態では、第１実施形態と同様に、温度計測値Ｉ２に基づいて、第１の給水流量分配弁Ｖ６と、第２の給水流量分配弁Ｖ７とを制御する。これにより、太陽からの日射量が大きく変動しても、ボイラ１に供給される水Ｗ２の温度を一定に保てるため、ボイラ１の出口部の蒸気Ｓ１の温度も一定に保つことができる。 As described above, in the present embodiment, similarly to the first embodiment, the first feed water flow rate distribution valve V6 and the second feed water flow rate distribution valve V7 are controlled based on the temperature measurement value I2. Thereby, even if the amount of solar radiation from the sun fluctuates greatly, the temperature of the water W2 supplied to the boiler 1 can be kept constant, so that the temperature of the steam S1 at the outlet of the boiler 1 can also be kept constant.

（第１実施形態と第２実施形態との比較）
次に、太陽熱利用の給水加熱器６の加熱方式などに関連して、第１実施形態と第２実施形態の作用効果に違いについて説明する。 (Comparison between the first embodiment and the second embodiment)
Next, in relation to the heating method of the feed water heater 6 using solar heat, a difference in the operational effect between the first embodiment and the second embodiment will be described.

太陽熱利用の給水加熱器６の加熱方式には、太陽熱で水を直接的に加熱する直接加熱方式と、太陽熱で熱媒体を加熱し、熱媒体で水を加熱する間接加熱方式がある。 The heating method of the feed water heater 6 using solar heat includes a direct heating method in which water is directly heated by solar heat and an indirect heating method in which a heat medium is heated by solar heat and water is heated by the heat medium.

太陽熱が水を加熱する速度は比較的遅いため、直接加熱方式を採用した太陽熱利用の給水加熱器６では、配管がガラスなどの強度の低い素材で形成されている。そのため、直接加熱方式の場合、太陽熱利用の給水加熱器６に流入させる水の温度や圧力は、できるだけ低温、低圧にすることが望ましい。 Since the rate at which solar heat heats water is relatively slow, in the solar-powered feed water heater 6 that employs the direct heating method, the piping is formed of a low-strength material such as glass. Therefore, in the case of the direct heating method, it is desirable that the temperature and pressure of water flowing into the feed water heater 6 using solar heat be as low and low pressure as possible.

よって、直接加熱方式を採用する場合には、第１実施形態の構成よりも、第２実施形態の構成を採用することが望ましい。 Therefore, when the direct heating method is adopted, it is desirable to adopt the configuration of the second embodiment rather than the configuration of the first embodiment.

一方、水を加熱する効率の観点からは、高温加熱器が上流側に位置し、低温加熱器が下流側に位置することが好ましいため、第２実施形態の構成よりも、第１実施形態の構成を採用することが望ましい。 On the other hand, from the viewpoint of the efficiency of heating water, it is preferable that the high-temperature heater is located on the upstream side and the low-temperature heater is located on the downstream side. It is desirable to adopt a configuration.

以上のように、第１、第２実施形態にはそれぞれ異なる利点があるため、いずれの構成を採用するかは、これらの利点を考慮して決定することが望ましい。 As described above, since the first and second embodiments have different advantages, it is desirable to determine which configuration is adopted in consideration of these advantages.

［第３実施形態］
図３は、第３実施形態の発電プラントの構成を示す概略的な構成図である。 [Third Embodiment]
FIG. 3 is a schematic configuration diagram illustrating the configuration of the power plant according to the third embodiment.

図３では、復水器からの水Ｗ１を給水ポンプ４にて昇圧し、給水流量調節弁Ｖ３に導いて、水Ｗ４と水Ｗ５に分岐させる。水Ｗ４は、蒸気熱利用の給水加熱器５の入口へと流入する。一方、水Ｗ５は、蒸気熱利用の給水加熱器５をバイパスして、太陽熱利用の給水加熱器６の入口へと流入する。 In FIG. 3, the water W1 from the condenser is boosted by the feed water pump 4 and led to the feed water flow rate adjusting valve V3 to be branched into water W4 and water W5. The water W4 flows into the inlet of the feed water heater 5 using steam heat. On the other hand, the water W5 bypasses the feed water heater 5 utilizing steam heat and flows into the inlet of the feed water heater 6 utilizing solar heat.

蒸気熱利用の給水加熱器５は、抽気蒸気Ｓ３の熱を利用して水Ｗ４を温め、蒸気熱利用の給水加熱器５の出口から排出する。これと並行して、太陽熱利用の給水加熱器６は、太陽光を集光させて発生する熱を利用して水Ｗ５を温め、太陽熱利用の給水加熱器６の出口から排出する。排出された水Ｗ４、Ｗ５は合流して、水Ｗ２となる。合流後の水Ｗ２は、ボイラ２へと供給される。 The feed water heater 5 using steam heat warms the water W4 using the heat of the extracted steam S3 and discharges it from the outlet of the feed water heater 5 using steam heat. In parallel with this, the feed water heater 6 using solar heat warms the water W5 using heat generated by collecting sunlight and discharges it from the outlet of the feed water heater 6 using solar heat. The discharged water W4 and W5 merge and become water W2. The merged water W2 is supplied to the boiler 2.

図３の発電プラントはさらに、符号Ｔで示すように、太陽熱利用の給水加熱器６から排出された水Ｗ５の温度を計測する温度計測器を備えている。温度計測器から出力された温度計測値Ｉ２の信号は、給水流量分配制御器Ｃ１に入力される。 The power plant in FIG. 3 further includes a temperature measuring device that measures the temperature of the water W5 discharged from the feed water heater 6 using solar heat, as indicated by a symbol T. The signal of the temperature measurement value I2 output from the temperature measuring device is input to the feed water flow rate distribution controller C1.

そして、給水流量分配制御器Ｃ１は、温度計測値Ｉ２に基づいて、第１の給水流量分配弁Ｖ６と、第２の給水流量分配弁Ｖ７とを制御する。第１の給水流量分配弁Ｖ６は、水Ｗ４を蒸気熱利用の給水加熱器５の入口に向けて流す水経路（第１の水経路）上に設置されている。また、第２の給水流量分配弁Ｖ７は、水Ｗ５を太陽熱利用の給水加熱器６の入口に向けて流す水経路（第３の水経路）上に設置されている。 Then, the water supply flow distribution controller C1 controls the first water supply flow distribution valve V6 and the second water supply flow distribution valve V7 based on the temperature measurement value I2. The first water supply flow distribution valve V6 is installed on a water path (first water path) through which the water W4 flows toward the inlet of the feed water heater 5 using steam heat. The second feed water flow distribution valve V7 is installed on a water path (third water path) through which the water W5 flows toward the inlet of the feed water heater 6 using solar heat.

具体的には、給水流量分配制御器Ｃ１は、温度計測器により計測される水Ｗ５の温度に基づいて、水Ｗ２の温度が所定の範囲内の一定温度となるように、給水流量分配弁Ｖ６の開度指令値Ｃ２と、給水流量分配弁Ｖ７の開度指令値Ｃ３とを出力する。こうして、給水流量分配制御器Ｃ１は、蒸気熱利用の給水加熱器５の入口に流入する水Ｗ４の流量と、太陽熱利用の給水加熱器６の入口に流入する水Ｗ５の流量を制御する。 Specifically, the feed water flow distribution controller C1 is configured to supply the water flow rate distribution valve V6 so that the temperature of the water W2 becomes a constant temperature within a predetermined range based on the temperature of the water W5 measured by the temperature meter. The opening command value C2 and the opening command value C3 of the feed water flow distribution valve V7 are output. Thus, the feed water flow distribution controller C1 controls the flow rate of the water W4 flowing into the inlet of the feed water heater 5 utilizing steam heat and the flow rate of the water W5 flowing into the inlet of the feed water heater 6 utilizing solar heat.

（第３実施形態の作用効果）
以下、第３実施形態の作用効果について説明する。 (Operational effect of the third embodiment)
Hereinafter, the function and effect of the third embodiment will be described.

図３の発電プラントでは、太陽からの日射量が増加すると、入熱量Ｑも増加するが、本実施形態では、太陽熱利用の給水加熱器６の出口部での水Ｗ５の温度の上昇を抑えるために、給水流量分配弁Ｖ７の開度を上げて、給水流量分配弁Ｖ６の開度を下げることで、間接的に、ボイラ１に供給される水Ｗ２の温度を、所定の範囲内の一定温度に制御することができる。 In the power generation plant of FIG. 3, when the amount of solar radiation increases, the heat input amount Q also increases. However, in this embodiment, in order to suppress an increase in the temperature of the water W5 at the outlet of the feed water heater 6 using solar heat. In addition, by increasing the opening of the feed water flow distribution valve V7 and decreasing the opening of the feed water flow distribution valve V6, the temperature of the water W2 supplied to the boiler 1 is indirectly set to a constant temperature within a predetermined range. Can be controlled.

逆に、太陽からの日射量が減少すると、入熱量Ｑも減少するが、本実施形態では、太陽熱利用の給水加熱器６の出口部での水の温度の低下を抑えるために、給水流量分配弁Ｖ７の開度を下げて、給水流量分配弁Ｖ６の開度を上げることで、間接的に、ボイラ１に供給される水Ｗ２の温度を、所定の範囲内の一定温度に制御することができる。 Conversely, when the amount of solar radiation from the sun decreases, the heat input Q also decreases, but in this embodiment, in order to suppress the decrease in the temperature of the water at the outlet of the feed water heater 6 using solar heat, the feed water flow distribution The temperature of the water W2 supplied to the boiler 1 can be indirectly controlled to a constant temperature within a predetermined range by lowering the opening of the valve V7 and increasing the opening of the feed water flow distribution valve V6. it can.

このように、本実施形態では、太陽からの日射量に応じて流量分配を調節することで、水Ｗ２の温度を所定の範囲内の一定温度に制御することができる。流量分配による時間応答は比較的速いため、太陽からの日射量が大きく変動しても、水Ｗ２の温度を所定の範囲内の一定温度に制御することが可能である。 Thus, in this embodiment, the temperature of the water W2 can be controlled to a constant temperature within a predetermined range by adjusting the flow distribution according to the amount of solar radiation from the sun. Since the time response due to the flow distribution is relatively fast, the temperature of the water W2 can be controlled to a constant temperature within a predetermined range even if the amount of solar radiation from the sun fluctuates greatly.

以上のように、本実施形態では、第１、第２実施形態と同様に、温度計測値Ｉ２に基づいて、第１の給水流量分配弁Ｖ６と、第２の給水流量分配弁Ｖ７とを制御する。これにより、太陽からの日射量が大きく変動しても、ボイラ１に供給される水Ｗ２の温度を一定に保てるため、ボイラ１の出口部の蒸気Ｓ１の温度も一定に保つことができる。 As described above, in the present embodiment, similarly to the first and second embodiments, the first feed water flow distribution valve V6 and the second feed water flow distribution valve V7 are controlled based on the temperature measurement value I2. To do. Thereby, even if the amount of solar radiation from the sun fluctuates greatly, the temperature of the water W2 supplied to the boiler 1 can be kept constant, so that the temperature of the steam S1 at the outlet of the boiler 1 can also be kept constant.

なお、第３実施形態に特有な作用効果の詳細は、第４実施形態に特有な作用効果と共に後述する。 In addition, the detail of the operation effect peculiar to 3rd Embodiment is mentioned later with the operation effect peculiar to 4th Embodiment.

［第４実施形態］
図４は、第４実施形態の発電プラントの構成を示す概略的な構成図である。 [Fourth Embodiment]
FIG. 4 is a schematic configuration diagram showing the configuration of the power plant according to the fourth embodiment.

図４の発電プラントはさらに、符号Ｔで示すように、合流後の水Ｗ２の温度を計測する温度計測器を備えている。温度計測器から出力された温度計測値Ｉ２の信号は、給水流量分配制御器Ｃ１に入力される。そして、給水流量分配制御器Ｃ１は、温度計測値Ｉ２に基づいて、第１の給水流量分配弁Ｖ６と、第２の給水流量分配弁Ｖ７とを制御する。 The power plant shown in FIG. 4 further includes a temperature measuring instrument that measures the temperature of the water W2 after joining, as indicated by the symbol T. The signal of the temperature measurement value I2 output from the temperature measuring device is input to the feed water flow rate distribution controller C1. Then, the water supply flow distribution controller C1 controls the first water supply flow distribution valve V6 and the second water supply flow distribution valve V7 based on the temperature measurement value I2.

具体的には、給水流量分配制御器Ｃ１は、温度計測器により計測される水Ｗ５の温度が所定の一定温度となるように、給水流量分配弁Ｖ６の開度指令値Ｃ２と、給水流量分配弁Ｖ７の開度指令値Ｃ３とを出力する。こうして、給水流量分配制御器Ｃ１は、蒸気熱利用の給水加熱器５の入口に流入する水Ｗ４の流量と、太陽熱利用の給水加熱器６の入口に流入する水Ｗ５の流量を制御する。 Specifically, the feed water flow distribution controller C1 determines the opening command value C2 of the feed water flow distribution valve V6 and the feed water flow distribution so that the temperature of the water W5 measured by the temperature measuring device becomes a predetermined constant temperature. An opening command value C3 of the valve V7 is output. Thus, the feed water flow distribution controller C1 controls the flow rate of the water W4 flowing into the inlet of the feed water heater 5 utilizing steam heat and the flow rate of the water W5 flowing into the inlet of the feed water heater 6 utilizing solar heat.

（第４実施形態の作用効果）
以下、第４実施形態の作用効果について説明する。 (Operational effect of the fourth embodiment)
Hereinafter, the function and effect of the fourth embodiment will be described.

図４の発電プラントでは、太陽からの日射量が増加すると、入熱量Ｑも増加するが、本実施形態では、ボイラ１に供給される水Ｗ２の温度の上昇を抑えるために、給水流量分配弁Ｖ７の開度を上げて、給水流量分配弁Ｖ６の開度を下げることで、水Ｗ２の温度を所定の範囲の一定温度に制御することができる。 In the power plant of FIG. 4, when the amount of solar radiation increases, the heat input amount Q also increases. However, in this embodiment, in order to suppress an increase in the temperature of the water W2 supplied to the boiler 1, a feed water flow distribution valve By increasing the opening of V7 and decreasing the opening of the feed water flow distribution valve V6, the temperature of the water W2 can be controlled to a constant temperature within a predetermined range.

以上のように、本実施形態では、第１〜第３実施形態と同様に、温度計測値Ｉ２に基づいて、第１の給水流量分配弁Ｖ６と、第２の給水流量分配弁Ｖ７とを制御する。これにより、太陽からの日射量が大きく変動しても、ボイラ１に供給される水Ｗ２の温度を一定に保てるため、ボイラ１の出口部の蒸気Ｓ１の温度も一定に保つことができる。 As described above, in the present embodiment, similarly to the first to third embodiments, the first feed water flow distribution valve V6 and the second feed water flow distribution valve V7 are controlled based on the temperature measurement value I2. To do. Thereby, even if the amount of solar radiation from the sun fluctuates greatly, the temperature of the water W2 supplied to the boiler 1 can be kept constant, so that the temperature of the steam S1 at the outlet of the boiler 1 can also be kept constant.

（第３実施形態と第４実施形態との比較）
次に、第３実施形態と第４実施形態の作用効果に違いについて説明する。 (Comparison between the third embodiment and the fourth embodiment)
Next, differences in the operational effects between the third embodiment and the fourth embodiment will be described.

第３、第４実施形態では共に、復水器からの水Ｗ１が水Ｗ４と水Ｗ５に分岐された後、水Ｗ４が、蒸気熱利用の給水加熱器５にて加熱され、水Ｗ５が、太陽熱利用の給水加熱器６にて加熱される。 In both the third and fourth embodiments, after the water W1 from the condenser is branched into the water W4 and the water W5, the water W4 is heated by the feed water heater 5 using steam heat, and the water W5 is It is heated by a feed water heater 6 using solar heat.

しかしながら、第３実施形態では、太陽熱利用の給水加熱器６から排出された合流前の水Ｗ５の温度が計測対象となるのに対し、第４実施形態では、合流後の水Ｗ２の温度が計測対象となる。 However, in 3rd Embodiment, while the temperature of the water W5 before the confluence | merging discharged | emitted from the feed water heater 6 using solar heat becomes a measuring object, in 4th Embodiment, the temperature of the water W2 after confluence | merging is measured. It becomes a target.

これらの実施形態では、ボイラ１に供給する水Ｗ２の温度を一定に保つことを、目標の１つとしている。そのため、水Ｗ２の温度を計測して、この計測値を一定に制御する第４実施形態の制御の方が、第３実施形態の制御よりも自然であり、この目標を達成する上で望ましい制御である。 In these embodiments, keeping the temperature of the water W2 supplied to the boiler 1 constant is one of the targets. Therefore, the control of the fourth embodiment that measures the temperature of the water W2 and controls the measured value to be constant is more natural than the control of the third embodiment, and is desirable control for achieving this target. It is.

一方、第３実施形態には、太陽からの日照量の変動が水温に及ぼす影響を、より直接的に観測できるという利点がある。理由は、第４実施形態では、水Ｗ４と水Ｗ５が混ざった後の水温を計測するため、日照量の変動による水温の変化が目立たないのに対し、第３実施形態では、水Ｗ４と混ざる前の水Ｗ５の水温を計測するため、日照量の変動による水温の変化がより明確に表れるからである。よって、第３実施形態には、日照量の変動が水温に及ぼす影響を正確に観測できる、日照量の変動の影響が水温に素早く表れる、などの利点がある。 On the other hand, 3rd Embodiment has the advantage that the influence which the fluctuation | variation of the amount of sunshine from the sun has on water temperature can be observed more directly. The reason is that in the fourth embodiment, since the water temperature after the water W4 and the water W5 are mixed is measured, the change in the water temperature due to the change in the amount of sunlight is not conspicuous, whereas in the third embodiment, the water W4 is mixed. This is because the temperature of the previous water W5 is measured, so that the change in the water temperature due to the change in the amount of sunshine appears more clearly. Therefore, the third embodiment has an advantage that the influence of the fluctuation of the sunshine amount on the water temperature can be accurately observed, and the influence of the fluctuation of the sunshine amount appears in the water temperature quickly.

なお、第３実施形態では、上述のように、温度計測器により計測される水Ｗ５の温度に基づいて、水Ｗ２の温度を所定の範囲内の一定温度となるよう制御する。このような制御は、水Ｗ２の温度、水Ｗ５の温度、第１の給水流量分配弁Ｖ６の開度、第２の給水流量分配弁Ｖ７の開度の関係を、予め実験や計算で導出しておくことで実現可能である。 In the third embodiment, as described above, the temperature of the water W2 is controlled to be a constant temperature within a predetermined range based on the temperature of the water W5 measured by the temperature measuring instrument. In such control, the relationship between the temperature of the water W2, the temperature of the water W5, the opening of the first feed water flow distribution valve V6, and the opening of the second feed water flow distribution valve V7 is derived in advance through experiments and calculations. This can be achieved.

最後に、第１、第２実施形態に対する第３、第４実施形態の利点を説明しておく。 Finally, advantages of the third and fourth embodiments over the first and second embodiments will be described.

第１、第２実施形態における太陽熱利用の給水加熱器６は、分岐前又は合流後の大量の水（Ｗ１又はＷ２）を加熱対象とする。よって、大量の水が太陽熱で加熱されるため、日照量の変動の影響による水温の変化量が大きい。 The feed water heater 6 using solar heat in the first and second embodiments uses a large amount of water (W1 or W2) before or after branching as a heating target. Therefore, since a large amount of water is heated by solar heat, the amount of change in water temperature due to the influence of fluctuations in the amount of sunlight is large.

これに対し、第３、第４実施形態における太陽熱利用の給水加熱器６は、分岐後の少量の水（Ｗ５）を加熱対象とする。よって、太陽熱で加熱される水が少量であるため、日照量の変動の影響による水温の変化量が小さい。よって、第３、第４実施形態には、第１、第２の給水流量分配弁Ｖ６、Ｖ７の制御量が小さくて済むという利点がある。 On the other hand, the feed water heater 6 using solar heat in the third and fourth embodiments uses a small amount of water (W5) after branching as a heating target. Therefore, since the amount of water heated by solar heat is small, the amount of change in water temperature due to the effect of fluctuations in the amount of sunlight is small. Therefore, the third and fourth embodiments have an advantage that the control amounts of the first and second feed water flow rate distribution valves V6 and V7 are small.

以上説明した第１から第４実施形態では、太陽からの日射量の変動により、発電機３の発電量が増減することになる。一方、電力系統周波数の安定化の観点から、発電機３の発電量を、所定の要求出力指令値に合わせて一定量に制御したい場合もあると考えられる。そこで、第５から第８実施形態では、太陽からの日射量が変動しても、発電機３の発電量を一定値に制御することが可能な発電プラントについて説明する。 In the first to fourth embodiments described above, the power generation amount of the power generator 3 increases or decreases due to fluctuations in the amount of solar radiation from the sun. On the other hand, from the viewpoint of stabilization of the power system frequency, it is considered that there is a case where it is desired to control the power generation amount of the generator 3 to a constant amount according to a predetermined required output command value. Therefore, in the fifth to eighth embodiments, a power plant capable of controlling the power generation amount of the generator 3 to a constant value even when the amount of solar radiation from the sun fluctuates will be described.

［第５〜第８実施形態］
図５〜図８はそれぞれ、第５〜第８実施形態の発電プラントの構成を示す概略的な構成図である。図５〜図８の発電プラントはそれぞれ、図１〜図４の発電プラントに対し、ボイラ・タービン協調制御方式の制御用の構成を付加したものである。 [Fifth to eighth embodiments]
FIGS. 5-8 is a schematic block diagram which respectively shows the structure of the power plant of 5th-8th Embodiment. The power plant in FIGS. 5 to 8 is obtained by adding a configuration for controlling the boiler / turbine cooperative control system to the power plant in FIGS. 1 to 4.

以下、図５を参照し、第５実施形態の発電プラントの動作について説明する。ただし、以下の説明は、第６〜第８実施形態に対しても同様に適用される。 Hereinafter, the operation of the power plant according to the fifth embodiment will be described with reference to FIG. However, the following description is similarly applied to the sixth to eighth embodiments.

図５において、要求出力指令値Ｃ４の信号は、発電機３の発電量の指令値を保持する信号である。 In FIG. 5, the signal of the required output command value C <b> 4 is a signal that holds the command value of the power generation amount of the generator 3.

本実施形態では、発電機３の発電量を指令値に制御すべく、要求出力指令値Ｃ４の信号を、発電機３の発電量計測値Ｉ３の信号と比較する。次に、指令値Ｃ４と計測値Ｉ３との偏差を修正すべく、蒸気タービン２用の制御量であるタービンガバナ指令値Ｃ５と、ボイラ１用の制御量であるボイラ入力指令値Ｃ６に対して修正を加える。タービンガバナ指令値Ｃ５は、ガバナ弁Ｖ２の開度の制御用に使用される。 In this embodiment, in order to control the power generation amount of the generator 3 to the command value, the signal of the required output command value C4 is compared with the signal of the power generation amount measurement value I3 of the generator 3. Next, in order to correct the deviation between the command value C4 and the measured value I3, a turbine governor command value C5 that is a control amount for the steam turbine 2 and a boiler input command value C6 that is a control amount for the boiler 1 are used. Make corrections. The turbine governor command value C5 is used for controlling the opening degree of the governor valve V2.

次に、本実施形態では、ボイラ入力指令値Ｃ６の信号を、ボイラ１からガバナ弁Ｖ２に向かう蒸気Ｓ１の圧力計測値Ｉ４の信号と比較する。次に、これらの値同士の偏差を修正すべく、ボイラ１用の制御量である給水指令値Ｃ７及び燃焼量指令値Ｃ８に対して修正を加える。給水指令値Ｃ７は、給水流量調節弁Ｖ３の制御、すなわち、ボイラ１に供給する水Ｗ１の流量の制御用に使用される。 Next, in this embodiment, the signal of the boiler input command value C6 is compared with the signal of the pressure measurement value I4 of the steam S1 going from the boiler 1 to the governor valve V2. Next, in order to correct the deviation between these values, correction is made to the feed water command value C7 and the combustion amount command value C8, which are control amounts for the boiler 1. The water supply command value C7 is used for controlling the water supply flow rate adjustment valve V3, that is, for controlling the flow rate of the water W1 supplied to the boiler 1.

次に、本実施形態では、燃焼量指令値Ｃ８の信号を、ボイラ１からガバナ弁Ｖ２に向かう蒸気Ｓ１の温度計測値Ｉ５の信号と比較する。次に、これらの値同士の偏差を修正すべく、ボイラ１用の制御量である燃料指令値Ｃ９に対して修正を加える。燃料指令値Ｃ９は、燃料流量調節弁Ｖ１の制御、すなわち、ボイラ１に供給する燃料Ｆの流量の制御用に使用される。 Next, in this embodiment, the signal of the combustion amount command value C8 is compared with the signal of the temperature measurement value I5 of the steam S1 going from the boiler 1 to the governor valve V2. Next, in order to correct the deviation between these values, correction is made to the fuel command value C9 that is the control amount for the boiler 1. The fuel command value C9 is used for controlling the fuel flow rate control valve V1, that is, for controlling the flow rate of the fuel F supplied to the boiler 1.

以上のボイラ・タービン協調制御の動作により修正された各制御量は、各操作端の制御ループにて調節される。すなわち、ガバナ弁Ｖ２の開度を、タービンガバナ指令値Ｃ５にバランスさせ、給水流量調節弁Ｖ３により制御される給水流量を、給水指令値Ｃ７にバランスさせ、燃料流量調節弁Ｖ１により制御される燃料流量を、燃料指令値Ｃ９にバランスさせる。この制御では、ガバナ弁Ｖ２の制御により、発電量が制御され、ガバナ弁Ｖ２の開度に釣り合うように、燃料流量調節弁Ｖ１と給水流量調節弁Ｖ３の開度が制御される。 Each control amount corrected by the operation of the above boiler / turbine cooperative control is adjusted by the control loop of each operation end. That is, the opening of the governor valve V2 is balanced with the turbine governor command value C5, the feed water flow rate controlled by the feed water flow rate control valve V3 is balanced with the feed water command value C7, and the fuel controlled by the fuel flow rate control valve V1. The flow rate is balanced to the fuel command value C9. In this control, the power generation amount is controlled by the control of the governor valve V2, and the opening amounts of the fuel flow rate adjustment valve V1 and the feed water flow rate adjustment valve V3 are controlled so as to balance the opening amount of the governor valve V2.

（第５〜第８実施形態の作用効果）
以下、第５実施形態の作用効果について説明する。ただし、以下の説明は、第６〜第８実施形態に対しても同様に適用される。 (Operational effects of the fifth to eighth embodiments)
Hereinafter, the function and effect of the fifth embodiment will be described. However, the following description is similarly applied to the sixth to eighth embodiments.

本実施形態では、第１実施形態にて説明したように、太陽からの日射量が増加すると、蒸気タービン２の抽気蒸気Ｓ３の流量を減少させる。そこで、本実施形態では、発電機３の発電量計測値Ｉ３が増加するのを抑えるために、ボイラ・タービン協調制御の動作により、ガバナ弁Ｖ２、給水流量調節弁Ｖ３、燃料流量調節弁Ｖ１の開度を下げる。これにより、発電機３の発電量計測値Ｉ３を、要求出力指令値Ｃ４に合わせて一定出力となるよう制御することができる。 In the present embodiment, as described in the first embodiment, when the amount of solar radiation from the sun increases, the flow rate of the extracted steam S3 of the steam turbine 2 is decreased. Therefore, in this embodiment, in order to suppress an increase in the power generation amount measurement value I3 of the generator 3, the governor valve V2, the feed water flow rate adjustment valve V3, and the fuel flow rate adjustment valve V1 are operated by the operation of the boiler / turbine cooperative control. Reduce the opening. As a result, the power generation amount measurement value I3 of the generator 3 can be controlled to be a constant output in accordance with the required output command value C4.

逆に、本実施形態では、太陽からの日射量が減少すると、蒸気タービン２の抽気蒸気Ｓ３の流量を増加させる。そこで、本実施形態では、発電機３の発電量計測値Ｉ３が減少するのを抑えるために、ボイラ・タービン協調制御の動作により、ガバナ弁Ｖ２、給水流量調節弁Ｖ３、燃料流量調節弁Ｖ１の開度を上げる。これにより、発電機３の発電量計測値Ｉ３を、要求出力指令値Ｃ４に合わせて一定出力となるよう制御することができる。 Conversely, in the present embodiment, when the amount of solar radiation from the sun decreases, the flow rate of the extracted steam S3 of the steam turbine 2 is increased. Therefore, in this embodiment, in order to suppress the decrease in the power generation amount measurement value I3 of the generator 3, the governor valve V2, the feed water flow rate adjustment valve V3, and the fuel flow rate adjustment valve V1 are operated by the operation of the boiler / turbine cooperative control. Increase the opening. As a result, the power generation amount measurement value I3 of the generator 3 can be controlled to be a constant output in accordance with the required output command value C4.

このような制御により、本実施形態では、太陽からの日射量が大きく変動しても、ボイラ１と蒸気タービンを１つのユニットとして統合して制御することで、汽力発電システムの主要なプロセス量である発電量、蒸気圧力、蒸気温度間の相互干渉を最小とするような制御動作を行うことができる。 With this control, in this embodiment, even if the amount of solar radiation from the sun fluctuates greatly, the boiler 1 and the steam turbine are integrated and controlled as one unit, so that the main process amount of the steam power generation system can be reduced. It is possible to perform a control operation that minimizes mutual interference among a certain amount of power generation, steam pressure, and steam temperature.

その結果、本実施形態によれば、発電量を一定値に制御する場合においても、ボイラ１や、蒸気タービン２や、蒸気Ｓ１が流動する蒸気配管の金属部などで、熱応力の繰返しによる熱疲労損傷を軽減することが可能になる。さらに、本実施形態では、調節弁間の制御干渉が少なくなるので、ボイラ制御やタービン制御を安定化させることが可能になる。 As a result, according to the present embodiment, even when the power generation amount is controlled to a constant value, heat generated by repeated thermal stresses in the boiler 1, the steam turbine 2, the metal part of the steam pipe through which the steam S 1 flows, and the like. It becomes possible to reduce fatigue damage. Furthermore, in this embodiment, since control interference between the control valves is reduced, it becomes possible to stabilize boiler control and turbine control.

なお、事業用の汽力発電システムでは、再熱サイクルや、複数の抽気段が存在する再生サイクルなどが採用されることが多い。このような汽力発電システムは、図１〜図９に示す汽力発電システムより構成が複雑であるが、このような汽力発電システムにも、第１〜第８実施形態やその変形例の構成は適用可能である。 Note that a commercial power generation system often employs a reheat cycle, a regeneration cycle having a plurality of extraction stages, and the like. Such a steam power generation system is more complicated in configuration than the steam power generation system shown in FIGS. 1 to 9, but the configurations of the first to eighth embodiments and the modifications thereof are also applied to such a steam power generation system. Is possible.

以上、本発明の具体的な態様の例を、第１から第８実施形態により説明したが、本発明は、これらの実施形態に限定されるものではない。 As mentioned above, although the example of the specific aspect of this invention was demonstrated by 1st-8th embodiment, this invention is not limited to these embodiment.

１：ボイラ、２：蒸気タービン、３：発電機、４：給水ポンプ、
５：蒸気熱利用の給水加熱器、６：太陽熱利用の給水加熱器、
Ｃ１：給水流量分配制御器、Ｃ２：第１の給水流量分配弁の開度指令値、
Ｃ３：第２の給水流量分配弁の開度指令値、Ｃ４：要求出力指令値、
Ｃ５：タービンガバナ指令値、Ｃ６：ボイラ入力指令値、
Ｃ７：給水指令値、Ｃ８：燃焼量指令値、Ｃ９：燃料指令値、
Ｉ１：給水加熱器のドレン水位計測値、Ｉ２：水の温度計測値、
Ｉ３：発電機の発電量計測値、Ｉ４：蒸気の圧力計測値、Ｉ５：蒸気の温度計測値、
Ｖ１：燃料流量調節弁、Ｖ２：ガバナ弁、Ｖ３：給水流量調節弁、
Ｖ４：タービン抽気逆止弁、Ｖ５：ドレン水位調節弁、
Ｖ６：第１の給水流量分配弁、Ｖ７：第２の給水流量分配弁、Ｖ８：三方弁、
Ｆ：燃料、Ｑ：太陽からの入熱量、
Ｓ１、Ｓ２、Ｓ３：蒸気、Ｗ１、Ｗ２、Ｗ３、Ｗ４、Ｗ５：水 1: boiler, 2: steam turbine, 3: generator, 4: feed water pump,
5: Water heater using steam heat, 6: Water heater using solar heat,
C1: feed water flow distribution controller, C2: opening command value of the first feed water flow distribution valve,
C3: Opening command value of the second feed water flow distribution valve, C4: Request output command value,
C5: turbine governor command value, C6: boiler input command value,
C7: Water supply command value, C8: Combustion amount command value, C9: Fuel command value,
I1: Drain water level measurement value of feed water heater, I2: Water temperature measurement value,
I3: power generation amount measurement value of the generator, I4: steam pressure measurement value, I5: steam temperature measurement value,
V1: Fuel flow control valve, V2: Governor valve, V3: Feed water flow control valve,
V4: Turbine bleed check valve, V5: Drain water level control valve,
V6: first water supply flow distribution valve, V7: second water supply flow distribution valve, V8: three-way valve,
F: Fuel, Q: Heat input from the sun,
S1, S2, S3: Steam, W1, W2, W3, W4, W5: Water

Claims

A boiler that generates steam by heating water;
A steam turbine that drives a generator with steam from the boiler;
Steam heat utilization water heater that warms water supplied to the boiler using heat of steam exhausted or extracted from the steam turbine;
A solar water heating heater that heats water supplied to the boiler using heat generated by collecting sunlight; and
A first water path for flowing water toward the inlet of the steam-heated feed water heater;
A second water path for flowing water discharged from an outlet of the steam-heated feed water heater;
A third water path for flowing water from the first water path to the second water path, bypassing the steam-heated feed water heater;
A temperature measuring instrument for measuring the temperature of water flowing in the second or third water path;
Based on the temperature, the distribution valve on the first water path and the distribution valve on the third water path are controlled, or the merging point between the first water path and the third water path A controller for controlling the upper three-way valve;
A power plant comprising:

The solar-powered feed water heater is disposed on the second water path downstream from the merging point of the second water path and the third water path,
The temperature measuring instrument measures the temperature of water flowing in the second water path on the downstream side of the solar-heated water heater.
The power plant according to claim 1.

The solar-powered feed water heater is disposed on the first water path upstream from the junction of the first water path and the third water path,
The temperature measuring instrument measures the temperature of the water flowing in the second water path on the downstream side of the junction of the second water path and the third water path;
The power plant according to claim 1.

The solar-heated feed water heater is disposed on the third water path,
The temperature measuring device measures the temperature of the water flowing in the third water path on the downstream side of the solar water heating heater.
The power plant according to claim 1.

The solar-heated feed water heater is disposed on the third water path,
The temperature measuring instrument measures the temperature of the water flowing in the second water path on the downstream side of the junction of the second water path and the third water path;
The power plant according to claim 1.

The controller is
A request output command value for the generator, based on the power generation amount measurement value of the generator, the turbine governor for controlling the opening of the path on the governor valve for conveying the steam from the boiler to the steam turbine Correct the command value and the boiler input command value related to the boiler,
Based on the boiler input command value and the pressure measurement value of the steam from the boiler, a water supply command value for controlling the flow rate of water supplied to the boiler, and a combustion amount command value related to the boiler are corrected,
Based on the combustion amount command value and the temperature measurement value of the steam from the boiler, the fuel command value for controlling the flow rate of fuel supplied to the boiler is corrected,
Based on the turbine governor command value, the opening degree of the governor valve is controlled, on the basis of the water supply command value, the flow rate of water supplied to the boiler is controlled, and on the basis of the fuel command value, fuel supplied to the boiler by controlling the flow rate, controls the power generation amount of the generator,
The power plant according to any one of claims 1 to 5 .