JPS6333057B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is applied to superheater mouth temperature control of a concentrating solar power generation system.

Figure 1 shows an overview of this power generation system.

The water supplied from the water supply pump 14 receives solar energy and evaporates in the condensing/heat collecting units 8, 9, and 10 of the evaporation section, and is separated into saturated steam and saturated liquid by the separator 15. The saturated liquid is circulated by the pump 16, and the saturated steam is passed through the light and heat collecting units 11, 1 in the superheating section.
At steps 2 and 13, it receives solar energy and becomes superheated steam, which is sent to the heat storage device 20. This steam is used as an energy source to rotate the turbine, while the remaining steam is sent to the heat storage tank 22 through the heat storage tank steam inflow valve 21.

In this plant, unlike a general turbine plant, the amount of solar radiation equivalent to the fuel for the boiler is a natural phenomenon and can only be secured during a limited period of time, so we took into consideration the amount for emergency use or preparation for startup the next morning. A certain amount is stored in this heat storage tank 22.
Therefore, even if there is no solar radiation, the heat storage tank 2
The heat dissipation operation for the capacity of 2 is the heat storage tank steam release valve 2.
It is possible via 3.

In such a solar thermal power generation plant, as shown in FIG. 2, the temperature of the steam flowing into the heat storage device 20 is controlled to be constant whenever the amount of solar radiation is more than a certain amount (for example, 2/4). Specifically, the outlet temperature of the superheater 13 is detected by the thermocouple 19 and the amount of spray flowing to the spray valve 17 is changed by the controller 18, or by reducing the steam flow rate when the amount of solar radiation decreases. Controlled to a constant value. However, when the amount of solar radiation decreases to 1/4 or less, the temperature cannot be kept constant even by spray or flow rate control, and the superheater outlet temperature fluctuates greatly. This means that it is out of the temperature control range due to static characteristics. The region indicated by hatching B in FIG. 2 is outside the steam conditions supplied to the turbine, and unless this is corrected in some way, moisture may enter the turbine and damage it. Conventionally, as a countermeasure against this problem, as shown in FIG. 1, the turbine inlet steam temperature is detected by a thermocouple 30, and the controller 31 opens and closes the temperature control valve 24 depending on the deviation from the set value, and corrects it with high-temperature steam supplied from the heat storage tank 22. Was.

In this way, the conventional method uses the steam stored in the heat storage tank 22 shown in Figure 1, so if the amount of solar radiation continues to decrease for a long time, the stored amount in the heat storage tank 22 is used up and an emergency occurs. This will impair the functionality of the
In the end, we had to give up on driving during low solar radiation.

In order to solve this problem, the present invention does not rely on heat dissipation operation from the heat storage tank 22 even in low solar radiation, and the superheater 13
It is possible to control the outlet temperature to a certain constant value.

In the present invention, when the amount of solar radiation decreases, a part of the light provided by the light collecting unit in the evaporating part is irradiated to the heat collecting unit in the superheating part to ensure the temperature of the steam supplied to the heat storage device 20.

FIG. 4 shows the light and heat condensing unit 8 shown in FIG.
Among the units 9, 10, 11, 12, and 13, the two units 10 and 11 sandwiching the separator 15 are embodied.
The heat collecting units 10B, 11B are reflected by the plane mirrors 3 provided at 0A, 11A and are opposed to each unit.
It is further converged by a curved mirror 4, and the energy is transmitted by a heat collecting tube 5 placed at the focal point. The plane mirror 3 is driven by a motor (not shown) to track the sun according to the position of the sun, which changes depending on the time and season.

In the present invention, when a certain amount or more of solar radiation can be secured, the light collecting unit 10 of the unit 10
The reflected light from a ₁ to a _o focused at A is directed to the curved mirror A ₁ of the opposing heat collection unit 10B, and the reflected light from b ₁ to b _o is controlled by the tracking device to the curved mirror B ₁ of 10B. ,
Similarly for unit 11, a ₁₁ to a _1o are A ₁₁ ,
b ₁₁ to b _1o controls to B ₁₁ . When _the interlock condition shown in _FIG .
A ₁₁ of B is irradiated, and b ₁ to b _o is irradiated to B ₁₁ . Another reflecting mirror (not shown) in the condensing unit 10A irradiates the evaporator with light.

As a result, even when the amount of solar radiation is low, the outlet temperature of the superheater 13 can be controlled, and steam at a certain constant temperature can be supplied to the heat storage device 20.

According to the present invention, even when the amount of solar radiation is low, it is possible to secure twice the amount of solar radiation than before, and it is possible to enter the temperature control range, solving the problems of the conventional method, and making continuous operation possible even when the amount of solar radiation is low.

[Brief explanation of the drawing]

Figure 1 shows an overview of the curved concentrator solar power generation system, and Figure 2 shows the amount of solar radiation from the rated value of 0.75KW/m ² to 1/
The behavior of each process variable when the number of steps is lowered by 4 is shown in FIG. 3, and the interlock to the solar tracking device is shown in FIG. 4, and a specific example of the present invention is shown in FIG. 10, 11...Heat collecting and concentrating unit, 10A, 1
1A... Light collecting unit, 10B, 11B... Heat collecting unit.

Claims (1)

[Claims] 1. A concentrating solar power generation system, which includes an evaporation part that evaporates water, a superheating part that superheats the steam evaporated in the evaporation part, and a first part that receives sunlight, reflects it, and irradiates it to the evaporation part. a group of reflective mirrors, a second group of reflective mirrors that receives sunlight, reflects it, and irradiates it to the overheating section; a reflector group drive source that adjusts the amount of light irradiated to the superheating section, and when the amount of solar radiation is below a predetermined value and the flow rate of steam output from the superheating section is above a predetermined value, the first reflector 1. A concentrating solar power generation temperature control system, characterized in that reflected light is supplied from a part of the group to the overheating section.