JP2017155739A - Power generating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power generating system capable of freely adapting for a variation in output of a renewable energy power generating plant through starting in operation in a short time even if there is no other steam turbine power generating plant being operated.SOLUTION: A power generating system 100 of this invention comprises: a steam turbine power generating plant 200 including a heat source device 1 for generating a high temperature medium 7 by heating a low temperature medium 6 by a heat source medium 5; a steam generating device 2 for generating steam through heat exchanging with the high temperature medium 7, and a steam turbine 3 driven by steam; a supply source 18 for supplying a heat medium generated through utilization of energy generated by other plant than the steam turbine power generating plant 200; a pre-heater device 32 fixed to at least one of the steam turbine 3 and the steam generating device 2; and pre-heating lines 28, 29 connecting the supply source 18 with the pre-heater device 32.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power generation system.

  In power generation plants using renewable energy represented by wind power generation, hydropower generation, solar power generation, solar thermal power generation, geothermal power generation, etc. (hereinafter referred to as renewable energy power generation plants), the amount of power generated from renewable energy is seasonal, It fluctuates depending on the weather, time zone, etc., and the response range to fluctuations in power demand is small. For this reason, in a power generation system including a renewable energy power plant, a grid turbine power plant (for example, a combined cycle power plant) is used together to stabilize system power. The steam turbine provided in this steam turbine power plant is required to shorten the start-up time (high-speed start-up) in order to stabilize the system power while suppressing the fuel consumption.

  When the steam turbine is started, the turbine rotor (rotary body) and the casing (stationary portion) that houses the turbine rotor are heated by being exposed to high-temperature steam, and are particularly expanded in the turbine axial direction (thermal elongation) due to thermal expansion. Since the turbine rotor and the casing have different structures and heat capacities, there is a difference (thermal expansion difference) between the thermal elongation of the turbine rotor and the casing. When this difference in thermal expansion becomes large, the turbine rotor and the casing may come into contact with each other and be damaged.

  Since the casing has a larger heat capacity than the turbine rotor, in general, the lower the casing temperature at the start of startup, the greater the difference in thermal expansion. Therefore, there is a method for controlling the start of the steam turbine by properly using a plurality of start modes such as a hot mode, a warm mode, and a cold mode according to the elapsed time after the stop of the steam turbine or the temperature inside the casing.

  However, among the plurality of start modes, in the start modes other than the hot mode (for example, the warm mode and the cold mode), the steam turbine is not sufficiently preheated, so that a difference in thermal expansion is likely to occur, and the start time of the steam turbine is lengthened. I have to set it. Therefore, a method has been proposed in which a plurality of combined cycle power plants are connected by piping and steam is supplied to a combined cycle power plant that is started up from an operating combined cycle power plant to preheat a steam turbine (Patent Document 1). Etc.).

US Pat. No. 6,199,927

  In patent document 1, when all the several combined cycle power plants in a system | strain have stopped, the steam turbine of the combined cycle power plant to start cannot be preheated, and there exists a possibility that startup may require time.

  The present invention has been made in view of the above circumstances, and provides a power generation system that can start up in a short time and flexibly cope with output fluctuations of a renewable energy power plant even if there is no other steam turbine power plant in operation. The purpose is to do.

  To achieve the above object, a power generation system according to the present invention includes a heat source device that generates a high-temperature medium by heating a low-temperature medium with a heat-source medium, a steam generator that generates steam by heat exchange with the high-temperature medium, and A steam turbine power plant comprising a steam turbine driven by steam, a supply source for supplying a heat medium generated using energy generated outside the steam turbine power plant, at least one of the steam turbine and the steam generator A preheating device attached to one side, and a preheating line connecting the supply source and the preheating device are provided.

  ADVANTAGE OF THE INVENTION According to this invention, even if there is no other steam turbine power plant in operation, the power generation system which can be started in a short time and can respond flexibly to the output fluctuation of a renewable energy power plant can be provided.

1 is a schematic configuration diagram of a power generation system according to a first embodiment of the present invention. It is a figure for demonstrating the prediction calculation method by an electric power demand prediction apparatus. It is a flowchart which shows the procedure of the prediction calculation by an electric power demand prediction apparatus. It is a schematic block diagram of the electric power generation system which concerns on 2nd Embodiment of this invention. It is a schematic block diagram of the electric power generation system which concerns on 3rd Embodiment of this invention. It is a schematic block diagram of the electric power generation system which concerns on 4th Embodiment of this invention. It is a schematic block diagram of the electric power generation system which concerns on 5th Embodiment of this invention. It is a figure for demonstrating the prediction calculation method by an electric power demand prediction apparatus. It is a schematic block diagram of the electric power generation system which concerns on 6th Embodiment of this invention.

<First Embodiment>
(Constitution)
1. Power Generation System FIG. 1 is a schematic configuration diagram of a power generation system according to the present embodiment.

  As shown in FIG. 1, the power generation system 100 includes a steam turbine power plant 200, a heat medium supply system 300, and a preheating system 400.

2. Steam Turbine Power Plant A steam turbine power plant 200 includes a heat source device 1, a steam generator 2, a steam turbine 3, a generator 4, a heat source medium amount adjusting device 14, a steam control valve 15, and a steam turbine start control device 21. Yes. In this embodiment, a case where the heat source device 1 is a gas turbine (that is, a case where the steam turbine power plant 200 is a combined cycle power plant) will be described as an example.

  The heat source device 1 heats the low-temperature medium 6 (air, etc.) using the amount of heat held in the heat-source medium 5 (for example, gas fuel containing hydrogen-containing fuel or the like, liquid fuel) to generate the high-temperature medium 7 (gas turbine exhaust gas). Generated and supplied to the steam generator 2. The steam generator 2 (exhaust heat recovery boiler) includes a heat exchanger therein, and generates steam 8 by heating the feed water by heat exchange with the retained heat of the high-temperature medium 7 generated by the heat source device 1. The steam turbine 3 is driven by the steam 8 generated by the steam generator 2. The steam turbine 3 is provided with a thermometer 13. The thermometer 13 measures the metal temperature of the casing of the steam turbine 3 and the like. The generator 4 is coaxially connected to the steam turbine 3 and converts the rotational output of the steam turbine 3 into electric power. The electric power of the generator 4 is supplied to the electric power system 22.

  The heat source medium amount adjusting device 14 (fuel adjustment valve) is provided in the supply path of the heat source medium 5 to the heat source device 1. The heat source medium amount adjusting device 14 adjusts the flow rate of the heat source medium 5 supplied to the heat source device 1 to operate the retained heat amount of the high temperature medium 7 generated by the heat source device 1. A flow meter 11 is provided on the downstream side in the flow direction of the heat source medium 5 with respect to the heat source medium amount adjusting device 14 in the supply path of the heat source medium 5. The flow meter 11 measures the flow rate of the heat source medium 5 supplied to the heat source device 1. The steam control valve 15 is provided in a steam pipe connecting the steam generator 2 and the steam turbine 3. The steam control valve 15 adjusts the flow rate of the steam 8 supplied to the steam turbine 3. A pressure gauge 12 is provided downstream of the steam control valve 15 of the steam pipe in the flow direction of the steam 8 (steam turbine 3 side). The pressure gauge 12 measures the pressure of the steam 8 flowing through the steam pipe. The heat source medium amount adjusting device 14 and the steam control valve 15 function as an adjusting device that adjusts the power generation output amount of the steam turbine power plant 200.

  The steam turbine activation control device 21 inputs a plant state quantity of the steam turbine power plant 200 and outputs a command value for controlling the steam turbine power plant 200 based on the input plant state quantity. Examples of the input value of the plant state quantity input to the steam turbine activation control device 21 include various measured values indicating the state quantities such as components, steam temperature, pressure, and flow rate of the steam turbine power plant 200. In the present embodiment, the steam turbine activation control device 21 inputs the measurement values 16 of the flow meter 11, the pressure gauge 12 and the thermometer 13 as input values of the plant state quantity, and the heat source medium amount adjustment device as the operation amount command value 17. 14 and the steam adjustment command value for the steam control valve 15 are output.

3. Heat Medium Supply System The heat medium supply system 300 generates a heat medium using energy generated outside the steam turbine power plant 200 and supplies the heat medium to the preheating system 400. The heat medium supply system 300 includes a renewable energy power plant 500 (a solar power plant in this embodiment).

  The renewable energy power plant 500 includes a renewable energy intake device 18, a renewable energy steam generator 19, a renewable energy steam turbine 20, and a renewable energy generator 23.

  The renewable energy capture device 18 includes a heat collector (not shown) and a heat collection medium (for example, a liquid such as oil or water, or a salt). The renewable energy take-in device 18 supplies the renewable energy (solar heat) taken in via the heat collector to the heat collection medium to generate a heat medium (not shown). Supply. That is, in this embodiment, the renewable energy capture device 18 functions as a supply source that supplies a heat medium generated using renewable energy. The steam generator 19 for renewable energy has a heat exchanger inside, and heats feed water by heat exchange with the retained heat of the heat medium to generate steam. The renewable energy steam turbine 20 is driven by steam generated by the renewable energy steam generator 19. The renewable energy generator 23 is coaxially connected to the renewable energy steam turbine 20 and converts the rotational output of the renewable energy steam turbine 20 into electric power. The electric power of the renewable energy generator 23 is supplied to the electric power system 22.

4). Preheating system The preheating system 400 includes a pump 9, a power demand prediction device 24, a steam turbine heat control device 25, a steam turbine preheating adjustment valve 26, transfer pipes 28 and 29, and a casing preheating pipe 32.

  A transfer pipe (first transfer pipe) 28 connects the renewable energy intake device 18 of the renewable energy power plant 500 and the pump 9, and a transfer pipe (second transfer pipe) 29 connects the pump 9 and the casing preheating pipe 32. Is connected. The first and second transfer pipes 28 and 29 are pipes that are separate from the pipes that supply a part of the heat medium generated by the renewable energy intake device 18 to the steam generator 19 for the renewable energy, and can be regenerated. The heat medium generated by the energy capturing device 18 is supplied to the casing preheating pipe 32. That is, in the present embodiment, the first and second transfer pipes 28 and 29 function as a preheating line that connects the renewable energy intake device 18 and the casing preheating pipe 32.

  The pump 9 has a suction port connected to the renewable energy intake device 18 via the first transfer pipe 28, and a discharge port connected to the casing preheating pipe 32 via the second transfer pipe 29. The pump 9 is driven by, for example, a motor (not shown). When the pump 9 is driven, the pump 9 sucks the heat medium generated by the renewable energy capturing device 18 through the first transfer pipe 28, discharges it to the second transfer pipe 29, and supplies it to the casing preheating pipe 32. To do.

  The steam turbine preheating adjustment valve (regulation valve) 26 is provided in the second transfer pipe 29. The steam turbine preheating adjustment valve 26 is electrically connected to the steam turbine heat control device 25 and switches between opening and closing of the second transfer pipe 29 in response to signals 27A and 27B from the steam turbine heat control device 25. Specifically, when the signal (opening signal) 27 </ b> A from the steam turbine heat control device 25 is input, the steam turbine preheating adjustment valve 26 opens the second transfer pipe 29, and the signal from the steam turbine heat control device 25 ( When the cutoff signal 27B is input, the second transfer pipe 29 is shut off.

  The casing preheating pipe 32 is a heat exchanger attached to the outer wall surface of the casing of the steam turbine 3. The casing preheating pipe 32 heats the casing of the steam turbine 3 using the heat medium supplied from the renewable energy intake device 18. That is, in this embodiment, the casing preheating pipe 32 functions as a preheating device that heats the casing of the steam turbine 3.

  The electric power demand prediction device (prediction unit) 24 stores the results and scheduled data regarding the stop date / time, the start / start date / time and the start / end date / time of the steam turbine 3 in a storage unit (not shown). The power demand prediction device 24 uses the actual data and scheduled data regarding the stop date / time, start start date / time and start completion date / time of the steam turbine 3 stored in the storage unit, and the next casing preheating start date / time and steam turbine start start date / time (casing). (Preheating completion date and time) is predicted and output to the steam turbine heat control device 25. The prediction calculation method of the power demand prediction device 24 will be described later. In the present embodiment, the casing preheating start date / time to be calculated is calculated by going backward from the date / time when the start of the steam turbine 3 is completed (steam turbine start completion date / time), or the date and time before the start time. A date and time that is earlier than the current date and time.

  The steam turbine heat control device 25 inputs the casing preheating start date and time and the steam turbine start start date and time which are predicted and calculated by the power demand prediction device 24. The steam turbine heat control device 25 outputs a signal 27A to the steam turbine preheating adjustment valve 26 at the input casing preheating start date and time to open the second transfer pipe 29. On the other hand, the steam turbine heat control device 25 outputs a signal 27B to the steam turbine preheating adjustment valve 26 at the input date and time of starting the steam turbine, and shuts off the second transfer pipe 29 and sends a signal ( A start signal 27C is output to start the steam turbine 3.

  FIG. 2 is a diagram for explaining a prediction calculation method by the power demand prediction device 24. The horizontal axis in FIG. 2 indicates time, and the origin is the current time. Note that FIG. 2 illustrates a case where it is predicted that the power generation capacity of the renewable energy power plant 500 will decrease and the power shortage will occur while the power demand will increase for a certain period in the future.

  A power demand prediction line 51 indicates a predicted value of power demand ahead of a certain period from the present. The renewable energy power generation capacity prediction line 52 indicates a predicted value of the power generation capacity of the renewable energy power plant 500 (the amount of power that can be output by the renewable energy power plant 500). The power demand prediction line 51 and the renewable energy power generation capacity prediction line 52 are predicted by the power demand prediction device 24 using the seasons, time zone changes, and past performance as parameters. In the present embodiment, the power generation capacity of the renewable energy power plant 500 includes the amount of power obtained using surplus energy stored by some means in the renewable energy power plant 500.

  A casing temperature prediction line 53 indicates a predicted value of the temperature of the casing of the steam turbine 3. As shown in FIG. 2, the temperature of the casing of the steam turbine 3 gradually decreases toward normal temperature due to natural cooling with the elapsed time from when the steam turbine 3 stops until the preheating of the casing is started. .

  The renewable energy power generation output prediction line 54 indicates a predicted value of the power generation output of the renewable energy power plant 500 (the amount of power output from the renewable energy power plant 500 according to the power demand). For example, when the power demand exceeds the power generation capacity of the renewable energy power plant 500, the renewable energy power output becomes the renewable energy power generation capacity. On the other hand, when the power demand is lower than the power generation capacity of the renewable energy power generation plant 500 (that is, the demand power can be supplied with a power amount smaller than the renewable energy power generation capacity), the renewable energy power generation output is smaller than the renewable energy power generation capacity. . At this time, the difference between the renewable energy power generation capacity and the renewable energy power generation output is stored as a surplus energy of the renewable energy power plant 500 in a heat storage device (not shown) or the like.

  The steam turbine power plant output prediction line 55 indicates the predicted value of the power generation output of the steam turbine power plant 200 (the amount of power output from the steam turbine power plant 200).

  The total output prediction line 56 indicates the total value of the amount of power output from the renewable energy power plant 500 and the amount of power output from the steam turbine power plant 200. That is, the total output prediction line 56 is obtained by adding the renewable energy power generation output prediction line 54 and the steam turbine power plant output prediction line 55 together.

  Next, a prediction calculation method by the power demand prediction device 24 will be described.

  For example, as at present in FIG. 2, when the renewable energy power plant 500 is operating and the steam turbine power plant 200 is stopped, the power demand prediction device 24 uses the power demand prediction line 51 illustrated in FIG. 2. Assume that the renewable energy power generation capacity prediction line 52 and the total output prediction line 56 are predicted. In this case, the power demand prediction device 24 predicts that the power demand prediction line 51 and the renewable energy power generation capacity prediction line 52 intersect with each other (time A in FIG. 2), resulting in a power shortage, and the steam turbine power plant. It is determined that 200 needs to be operated.

  By the way, when the steam turbine 3 is started in the hot mode, the curve indicating the power generation output of the steam turbine power plant 200 and the time from the start of the start of the steam turbine 3 to the completion of the start are constant. Can be stored in advance in the unit. Therefore, the power demand prediction device 24 is based on the power demand prediction line 51, the renewable energy power generation capacity prediction line 52, the curve indicating the power generation output of the steam turbine power plant 200, and the time from the start of the steam turbine 3 to the completion of the start. Then, the steam turbine startup start date and time is predicted and calculated so that the total power output of the power generation output of the steam turbine power plant 200 and the power generation output of the renewable energy power plant 500 does not fall below the power demand at time A.

  On the other hand, when preheating the casing of the steam turbine 3, the time from the start of preheating to the completion of preheating when the casing temperature reaches the hot mode (preheating time), the total amount of energy required for preheating, and the casing temperature prediction line 53 are shown in FIG. It can be represented by a function according to the temperature of the casing at the time (that is, a function including the temperature of the casing at the time of starting preheating as a parameter). The casing temperature at the start of preheating can be expressed by a function corresponding to the time from the steam turbine stop date and time to the start of preheating (that is, a function including the time from the steam turbine stop date and time to the start of preheating as a parameter). Therefore, the power demand prediction device 24 calculates the temporary casing preheating start date and the total energy amount necessary for preheating using the above-described functions based on the steam turbine stop date and time and the steam turbine start start date and time.

  And the electric power demand prediction apparatus 24 calculates the integrated value of the surplus energy from a temporary casing preheating start date and time to a steam turbine starting start date and time, and a temporary casing is set so that surplus energy may exceed the total energy amount required for preheating. Advance the preheating start date and time (ie, correct to the current side). If the provisional casing preheating start date / time is advanced, the temperature of the casing at the start of preheating changes as indicated by the casing temperature prediction line 53, so the total amount of energy required for preheating also changes. The power demand prediction device 24 repeats the calculation of the integrated value of surplus energy from the temporary casing preheating start date and time to the steam turbine start start date and time while moving forward the temporary casing preheating start date and time, so that the optimum casing preheating start date and time (casing Predicting calculation of the optimal value of preheating start date and time. In the present embodiment, the optimal casing preheating start date and time is the difference between the surplus energy and the total energy required for preheating without the surplus energy of the renewable energy power plant 500 falling below the total energy required for preheating. Says the date and time when becomes the minimum.

  In the above description, as shown in FIG. 2, it is assumed that the steam turbine 3 is stopped from the current date and time until the casing preheating start date and time, and the power demand prediction device 24 uses the power demand prediction line 51 and the renewable energy power generation. The case where the steam turbine start start date and time is predicted and calculated based on the difference from the capacity prediction line 52 has been described. However, for example, when the steam turbine 3 is stopped between the present time and the casing preheating start date and time, the power demand prediction device 24 determines the steam based on the difference between the power demand prediction line 51 and the total output prediction line 56. A turbine start start date and time (that is, a restart start date and time of the steam turbine 3) is predicted and calculated.

(Operation)
FIG. 3 is a flowchart showing the procedure of the prediction calculation by the power demand prediction device 24.

  As illustrated in FIG. 3, the power demand prediction device 24 clears and initializes past prediction calculation data stored in the storage unit before starting the prediction calculation (step S <b> 1).

  Subsequently, the power demand prediction device 24 needs to predict the power demand prediction line 51, the renewable energy power generation capacity prediction line 52, and the total output prediction line 56 (Step S2), and operate the steam turbine power plant 200. Whether or not (step S3). Specifically, when it is determined that the steam turbine power plant 200 needs to be operated (Yes), the power demand prediction device 24 moves the procedure from step S3 to step S4. Conversely, when it is determined that it is not necessary to operate the steam turbine power plant 200 (No), the power demand prediction device 24 ends the prediction calculation procedure and clears the prediction calculation data.

  When it is determined in step S3 that the steam turbine power plant 200 needs to be operated, the power demand prediction device 24 predicts and calculates the steam turbine activation start date and time (step S4).

  Next, the power demand prediction device 24 determines whether or not it is necessary to preheat the steam turbine 3 based on the steam turbine stop date and time and the steam turbine start date and time (step S5). Specifically, the power demand prediction device 24 predicts and calculates the casing temperature Tc at the steam turbine start start date and time based on the time from the steam turbine stop date and time to the steam turbine start start date and time. When the casing temperature Tc at the start date and time of starting the steam turbine is lower than the set temperature Th that satisfies the condition of the hot mode (Yes), the power demand prediction device 24 determines that the steam turbine 3 needs to be preheated, and step S5 To step S6. On the other hand, when the casing temperature Tc is equal to or higher than the set temperature Th (No), the power demand prediction device 24 determines that it is not necessary to preheat the steam turbine 3, ends the prediction calculation procedure, and clears the prediction calculation data. To do.

  When it is determined in step S5 that the steam turbine 3 needs to be preheated, the power demand prediction device 24 determines the provisional casing preheat start date and time and the total number required for preheating based on the steam turbine stop date and time and the steam turbine start date and time. An energy amount is predicted and calculated (step S6).

  Subsequently, the power demand prediction device 24 predicts and calculates the optimum casing preheating start date and time (step S7).

  Subsequently, the power demand prediction device 24 outputs the optimum casing preheating start date and time and the steam turbine activation start date and time to the steam turbine heat control device 25 (step S8).

  The power demand prediction device 24 repeats the above-described operation (step S1 to step S8) at regular time intervals until the steam turbine activation start date and time. The steam turbine heat control device 25 sequentially inputs and overwrites information such as the casing preheating start date and time repeatedly output from the power demand prediction device 24 every predetermined time, and always stores the latest information.

(effect)
(1) In the power generation system 100 according to the present embodiment, a heat medium generated using energy generated outside the steam turbine power plant 200 is supplied to the casing preheating pipe 32 to preheat the steam turbine 3. Therefore, it is possible to preheat the steam turbine 3 without any other steam turbine power plant in operation, and to provide a power generation system that can start up in a short time and flexibly cope with output fluctuations of a renewable energy power plant. be able to.

  In general, in the steam turbine, when the temperature of the inflowing steam rises rapidly, the temperature distribution in the metal portion of the casing becomes non-uniform and thermal deformation may occur. Therefore, at the time of starting the steam turbine, it is necessary to control the starting speed so that the rate of increase in the temperature of the steam is equal to or less than the set value. On the other hand, in this embodiment, since the steam turbine 3 is preheated by the heat medium generated using energy generated outside the steam turbine power plant 200, the temperature of the steam 8 flowing into the steam turbine 3 rapidly increases. Even in this case, the temperature distribution in the metal portion of the casing can be prevented from becoming non-uniform and can be quickly activated.

  (2) In the power generation system 100 according to the present embodiment, the preheating start date and time is predicted and calculated based on the stop date and time and the start start date and time of the steam turbine 3, and the preheating is started at the predicted preheating start date and time. Therefore, the steam turbine 3 can be preheated according to the start date and time of the steam turbine 3.

  (3) In the power generation system 100 according to the present embodiment, a heat medium using a part of the renewable energy used in the renewable energy power plant while allocating the power generation output of the renewable energy power plant to the power demand. And the steam turbine 3 is preheated to shorten the startup time. Therefore, the power generation output of the renewable energy power plant can be utilized to the maximum with respect to the power demand, and the system power can be stabilized.

  Generally, a steam turbine power plant such as a combined cycle power plant is designed so that energy efficiency is maximized at a rated output for power generation. Therefore, the fossil fuel utilization efficiency decreases as preheating and start-up time that are less than the rated output become longer (that is, the supply amount of fossil fuel increases relative to the amount of power generation). In contrast, in the present embodiment, as described above, the steam turbine 3 is preheated using renewable energy, so that the fossil fuel is used only for short-time hot mode start-up and rated power generation. And the utilization efficiency of fossil fuel can be improved.

Second Embodiment
(Constitution)
FIG. 4 is a schematic configuration diagram of the power generation system according to the present embodiment. In FIG. 4, parts that are the same as in the first embodiment are given the same symbols, and descriptions thereof are omitted as appropriate.
The power generation system 101 according to the present embodiment is different from the power generation system 100 according to the first embodiment in that a heat medium storage system 601 is further provided. Other configurations are the same as those of the first embodiment.

  As shown in FIG. 4, the heat medium storage system 601 includes a heat medium storage device 34, a heat medium storage amount control device 35, a pump 36, and a heat medium storage amount adjustment device 37.

  In the present embodiment, the first transfer pipe 28 includes first, second, and third supply pipes 28A, 28B, and 28C. The first supply pipe 28A connects the renewable energy capture device 18 and the pump 36, the second supply pipe 28B connects the pump 36 and the heat medium storage device 34, and the third supply pipe 28C connects to the heat medium storage device 34. A pump 9 is connected.

  The pump 36 has a suction port connected to the first supply pipe 28A and a discharge port connected to the second supply pipe 28B. The pump 36 is driven by, for example, a motor (not shown). When the pump 36 is driven, the pump 36 sucks the heat medium generated by the renewable energy capturing device 18 through the first supply pipe 28A, and discharges the heat medium to the second supply pipe 28B to the heat medium storage device 34. Supply.

  The heat medium storage device (in this embodiment, a heat storage tank) 34 includes a heat exchanger, and heats the stored heat medium by heat exchange with the heat medium supplied from the renewable energy capture device 18. A secondary heat medium (not shown) is generated and accumulated, and supplied to the casing preheating pipe 32 via the second and third supply pipes 28B and 28C.

  The heat medium accumulation amount adjusting device (heat medium amount adjusting valve) 37 is provided in the middle of the second supply pipe 28B. The heat medium accumulation amount adjusting device 37 is electrically connected to the heat medium accumulation amount control device 35, and the opening degree is adjusted according to a signal (drive signal) 27D from the heat medium accumulation amount control device 35. That is, the heat medium accumulation amount adjusting device 37 receives the signal 27D from the heat medium accumulation amount control device 35 and adjusts the flow rate of the heat medium supplied from the renewable energy capturing device 18 to the heat medium accumulation device 34. .

  In the present embodiment, the power demand prediction device 24 includes the remaining amount of the secondary heat medium (heat medium remaining amount) in the heat medium storage device 34 in addition to the next casing preheating start date and time and the steam turbine activation start date and time, Based on the power demand prediction line 51, the renewable energy power generation capacity prediction line 52, and the next casing preheating start date and time, the heat medium accumulation start date and time is predicted and calculated and output to the heat medium accumulation amount control device 35. In the present embodiment, the heat medium accumulation start date and time for the predictive calculation is calculated based on the present time as the base point from the date and time when the start of the steam turbine 3 should be completed, and the preheat time, the start time, and the heat medium remaining time of the heat medium accumulation device 34 From the state where the amount is 0 (that is, the state where the secondary heat medium is not stored in the heat medium storage device 34) to the state where the remaining amount of the heat medium is satisfied (that is, the secondary heat medium is present in the heat medium storage device 34). This refers to the date and time that is earlier than the current date and time, or the date and time that is earlier than the required time until the maximum amount is accumulated).

  The heat medium accumulation amount control device 35 inputs the heat medium accumulation start date and time calculated by the power demand prediction device 24. The heat medium accumulation amount control device 35 outputs a signal 27D to the heat medium accumulation amount adjustment device 37 at the input heat medium accumulation start date and time, and adjusts the opening degree of the heat medium accumulation amount adjustment device 37. A heat medium is supplied to 34.

(effect)
In the present embodiment, in addition to the same effects as those of the first embodiment, the following effects can be obtained.

  In the present embodiment, since the heat medium is supplied to the heat medium storage device 34 at the heat medium storage start date and time calculated by the power demand prediction device 24 and generation and storage of the secondary heat medium are started, it is necessary for preheating. Total energy can be secured in advance. Therefore, for example, even when the preheating time is prolonged and the actual surplus power fluctuates from the prediction, the total energy necessary for preheating is ensured by the start date and time of starting the steam turbine, and the steam turbine 3 is sufficiently preheated. be able to.

<Third Embodiment>
(Constitution)
FIG. 5 is a schematic configuration diagram of the power generation system according to the present embodiment. In FIG. 5, parts that are the same as in the second embodiment are given the same symbols, and descriptions thereof are omitted as appropriate.

  In the power generation system 102 according to the present embodiment, the preheating system 402 uses the heating wire 41 instead of the casing preheating pipe 32, the electric wires 42, 44, and 45 instead of the first and second transfer pipes 28 and 29, and the steam turbine preheating adjustment. It differs from the power generation system 101 according to the second embodiment in that a switch 39 is provided instead of the valve 26 and the heat medium storage system 602 does not include the pump 36. Other configurations are the same as those of the second embodiment.

  The electric wire 42 connects the renewable energy generator 23 and the heat medium storage device 34, and supplies a part of surplus power generated by the renewable energy generator 23 to the heat medium storage device 34 as a heat medium. . That is, in this embodiment, the generator 23 for renewable energy functions as a supply source for supplying a heat medium generated by using renewable energy. The electric wire 44 connects the heat medium storage device 34 and the switch 39, and the electric wire 45 connects the switch 39 and the heating wire 41. The electric wires 44 and 45 supply surplus power stored in the heat medium storage device 34 to the heating wire 41. That is, in this embodiment, the electric wires 42, 44, 45 function as a preheating line that connects the renewable energy generator 23 and the heating wire 41.

  The heating wire 41 heats the casing of the steam turbine 3 using surplus power supplied from the heat medium storage device 34 via the electric wires 44 and 45. That is, in the present embodiment, the heating wire 41 functions as a preheating device that heats the casing of the steam turbine 3.

  The switch 39 is electrically connected to the steam turbine heat control device 25, and is turned on (position where the electric wire 44 and the electric wire 45 are connected) and cut position according to signals 27A and 27B from the steam turbine heat control device 25. (Position where the connection between the electric wire 44 and the electric wire 45 is cut) is switched. Specifically, when the signal 27A from the steam turbine heat control device 25 is input, the switch 39 switches from the cut position to the turn position to connect the electric wire 44 and the electric wire 45 and the signal from the steam turbine heat control device 25. When 27B is input, the connection position is switched from the entry position to the cut position, and the connection between the wires 44 and 45 is cut.

  The heat medium storage device (storage battery in the present embodiment) 34 stores surplus power supplied from the renewable energy generator 23 via the electric wire 42.

  In the present embodiment, the configuration in which the power generation system 102 includes the heat medium storage device 34 and the heat medium storage amount adjustment device 37 is exemplified, but the heat medium storage device 34 and the heat medium storage amount adjustment device 37 are not included. Also good. In that case, a part of the surplus power generated by the renewable energy generator 23 is directly supplied to the heating wire 41 via the electric wires 42, 44, 45. In addition, the power demand prediction device 24 predicts and calculates the temporary casing preheating start date and time according to the procedure described in the first embodiment, and then optimizes the power demand prediction device 24 based on the renewable energy power generation output prediction line 54 and the power demand prediction line 51. The casing preheating start date is predicted and calculated.

(effect)
In this embodiment, in addition to the same effects as those of the second embodiment, the following effects can be obtained.

  In the present embodiment, a part of surplus power generated by the renewable energy generator 23 is supplied to the heating wire 41 to heat the casing of the steam turbine 3. Therefore, a power generation plant other than heat utilization such as a solar power generation plant, a wind power generation plant, or a hydroelectric power generation plant can be adopted as the renewable energy power generation plant 500.

  Moreover, in this embodiment, since the electric wires 42, 44, and 45 and the heating wire 41 are provided instead of the casing preheating pipe 32 instead of the first and second transfer pipes 28 and 29, compared to the above-described embodiments. The number of pipes can be reduced. Therefore, maintainability of the power generation system can be improved. Furthermore, as described above, since the surplus power is used as the heat medium, the supply amount to the preheating device can be easily controlled as compared with the case where liquid, solid, or the like is used as the heat medium.

<Fourth embodiment>
(Constitution)
FIG. 6 is a schematic configuration diagram of the power generation system according to the present embodiment. In FIG. 6, the same symbols are given to parts equivalent to those in the third embodiment, and the description is omitted as appropriate.

  The power generation system 103 according to the present embodiment is different from the power generation system 102 according to the third embodiment in that the preheating system 403 includes an energy conversion system 703 and includes a casing preheating pipe 32 instead of the heating wire 41. Other configurations are the same as those of the third embodiment.

  The energy conversion system 703 includes an energy conversion device 43, a pump 47, a heat medium supply device 48, first and second and third pipes 49, 50 and 57, and an electric wire 58.

  The first pipe 49 connects the heat medium supply device 48 and the pump 47, the second pipe 50 connects the pump 47 and the heat exchanger 46 of the energy conversion device 43, and the third pipe 57 connects the heat exchanger 46 and the casing preheating. A tube 32 is connected.

  The pump 47 has a suction port connected to the first pipe 49 and a discharge port connected to the second pipe 50. The pump 47 is driven by, for example, a motor (not shown). When the pump 47 is driven, the pump 47 sucks the heat medium through the first pipe 49, discharges it to the second pipe 50, and supplies it to the heat exchanger 46.

  The energy conversion device (heat pump) 43 includes a heat exchanger 46, and uses the surplus power supplied from the heat medium storage device 34 via the electric wire 44 to convert the heat medium supplied from the heat medium supply device 48. A secondary heat medium (not shown) is generated by heating and supplied to the casing preheating pipe 32 via the third pipe 57. That is, in this embodiment, the electric wire 44, the energy conversion device 43, and the third pipe 57 function as a preheating line that connects the renewable energy generator 23 and the casing preheating pipe 32.

  The electric wire 58 connects the energy conversion device 43 and the heat medium storage device 34. The electric wire 58 is supplied from the heat medium storage device 34 to the energy conversion device 43, and returns surplus power that has heated the heat medium to the heat medium storage device 34.

  Note that, similarly to the third embodiment, in this embodiment, the power generation system 103 may not include the heat medium storage device 34 and the heat medium storage amount adjustment device 37. When the power generation system 103 does not include the heat medium storage device 34 and the heat medium storage amount adjustment device 37, the prediction calculation procedure performed by the power demand prediction device 24 is executed according to the same procedure as in the first embodiment. If it is, the same procedure as in the second embodiment is executed.

  Even when configured as in the present embodiment, the same effects as in the third embodiment can be obtained.

<Fifth Embodiment>
(Constitution)
FIG. 7 is a schematic configuration diagram of the power generation system according to the present embodiment. In FIG. 7, parts that are the same as in the first embodiment are given the same symbols, and descriptions thereof are omitted as appropriate.

  The power generation system 104 according to the present embodiment is different from the power generation system 100 according to the first embodiment in that the preheating system 404 includes a drum preheating pipe 61, a drum preheating adjustment valve 62, and a transfer pipe 63. Other configurations are the same as those of the first embodiment.

  The drum preheating pipe 61 is a heat exchanger attached to the outer wall surface of the drum of the steam generator 2. The drum preheating pipe 61 heats the drum of the steam generating device 2 using the heat medium supplied from the renewable energy capturing device 18. That is, in this embodiment, the casing preheating pipe 32 functions as a preheating apparatus that heats the casing of the steam turbine 3, and the drum preheating pipe 61 functions as a preheating apparatus that heats the drum of the steam generation apparatus 2.

  The transfer pipe (third transfer pipe) 63 branches on the upstream side in the flow direction of the heat medium with respect to the steam turbine preheating adjustment valve 26 of the second transfer pipe 29 and is connected to the drum preheating pipe 61 of the steam generator 2. ing. That is, the third transfer pipe 63 connects the renewable energy intake device 18 and the drum preheating pipe 61.

  The drum preheating adjustment valve 62 is provided in the drum preheating pipe 61. The drum preheating adjustment valve 62 is electrically connected to the steam turbine heat control device 25 and switches between opening and closing of the third transfer pipe 63 in response to signals 27E and 27F from the steam turbine heat control device 25. Specifically, when the signal (opening signal) 27E from the steam turbine heat control device 25 is input, the drum preheating adjustment valve 62 opens the third transfer pipe 63 and the signal (blocking) from the steam turbine heat control device 25. When the signal 27F is input, the third transfer pipe 63 is shut off. In other words, in the present embodiment, the steam turbine heat control device 25 outputs signals 27A and 27B to the steam turbine preheating adjustment valve 26 and outputs signals 27E and 27F to the drum preheating adjustment valve 62.

  In the present embodiment, the power demand prediction device 24 predicts and calculates the drum preheating start date and time in addition to the casing preheating start date and time and the steam turbine activation start date and time.

(Operation)
FIG. 8 is a diagram for explaining a prediction calculation method by the power demand prediction device 24. The horizontal axis in FIG. 8 indicates time, and the origin is the current time.

  The drum temperature prediction line 71 indicates a predicted value of the drum temperature of the steam generator 2. As shown in FIG. 8, the temperature of the drum of the steam generator 2 gradually increases toward the normal temperature by natural cooling with the elapsed time after the supply of the high-temperature medium 7 is stopped until the preheating of the drum is started. To drop. The steam turbine power plant output prediction line 55 is the same as that shown in FIG.

  After the heat source device 1 is ignited to generate the hot medium 7, the amount of the hot medium 7 generated is increased as quickly as possible, and the generated amount of the hot medium 7 is set to the rated state at the time of starting the steam turbine. Under such conditions, the time from the completion of drum preheating to the start of steam turbine startup is constant. Therefore, the power demand prediction device 24 predicts and calculates the drum preheating completion date and time based on the power demand prediction line 51, the renewable energy power generation capacity prediction line 52, and the steam turbine power plant output prediction line 55 shown in FIG.

  On the other hand, the time from the start of drum preheating to the completion of preheating (drum preheating time), the total amount of energy required for preheating, and the drum temperature prediction line 71 are functions corresponding to the drum temperature at the start of drum preheating (that is, preheating start). It can be expressed as a function using the drum temperature at the time as a parameter. The drum temperature at the start of drum preheating is a function corresponding to the time from the supply stop date / time of the high temperature medium 7 to the drum preheat start date / time (ie, the time from the supply stop date / time of the high temperature medium 7 to the drum preheat start date / time Function included as a parameter). Accordingly, the power demand prediction device 24 uses the above-described functions to calculate the temporary drum preheating start date (not shown) and drum preheating based on the supply stop date and time of the hot medium 7 and the predicted and calculated drum preheating completion date and time. Calculate the total amount of energy required.

  Then, the power demand prediction device 24 predicts and calculates the temporary casing preheating start date and time and the temporary drum preheating start date and time by the same method as in the first embodiment. Next, the power demand prediction device 24 sets the earlier (closer to the present) date / time (hereinafter, date / time a) of the temporary casing preheating start date / time and the temporary drum preheating start date / time, and the casing preheating completion date / time and drum preheating completion date / time. Of these, the later date (away from the present) is calculated (hereinafter, date b). Subsequently, the power demand prediction device 24 calculates an integrated value (hereinafter, energy E) of surplus energy from the date and time a to the date and time b, and the energy E is necessary for preheating the total amount of energy required for preheating the casing and the drum. The temporary casing preheating start date and time and the temporary drum preheating start date and time are advanced so as to exceed the total amount of the total energy. If the provisional casing preheating start date and provisional drum preheating start date are advanced, the casing and drum temperatures at the start of preheating change as indicated by the casing temperature prediction line 53 and the drum temperature prediction line 71. The total amount of total energy and the total amount of energy required to preheat the drum will also vary. Subsequently, the power demand prediction device 24 repeats the calculation of the energy E while moving forward the provisional casing preheating start date and time and the provisional drum preheating start date and time, so that the optimum casing preheating start date and the optimum drum preheating start date and time (drum Predicting calculation of the optimal value of preheating start date and time. Then, the power demand prediction device 24 outputs the casing preheating start date and time, the steam turbine start start date and time, the drum preheating start date and time, and the drum preheating completion date and time to the steam turbine heat control device 25.

  The steam turbine heat control device 25 inputs the casing preheating start date and time, the steam turbine start start date and time, the drum preheating start date and time, and the drum preheating completion date and time from the power demand prediction device 24. The steam turbine heat control device 25 outputs a signal 27E to the drum preheating adjustment valve 62 at the input drum preheating start date and time to open the third transfer pipe 63. On the other hand, the steam turbine heat control device 25 outputs the signal 27F to the drum preheating adjustment valve 62 at the input drum preheating completion date and time, thereby blocking the third transfer pipe 63. Then, the steam turbine heat control device 25 outputs a signal 27C to the steam turbine start control device 21 at the input steam turbine start start date and time to start the steam turbine 3.

  In the present embodiment, the power demand prediction device 24 repeats the above-described operation at regular intervals until the steam turbine start start date and time. Further, the steam turbine heat control device 25 sequentially inputs information on the casing preheating start date and time, the steam turbine start start date and time, the drum preheating start date and time, and the drum preheating completion date and time that are repeatedly output from the power demand prediction device 24 at regular intervals. Overwriting and always storing the latest information.

(effect)
In the present embodiment, in addition to the same effects as those of the first embodiment, the following effects can be obtained.

  In this embodiment, since the drum of the steam generator 2 can be preheated using the heat medium supplied from the renewable energy capture device 18, combined cycle power generation can be performed more quickly than in the first embodiment. The plant can be started.

  In general, in the steam generator, when the temperature of the inflowing high-temperature medium rises rapidly, the temperature distribution in the metal portion of the drum becomes non-uniform and thermal deformation may occur. Therefore, at the time of starting the steam generator, it is necessary to suppress the starting speed so that the temperature increase rate of the high-temperature medium is not more than a specified value. On the other hand, in this embodiment, since the steam generator 2 is preheated by the heat medium generated using energy generated outside the steam turbine power plant 200, the high temperature medium 7 flowing into the steam generator 2 is not heated. Even when the temperature rises rapidly, the temperature distribution in the metal portion of the drum can be prevented from becoming non-uniform and can be started quickly.

<Sixth Embodiment>
(Constitution)
FIG. 9 is a schematic configuration diagram of a power generation system according to the present embodiment. In FIG. 9, parts that are the same as in the first embodiment are given the same symbols, and descriptions thereof are omitted as appropriate.

  The power generation system 105 according to the present embodiment is the first embodiment in that the preheating system 405 includes a transfer pipe 59 instead of the first and second transfer pipes 28 and 29, and does not include the pump 9 and the casing preheat pipe 32. Different from the power generation system 100 according to FIG. Other configurations are the same as those of the first embodiment.

  The transfer pipe (fourth transfer pipe) 59 is connected to the steam generator 19 for renewable energy and the steam pipe connecting the steam generator 2 and the steam turbine 3, and is generated in the steam generator 19 for renewable energy. A part of the steam is supplied as a heat medium to the steam turbine 3 through the steam pipe. That is, in this embodiment, the steam generator 19 for renewable energy functions as a supply source for supplying a heat medium generated by using renewable energy. The steam supplied to the fourth transfer pipe 59 is a part of the surplus obtained by subtracting the amount used for the power generation output of the renewable energy power plant 500 from the steam generated by the steam generator 19 for renewable energy. In addition, as described above, when the steam turbine is started, there is a possibility that the turbine rotor that is a rotating body and the casing that is a stationary body may come into contact with each other and be damaged. Therefore, in this embodiment, the flow rate of the steam supplied from the fourth transfer pipe 59 to the steam pipe is set lower than the constraint condition.

  In addition, the heat medium storage device 34 and the energy conversion device 43 of the fourth embodiment are added to the power generation system 105 according to the present embodiment, and steam supplied from the heat medium storage device 34 via the fourth transfer pipe 59 is used. Then, the heat medium (steam) supplied from the heat medium supply device 48 in the energy conversion device 43 may be heated and supplied to the casing preheating pipe 32. In this case, since it is not necessary to extend the 4th transfer pipe 59 to supply piping, the 4th transfer pipe 59 can be shortened compared with this embodiment, and management of an electric power generation system becomes easy.

(effect)
In the present embodiment, in addition to the same effects as those of the first embodiment, the following effects can be obtained.

  In this embodiment, since it is not necessary to provide the casing preheating pipe 32 etc., the increase in manufacturing cost can be suppressed by that much.

<Others>
The present invention is not limited to the above-described embodiments, and includes various modifications. For example, each of the above-described embodiments has been described in detail for easy understanding of the present invention, and is not necessarily limited to one having all the configurations described. For example, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment.

  In the above-described embodiments, the configuration in which only the steam turbine power plant 200 and the renewable energy power plant 500 are connected to the power system 22 has been described. However, the essential effect of the present invention is to provide a power generation system that can start up in a short time and flexibly cope with output fluctuations of a renewable energy power plant even if there is no other steam turbine power plant in operation. As long as this essential effect is obtained, the configuration is not necessarily limited to the above. For example, if the nuclear power plant, the cogeneration plant using fossil fuel, or the like is connected to the power system 22 instead of the renewable energy power plant 500, the above-described essential effect can be obtained.

  Moreover, in each embodiment mentioned above, the case where a solar thermal power generation plant was applied as the renewable energy power generation plant 500 was demonstrated. However, as long as the above-described essential effects of the present invention are obtained, the solar power generation plant is not necessarily required. For example, a geothermal power plant, a waste combustion power plant, a biomass combustion power plant, or the like can be applied.

DESCRIPTION OF SYMBOLS 1 Heat source apparatus 2 Steam generator 3 Steam turbine 5 Heat source medium 6 Low temperature medium 7 High temperature medium 18 Renewable energy capture device (supply source)
19 Steam generator for renewable energy (source)
23 Generator for renewable energy (supply source)
24 Electricity demand forecasting device (prediction unit)
25 Steam Turbine Heat Control Device 26 Steam Turbine Preheating Regulating Valve (Regulating Valve)
28, 29 1st and 2nd transfer pipe (preheating line)
32 Casing preheating tube (preheating device)
34 Heat medium storage device 35 Heat medium accumulation amount control device 37 Heat medium accumulation amount adjustment device 41 Heating wire (preheating device)
42, 44, 45 Electric wire (preheating line)
43 Energy Converter 61 Drum Preheating Tube (Preheating Device)
100, 101, 102, 103, 104, 105 Power generation system 200 Steam turbine power plant 500 Renewable energy power plant

Claims (8)

A heat source apparatus that generates a high temperature medium by heating a low temperature medium with a heat source medium, a steam generator that generates steam by heat exchange with the high temperature medium, and a steam turbine power plant that includes the steam turbine driven by the steam;
A supply source for supplying a heat medium generated using energy generated outside the steam turbine power plant;
A preheating device attached to at least one of the steam turbine and the steam generator;
A power generation system comprising the supply source and a preheating line connecting the preheating device. The power generation system according to claim 1,
The power generation system according to claim 1, wherein the preheating device is a casing preheating pipe attached to a casing of the steam turbine. The power generation system according to claim 1,
A regulating valve provided in the preheating line;
A prediction unit that predicts a preheating start date and time, which is a date and time when at least one of the steam turbine and the steam generating device should start preheating, based on the stop date and start date and time of the steam turbine;
A power generation system comprising: a steam turbine heat control device that inputs a preheating start date and time predicted by the prediction unit and outputs a signal to the adjustment valve at the preheating start date and time. The power generation system according to claim 3,
A power generation system comprising a renewable energy power plant, wherein the supply source generates the heat medium using a part of the renewable energy used in the renewable energy power plant. The power generation system according to claim 4,
The prediction unit predicts and calculates the accumulation start date and time of the heat medium,
A heat medium accumulation amount control device for inputting the accumulation start date and time;
A heat medium storage device that is provided in the preheating line and generates and stores a secondary heat medium using the heat medium;
A power generation system comprising: a heat medium accumulation amount adjusting device that inputs a signal from the heat medium accumulation amount control device and adjusts a flow rate of the heat medium supplied to the heat medium accumulation device. The power generation system according to claim 4,
The prediction unit predicts and calculates the accumulation start date and time of the heat medium,
A heat medium accumulation amount control device for inputting the accumulation start date and time;
A heat medium storage device that is provided in the preheating line and stores the heat medium;
A power generation system comprising: a heat medium accumulation amount adjusting device that inputs a signal from the heat medium accumulation amount control device and adjusts a flow rate of the heat medium supplied to the heat medium accumulation device. The power generation system according to claim 6,
An electric power generation system comprising an energy conversion device that generates a secondary heat medium using the heat medium. A heat source apparatus that generates a high temperature medium by heating a low temperature medium with a heat source medium, a steam generator that generates steam by heat exchange with the high temperature medium, and a steam turbine power plant that includes the steam turbine driven by the steam;
A steam pipe connecting the steam generator and the steam turbine;
A supply source for supplying a heat medium generated using energy generated outside the steam turbine power plant;
A power generation system comprising: a preheating line connecting the supply source and the steam pipe.

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