JP6232252B2 - Solar heat utilization system - Google Patents

Description

  The present invention relates to a solar heat utilization system.

  Conventionally, a heat medium is supplied to a solar heat collector, the cold water in the heat storage tank is heated using the heat medium heated by receiving sunlight, and the hot water obtained by the heating is supplied to the home etc. A solar heat utilization system has been proposed (see Patent Documents 1 and 2).

  In such a solar heat utilization system, a heat medium is circulated by driving a pump. The pump starts operation when the temperature difference between the heat medium temperature in the solar heat collecting device and the heat storage temperature in the heat storage tank is equal to or higher than the first predetermined value, and is lower than the second predetermined value lower than the first predetermined value. Operation stops.

JP-A-63-213763 JP-A 63-207951

  In the solar heat utilization system, it is important to accurately measure the heat medium temperature from the solar heat collecting apparatus. However, in the conventional solar heat utilization system, the heat medium temperature of the solar heat collecting device during the pump stop tends to be detected differently depending on the mounting position of the temperature sensor. In particular, when a temperature sensor is installed in the return pipe for supplying the heat medium from the heat collector to the heat storage tank in the solar heat collector, the detected temperature of the heat medium tends to vary depending on the installation location. There is.

  Note that the heat medium temperature is not detected differently only when a temperature sensor is installed in the return pipe, but is detected differently due to various factors such as contamination of the heat collecting part of the solar heat collecting device. It is.

  When the temperature sensor is attached at a location where the temperature of the heat medium becomes low, the temperature difference is unlikely to be equal to or higher than the first predetermined value, and from the original temperature of the heat medium, the temperature difference is equal to or higher than the first predetermined value. In spite of this, the pump may not operate and the heat collection efficiency may be reduced.

  The above problem is not limited to the solar heat utilization system that supplies hot water stored in the heat storage tank to the home, etc., but also uses solar heat that uses the heat medium and heat stored in the heat storage tank for the operation of other equipment. This is a common problem in the system.

  The present invention has been made to solve such conventional problems, and an object thereof is to provide a solar heat utilization system capable of improving the heat collection efficiency.

  The solar heat utilization system of the present invention includes a heat collecting device that heats a heat medium by receiving sunlight, a heat storage tank that stores heat by introducing the heat medium heated by the heat collecting apparatus, and the heat storage tank. A pump that circulates the heat medium again to the heat storage tank through the heat collection device, a plurality of first temperature sensors that detect the temperature of the heat medium heated by the heat collection device, and a heat storage temperature in the heat storage tank The average value of the temperature difference between the second temperature sensor for detecting the temperature, the temperature of the heat medium detected by the plurality of first temperature sensors, and the heat storage temperature detected by the second temperature sensor is equal to or greater than a first predetermined value. Control means for operating the pump in the event that the value becomes equal to or less than a second predetermined value that is lower than the first predetermined value, and stopping the pump when the average value is lower than the first predetermined value. 1 or more to heat the heating medium by receiving sunlight A plurality of heat collector groups each constituted by a plurality of heat collectors, wherein the plurality of first temperature sensors are provided for two or more heat collector groups of the plurality of heat collector groups. The control means stops the pump for a predetermined time when the average value is not equal to or higher than the first predetermined value and a part of the differential temperature is equal to or higher than the first predetermined value while the pump is stopped. It is made to drive.

  According to the solar heat utilization system of the present invention, a part of the temperature difference between the temperature of the heat medium detected by the plurality of first temperature sensors and the heat storage temperature detected by the second temperature sensor is a first predetermined value. In such a case, the pump is operated for a predetermined time. For this reason, a heat medium will be stirred by the driving | operation of a pump. As a result, even if there is a difference in the temperature of the heat medium in the heat collector when the pump is stopped, the temperature of the heat medium in the heat collector is averaged by stirring, and the mounting position of the first temperature sensor has an effect. Thus, it is possible to reduce the frequency of occurrence of a situation where heat can be collected even though it can be collected. Therefore, it is possible to improve the heat collection efficiency.

  In the solar heat utilization system of the present invention, the control means detects the temperature of the heat medium detected by one of the plurality of first temperature sensors and the other first temperature sensors excluding the one. When the average value of the temperature of the heat medium that has been performed has a difference of a specified value or more, the one first temperature sensor or the heat collector group provided with the one first temperature sensor is in an abnormal state. It is preferable to judge.

  According to this solar heat utilization system, when the temperature of the heat medium detected by one first temperature sensor and the average value of the temperature of the heat medium detected by another first temperature sensor have a difference equal to or greater than a specified value The one temperature sensor or the heat collector group provided with the one first temperature sensor is determined to be in an abnormal state. Here, the case where there is a difference greater than a specified value with respect to the average value includes sensor failure, dirt on the panel surface of the heat collecting device, clogging of the flow path, and the like. Further, when the heat collector is of a vacuum tube type, the vacuum tube is broken. Therefore, when such a detection value is shown, it can be determined that the state is abnormal.

  In the above, the average value is not limited to the average value itself, but is a concept including a value obtained by further calculating the average value, that is, a value derived from the average value.

  According to the present invention, it is possible to provide a solar heat utilization system capable of improving the heat collection efficiency.

It is a schematic block diagram of the thermal storage system which concerns on embodiment of this invention. It is a block diagram which shows the detail of the solar thermal collector shown in FIG. It is a figure which shows the pump control by the control panel which concerns on this embodiment. It is a flowchart which shows the control method of the thermal storage system which concerns on this embodiment.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a heat storage system according to an embodiment of the present invention. As shown in FIG. 1, a heat storage system 1 according to the present embodiment performs heat storage using solar heat, and includes a solar heat collector (heat collector) 11, a heat storage tank 12, and a heat collection channel. 13 and a heat collecting pump (pump) 14.

  The solar heat collector 11 heats the heat medium by receiving sunlight, and is installed at a position that is easy to receive sunlight and has an inclination, for example, on a roof. As the heat medium, water, antifreeze, propylene glycol aqueous solution, or the like is used.

  The heat storage tank 12 introduces a heat medium heated by the solar heat collector 11 and stores heat. The heat storage tank 12 is a tank that stores a heat medium therein. Moreover, the heat storage tank 12 may store the heat of the introduced heat medium with a heat storage material. The heat storage tank 12 is connected to a heat utilization device (for example, an absorption chiller / heater) that operates using heat, and the heat stored in the heat accumulation tank 12 is used by the heat utilization device.

  In addition, when the heat storage tank 12 stores heat with a heat storage material, for example, magnesium hydroxide is used as the heat storage material, but is not limited thereto. Furthermore, when the heat medium is water and the heat storage tank 12 is a tank that stores water therein, the heat storage tank 12 may function as a so-called hot water storage tank, and hot water may be supplied to a home or the like. In addition, the heat storage tank 12 may be of a type including a heat exchanger.

  The heat collection channel 13 is a pipe that circulates the heat medium from the heat storage tank 12 to the heat storage tank 12 again through the solar heat collector 11. Among these, the flow path from the heat storage tank 12 to the solar heat collection apparatus 11 is referred to as a first heat collection flow path 13a, and the flow path from the solar heat collection apparatus 11 to the heat storage tank 12 is referred to as a second heat collection flow path 13b.

  The heat collection pump 14 is provided in the first heat collection flow path 13a of the heat collection flow path 13, and serves as a power source for circulating the heat medium from the heat storage tank 12 to the heat storage tank 12 again through the solar heat collecting apparatus 11. It is.

  Furthermore, in this embodiment, the heat storage system 1 includes a plurality of heat collector temperature sensors (a plurality of first temperature sensors) 15, a heat storage tank temperature sensor (second temperature sensor) 16, and a control panel (control means) 17. It has.

  The plurality of heat collector temperature sensors 15 detect the temperature of the heat medium heated by the solar heat collector 11 and transmit a signal corresponding to the heat medium temperature to the control panel 17. The heat storage tank temperature sensor 16 detects the temperature of the heat medium in the heat storage tank 12 (heat storage temperature of the heat storage tank 12), and transmits a signal corresponding to the heat medium temperature to the control panel 17.

  The control panel 17 includes a CPU (Central Processing Unit), and controls the entire heat storage system 1 by the CPU. In particular, in the present embodiment, the control panel 17 controls the heat collection pump 14 based on the temperature of the heat medium detected by the plurality of heat collector temperature sensors 15 and the heat storage temperature detected by the heat storage tank temperature sensor 16. .

  FIG. 2 is a configuration diagram showing details of the solar heat collecting apparatus 11 shown in FIG. 1. As shown in FIG. 2, the solar heat collector 11 is a so-called reverse return type heat collector, and includes a plurality (three) of heat collector groups 11 a to 11 c.

  The plurality of heat collector groups 11a to 11c introduce and heat the heat medium in parallel with each other, and a plurality (five) of the heat collectors 11a1 to 11 heat the heat medium by receiving sunlight. 11a5, 11b1 to 11b5, 11c1 to 11c5 are respectively configured.

  If it demonstrates in detail, in addition to the heat collector group 11a-11c, the solar-heat collector 11 will be provided with the outgoing piping 11d, the branch outgoing piping 11e1-11e3, the return piping 11f, and the return branching piping 11g1-11g3. .

  The forward piping 11d introduces the heat medium from the heat storage tank 12. The branch outgoing pipes 11e1 to 11e3 are pipes that are connected at one end to the outgoing pipe 11d and liquid-feed the heat medium from the outgoing pipe 11d to the respective heat collector groups 11a to 11c.

  Specifically, the first branch outgoing pipe 11e1 has one end connected to the outgoing pipe 11d and the other end connected to the first heat collector group 11a. The second branch forward pipe 11e2 has one end connected to the forward pipe 11d, the other end connected to the second heat collector group 11b, and is connected in parallel to the first branch forward pipe 11e1. The third branch forward pipe 11e3 has one end connected to the forward pipe 11d, the other end connected to the third heat collector group 11c, and is connected in parallel to the first and second branch forward pipes 11e1 and 11e2. .

  Furthermore, one end of the first branch outgoing pipe 11e1 is connected to the front side (that is, the side closer to the heat collecting pump 14 and the heat storage tank 12) of the outgoing pipe 11d than the other branch outgoing pipes 11e2 and 11e3. . One end of the third branch forward pipe 11e3 is connected to the end of the forward pipe 11d, and one end of the second branch forward pipe 11e2 is an intermediate point in the forward pipe 11d (that is, the first branch forward pipe 11e1 and the forward pipe). Between the connection point of the pipe 11d and the connection point of the third branch forward pipe 11e3 and the forward pipe 11d).

  In addition, since the first heat collector group 11a includes a plurality (five) of heat collectors 11a1 to 11a5, the first branch outgoing pipe 11e1 has a heat medium in parallel with each of the heat collectors 11a1 to 11a5. The other end is branched into a plurality (5) so as to be supplied. Since the second and third heat collector groups 11b and 11c also include a plurality (five) of heat collectors 11b1 to 11b5 and 11c1 to 11c5, respectively, the second and third branch outgoing pipes 11e2 and 11e3 are provided. The other end side is branched into a plurality (five) so that the heat medium is supplied in parallel to each of the heat collectors 11b1 to 11b5, 11c1 to 11c5.

  The return pipe 11f discharges the heated heat medium to the heat storage tank 12 side. The branch return pipes 11g1 to 11g3 are pipes whose other ends are connected to the return pipe 11f, and for sending the heat medium from each of the heat collector groups 11a to 11c to the return pipe 11f.

  Specifically, the first branch return pipe 11g1 has one end connected to the first heat collector group 11a and the other end connected to the return pipe 11f. The second branch return pipe 11g2 has one end connected to the second heat collector group 11b, the other end connected to the return pipe 11f, and connected in parallel to the first branch return pipe 11g1. The third branch return pipe 11g3 has one end connected to the third heat collector group 11c, the other end connected to the return pipe 11f, and connected in parallel to the first and second branch return pipes 11g1 and 11g2. Yes.

  Furthermore, the other end of the first branch return pipe 11g1 is connected to the end of the return pipe 11f. The other end of the third branch return pipe 11g3 is connected to the near side (that is, the side closer to the heat storage tank 12) than the other branch return pipes 11g1 and 11g2. The other end of the second branch return pipe 11g2 is an intermediate point in the return pipe 11f (that is, a connection point between the first branch return pipe 11g1 and the return pipe 11f, and a connection point between the third branch return pipe 11g3 and the return pipe 11f). Between).

  In addition, since the first heat collector group 11a includes a plurality (five) of heat collectors 11a1 to 11a5, the first branch return pipe 11g1 receives a heat medium from each of the heat collectors 11a1 to 11a5 in parallel. One end is branched into a plurality (five) so as to be accepted. Since the second and third heat collector groups 11b and 11c also include a plurality (five) of heat collectors 11b1 to 11b5 and 11c1 to 11c5, respectively, the second and third branch return pipes 11g2 and 11g3 are provided. Are branched into a plurality (five) on one end side so as to receive the heat medium in parallel from the respective heat collectors 11b1 to 11b5, 11c1 to 11c5.

  Since it is such a structure, the some heat collector groups 11a-11c will mutually introduce a heating medium in parallel, and will heat it.

  Note that the configuration of the solar heat collector 11 is not limited to that shown in FIG. 2, and may be connected to a pipe so as to be, for example, a direct return system or may be configured by a vacuum tube type heat collector. In particular, when the solar heat collecting apparatus 11 is of a vacuum tube type, it is needless to say that the plurality of heat collectors 11a1 to 11a5, 11b1 to 11b5, 11c1 to 11c5 are constituted by vacuum tube type heat collecting tubes.

  Furthermore, although the several heat collector group 11a-11c is equipped with multiple heat collectors 11a1-11a5, 11b1-11b5, 11c1-11c5, respectively, the structure provided not only in this but only one may be sufficient. .

  In the solar heat collecting apparatus 11 as described above, the heat medium temperature tends to be detected differently depending on the mounting position of the heat collecting temperature sensor 15. Furthermore, when only a part of the surface of the heat collector is dirty, the solar heat collector 11 has a heat medium temperature at the plurality of heat collector groups 11a to 11c regardless of the attachment position of the heat collection temperature sensor 15. May cause a difference.

  Therefore, in the present embodiment, the plurality of heat collector temperature sensors 15 are provided for each of the heat collector groups 11a to 11c as shown in FIG. Specifically, the first heat collector temperature sensor 15a is provided on the outlet side of the first return branch pipe 11g1 provided for the first heat collector group 11a, and the second heat collector temperature sensor 15b is the second heat collector temperature sensor 15b. A third heat collecting device temperature sensor 15c is provided on the outlet side of the second return branch pipe 11g2 provided for the heat collector group 11b, and a third return branch pipe provided for the third heat collector group 11c. 11g3 outlet side.

  The plurality of heat collector temperature sensors 15 are not limited to one for each heat collector group 11a to 11c, and two for each heat collector group 11a to 11c. Alternatively, the number of sensors attached to each of the heat collector groups 11a to 11c may be different.

  Further, in the example shown in FIG. 2, the plurality of heat collector temperature sensors 15 are provided for all the heat collector groups 11 a to 11 c, but not limited thereto, two or more heat collector groups ( For example, what is necessary is just to be provided in the 1st and 2nd heat collector group 11a, 11b).

  In addition, the plurality of heat collector temperature sensors 15 are preferably provided at the same position in each of the heat collector groups 11a to 11c. That is, in the example shown in FIG. 2, the plurality of heat collector temperature sensors 15 are provided on the outlet side of the return branch pipes 11g1 to 11g3, respectively, and are provided at the same position. This is because the heat collecting pump 14 can be operated more accurately in the processing described later by providing the same position in this way.

  FIG. 3 is a diagram illustrating pump control by the control panel 17 according to the present embodiment. First, it is assumed that the heat collection pump 14 is stopped. In this state, the control panel 17 calculates the temperature difference between the temperature of the heat medium detected by the plurality of heat collector temperature sensors 15 and the temperature of the heat medium (heat storage temperature) detected by the heat storage layer temperature sensor 16. calculate. Next, the control panel 17 calculates the average value of the differential temperatures.

  When it is determined that the average value is equal to or higher than T1 ° C. (first predetermined value), the control panel 17 heat collecting pump 14 is operated. Further, when it is determined that the differential temperature is equal to or lower than T2 ° C. (second predetermined value) lower than T1 ° C. during the operation of the heat collection pump 14, the control panel 17 stops the heat collection pump 14.

  The above is the basic operation of pump control by the control panel 17. Further, in the present embodiment, the control panel 17 executes the following control.

  FIG. 4 is a flowchart showing a control method of the heat storage system 1 according to the present embodiment. In addition, the process shown in FIG. 4 is repeatedly performed until the heat storage system 1 stops.

  First, it is assumed that the heat collection pump 14 is stopped. In this state, as shown in FIG. 4, the control panel 17 calculates an average value of the differential temperatures and determines whether the average value is equal to or higher than T1 ° C. (S1). When it is determined that the average value is equal to or higher than T1 ° C. (S1: YES), the control panel 17 starts the operation of the heat collecting pump 14 (S2).

  Next, the control panel 17 refers to the detected temperature of each of the plurality of heat collecting device temperature sensors 15, and removes the temperature of the heat medium detected by one of the plurality of first temperature sensors 15 and the other one. It is determined whether the average value of the temperature of the heat medium detected by the first temperature sensor 15 has a difference equal to or greater than a specified value (S3). More specifically, the control panel 17 determines whether the difference between the temperature detected by the first heat collector temperature sensor 15a and the temperature detected by the second and third heat collector temperature sensors 15b, 15c is greater than a specified value. Next, it is determined whether the difference between the detected temperature of the second heat collector temperature sensor 15b and the detected temperature of the first and third heat collector temperature sensors 15a and 15c has a difference equal to or greater than a specified value. Next, it is determined whether or not the difference between the temperature detected by the third heat collector temperature sensor 15c and the temperature detected by the first and second heat collector temperature sensors 15a and 15b is greater than a specified value. When it is determined that there is no heat collector temperature sensor 15 having a difference equal to or greater than the specified value (S3: NO), the process proceeds to step S5.

  On the other hand, if it is determined that there is a heat collector temperature sensor 15 having a difference equal to or greater than a specified value (S3: YES), the control panel 17 determines whether the heat collector temperature sensor 15 having a difference equal to or greater than a specified value or the sensor 15 is present. It judges that it is in an abnormal state about the provided heat collector groups 11a to 11c, and outputs a display and sound to that effect (S4). Examples of the abnormality include failure of the heat collector temperature sensor 15 having a difference of a specified value or more, contamination on the surface of the heat collector of the solar heat collector 11, clogging of the flow path, and the like. Moreover, when the heat collectors 11a1 to 11a5, 11b1 to 11b5, and 11c1 to 11c5 are vacuum tube type heat collectors, the vacuum tube is broken. After output, the process proceeds to step S5.

  In step S5, the control panel 17 calculates an average value of the differential temperatures and determines whether the average value is T2 ° C. or less (S5). When it is determined that the average value is T2 ° C. or less (S5: YES), the control panel 17 stops the operation of the heat collecting pump 14 (S6). Then, the processing shown in FIG. 4 proceeds to step S1. On the other hand, when it is determined that the average value is not equal to or lower than T2 ° C. (S5: NO), the process proceeds to step S2.

  When it is determined that the average value is not equal to or higher than T1 ° C. (S1: NO), the control panel 17 detects each temperature of the heat medium detected by the plurality of heat collector temperature sensors 15 and the heat storage tank temperature sensor 16. It is determined whether a part of the temperature difference from the temperature of the heat medium that has been performed is equal to or higher than T1 ° C. (S7).

  When it is determined that all of them are not T1 ° C. or higher (S7: NO), the process proceeds to step S1. On the other hand, when it is determined that a part of the temperature is T1 ° C. or higher (S7: YES), the control panel 17 starts the operation of the heat collecting pump 14 (S8). As a result, the heat medium is agitated, and even if there is a difference in the heat medium temperature in the solar heat collector 11 when the pump is stopped, the heat medium temperature in the solar heat collector 11 is averaged by the agitation. The situation where the operation of the heat collecting pump 14 in step S2 is not performed due to the mounting position of the heat collecting device temperature sensor 15 is prevented.

  Next, the control panel 17 determines whether t minutes have elapsed from the start of operation (S9). If it is determined that t minutes have not elapsed (S9: NO), the process proceeds to step S8. On the other hand, when it is determined that t minutes have elapsed (S9: YES), the control panel 17 determines that the stirring of the heat medium has been completed and stops the operation of the heat collecting pump 14 (S6). Then, the processing shown in FIG. 4 proceeds to step S1.

  Thus, according to the heat storage system 1 according to the present embodiment, the temperature difference between each temperature of the heat medium detected by the plurality of heat collector temperature sensors 15 and the heat storage temperature detected by the heat storage tank temperature sensor 16. Among these, when a part becomes T1 degreeC or more, the heat collection pump 14 is operated for t minutes. For this reason, the heat medium is agitated by the operation of the heat collecting pump 14. As a result, even if there is a difference in the heat medium temperature in the solar heat collector 11 when the heat collection pump 14 is stopped, the heat medium temperature in the solar heat collector 11 is averaged by stirring, and the heat collector temperature in the solar heat collector 11 is averaged. The frequency of occurrence of a situation in which heat is not collected even though the heat can be collected due to the mounting position of the heat device temperature sensor 15 can be suppressed. Therefore, it is possible to improve the heat collection efficiency.

  Further, when the temperature of the heat medium detected by one heat collector temperature sensor 15 and the average value of the temperature of the heat medium detected by another heat collector temperature sensor 15 have a difference equal to or more than a specified value, It is determined that one heat collector temperature sensor 15 or the heat collector groups 11a to 11c provided with the heat collector temperature sensor 15 is in an abnormal state. Here, the case where there is a difference greater than a specified value with respect to the average value includes sensor failure, contamination on the surface of the heat collector of the solar heat collector 11, clogging of the flow path, and the like. Moreover, when the heat collectors 11a1 to 11a5, 11b1 to 11b5, and 11c1 to 11c5 are vacuum tube type heat collectors, the vacuum tube is broken. Therefore, when such a detection value is shown, it can be determined that the state is abnormal.

  As described above, the present invention has been described based on the embodiment, but the present invention is not limited to the above embodiment, and may be modified without departing from the gist of the present invention.

1 ... Solar heat utilization system 11 ... Solar heat collector (heat collector)
11a to 11c: Multiple heat collector groups 11a1 to 11a5, 11b1 to 11b5, 11c1 to 11c5 ... Tank 13 ... Heat collection channel 14 ... Heat collection pump (pump)
15 ... A plurality of heat collecting device temperature sensors (a plurality of first temperature sensors)
16 ... thermal storage tank temperature sensor (second temperature sensor)
17 ... Control panel (control means)

Claims (2)

A heat collector that heats the heat medium by receiving sunlight; and
A heat storage tank for storing heat by introducing a heat medium heated by the heat collecting device; and
A pump for circulating a heat medium from the heat storage tank to the heat storage tank again through the heat collecting device;
A plurality of first temperature sensors for detecting the temperature of the heat medium heated by the heat collector;
A second temperature sensor for detecting a heat storage temperature in the heat storage tank;
The pump is operated when the average value of the temperature difference between each temperature of the heat medium detected by the plurality of first temperature sensors and the heat storage temperature detected by the second temperature sensor is equal to or greater than a first predetermined value. Control means for stopping the pump when the average value is equal to or lower than a second predetermined value lower than the first predetermined value,
The heat collector has a plurality of heat collector groups each constituted by one or a plurality of heat collectors that heat the heat medium by receiving sunlight.
The plurality of first temperature sensors are provided for two or more heat collector groups of the plurality of heat collector groups,
The control means operates the pump for a predetermined time when the average value is not equal to or higher than the first predetermined value and a part of the differential temperature is equal to or higher than the first predetermined value while the pump is stopped. A heat storage system characterized by The control means includes a temperature of the heat medium detected by one of the plurality of first temperature sensors, and an average value of the temperature of the heat medium detected by other first temperature sensors excluding the one. 2 is determined to be in an abnormal state with respect to the one first temperature sensor or the heat collector group provided with the one first temperature sensor. The heat storage system described in 1.

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