JP2016146737A - Cooling apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling apparatus of power conditioner capable of reducing thermal stress imposed on to a semiconductor element at a low cost.SOLUTION: The cooling apparatus detects inner temperature and outside temperature of a power conditioner. The cooling apparatus also detects the electric power generated by a solar power generator to thereby increase the cooling capacity by predicting temperature raise in the power conditioner before overheating. With this, a thermal stress imposed on to the semiconductor elements used in the power conditioner can be reduced.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a cooling device, and more particularly to a cooling device applicable to a power conditioner that is a power conversion device for photovoltaic power generation.

Conventionally, in this type of cooling device, a power conditioner device characterized in that outside air is taken in by a cooling fan to cool the power conditioner portion has been known. (For example, see Patent Document 1)
Hereinafter, the power conditioner apparatus will be described with reference to FIG.

  As shown in FIG. 5, a power conditioner device 101 (corresponding to a cooling device) that cools by taking in outside air has a power conditioner portion 103 and a cooling fan 104 disposed above the power conditioner portion 103 inside a housing 102. In addition, an intake port 105 is provided at the lower portion of the housing 102 and an exhaust port 106 is provided at the upper portion of the housing 102.

  When the cooling fan 104 is operated, cold outside air flows from an intake port 105 provided in the lower part of the casing 102 and cools through the power conditioner portion 103 which is a heating element. The air that has cooled and warmed the power conditioner 103 passes through the cooling fan, and is discharged to the outside of the housing 102 through an exhaust port 106 provided in the upper portion of the housing 102.

  However, by taking in outside air, dust and salt enter the inside and cause damage to the power conditioner device. Therefore, the internal air is cooled by the air conditioner without taking in outside air, and the power conditioner is turned off. There has also been known a power conditioner device which is characterized by cooling the inner portion.

  Hereinafter, the sealed power conditioner apparatus will be described with reference to FIG.

  As shown in FIG. 6, a power conditioner device 201 (corresponding to a cooling device) that cools without taking in outside air includes a power conditioner unit 203 inside a casing 202 and an air conditioner indoor unit above the power conditioner unit 203. 207 is disposed, and an air conditioner outdoor unit 208 is disposed outside the housing 202.

  The air conditioner indoor unit 207 is cooled and circulated in the room, and cooled through the power conditioner unit 203 that is a heating element. The amount of heat recovered by the air conditioner indoor unit 207 is released to the outside of the housing 202 by the air conditioner outdoor unit 208 provided outside the housing 202.

  However, since air conditioners consume a lot of power and are not economical, a power conditioner that uses an air heat exchanger, cools the internal air with low power consumption without taking in outside air, and cools the power conditioner section. A device has been proposed.

  Hereinafter, the power conditioner apparatus will be described with reference to FIG.

  As shown in FIG. 7, a sealed power conditioner device 301 (corresponding to a cooling device) that cools without taking in outside air is cooled inside the casing 302 and above the power conditioner portion 303 and the power conditioner portion 303. A fan 304 is disposed, an intake port 305 is disposed at the bottom of the wall surface of the housing 302, an exhaust port 306 is disposed at the top, and an air heat exchanger unit 309 is disposed outside. The air heat exchanger unit 309 is formed so that the outside air passage and the inside air passage are intersected with each other separated by a partition, and the outside air and the inside air are not mixed but exchange heat through the partition. is there.

When the cooling fan 304 is operated, air cooled by the heat exchange with the cold outside air in the air heat exchanger unit 309 flows from the air inlet 305 provided in the lower part of the wall surface of the housing 302, It cools through a certain inverter section 303. The air that has been warmed through the power conditioner unit 303 flows into the air heat exchanger unit 309 from an exhaust port 306 provided in the upper portion of the wall surface.
When an air heat exchanger is used, it is possible to prevent inflow of dust and salt into the interior, but 100% heat exchange is not possible, and the air cooled by the air heat exchanger has a higher temperature than the outside air. It is said that the cooling capacity will be lower than that using air conditioners.

Japanese Patent No. 4911531

  In such a cooling method for a power conditioner device, which is a conventional photovoltaic power conversion device, the temperature of the inside air is set to be equal to or lower than the temperature necessary for maintaining the functions of the components in the power conditioner device. Cooling. As the order in which the temperature inside the device rises, first, when the DC power generated by photovoltaic power generation is converted into AC power by the power conditioner unit, the temperature of the semiconductor element used in the power conditioner unit rises. . Next, the temperature of the entire power conditioner increases as the temperature of the semiconductor element increases. Furthermore, the temperature of the inside air rises as the temperature of the entire power conditioner increases. That's it.

  Therefore, a time difference occurs between the temperature rise of the semiconductor element and the temperature rise of the inside air. During cooling, operating the cooling fan after the temperature rises causes the inside air to drop in temperature, the temperature inside the air conditioner decreases as the temperature of the inside air decreases, and the temperature of the power conditioner decreases. . In this way, the temperature decreases in a chained manner.

  Therefore, a time difference occurs between the temperature drop of the inside air and the temperature drop of the semiconductor element. If the amount of power generation increases abruptly, there is a time difference in temperature rise and a time difference until the temperature falls, so the semiconductor elements used in the power conditioner section will not be able to cool in time, and the temperature will rise rapidly, There is a problem that stress is applied and the inverter is temporarily stopped or the cooling capacity is always operated at the maximum. In particular, when an air heat exchanger having a low cooling capacity is used, there is a problem that efficient cooling cannot be performed.

  The present invention solves the above-described conventional problems, and an object of the present invention is to provide a cooling device that efficiently cools, for example, a power conditioner device serving as a heating element.

  In order to achieve the above object, a cooling device that is a power conversion device for photovoltaic power generation according to the present invention detects an inside air temperature that is the temperature of the air inside the casing to be cooled provided with a heating element. Heat between the air inside the cooling target casing and the air outside the cooling target casing, and an outside air temperature detection unit that detects the outside air temperature that is the temperature of the air outside the cooling target casing. An air heat exchanger section that cools the air inside the casing to be cooled by exchanging, a generated power detection section that detects the amount of generated power input to the heating element, and the inside air temperature detection section A control unit that controls the cooling operation of the air heat exchanger unit based on the detected internal air temperature, the external air temperature detected by the external air temperature detection unit, and the amount of power detected by the generated power detection unit This is to achieve the intended purpose. .

  Since the cooling operation is performed before the temperature of the heating element rises by predicting the rise in the inside air temperature, it is economical and the temperature stress on the heating element can be reduced.

Schematic which shows the external appearance of the cooling device which concerns on Embodiment 1 of this invention. Functional block diagram showing a functional configuration of the cooling device according to the first embodiment of the present invention. Schematic which shows the external appearance of the cooling device which concerns on Embodiment 2 of this invention. The functional block diagram which shows the function structure of the cooling device which concerns on Embodiment 2 of this invention. Schematic of a conventional cooling device that cools by taking in outside air Schematic of a cooling device that cools with a conventional air conditioner Schematic of a cooling device that cools with a conventional air heat exchanger

  The cooling device according to the present invention includes an inside air temperature detection unit that detects an inside air temperature that is a temperature of air inside a cooling target housing having a heating element, and an outside air that is a temperature of air outside the cooling target housing. The air inside the cooling target casing is cooled by exchanging heat between the outside air temperature detection unit that detects the temperature and the air inside the cooling target casing and the air outside the cooling target casing. An air heat exchanger section, a generated power detection section for detecting the amount of generated power input to the heating element, an inside air temperature detected by the inside air temperature detection section, and an outside air temperature detected by the outside air temperature detection section And a control unit that controls the cooling operation of the air heat exchanger unit based on the amount of power detected by the generated power detection unit.

  With the above configuration, by detecting the generated power by the generated power detection unit, it is possible to predict an increase in the inside air temperature due to the temperature increase of the heating element that is correlated with the generated power, The sum of the inside air temperatures detected by the inside air temperature detection unit becomes the inside air arrival predicted temperature, and before the heating element rises in temperature from the outside air temperature detected by the outside air temperature detection unit and the inside air arrival prediction temperature, The control unit can perform a cooling operation suitable for achieving a target temperature at which the inside air is desired to be maintained, and has an effect of reducing the temperature stress applied to the heating element economically.

  Moreover, the solar power generation part which generate | occur | produces with sunlight is provided, and the said heat generating body is a power conditioner.

  With the above configuration, by detecting the generated power by the generated power detection unit, it is possible to predict the increase in the inside air temperature due to the temperature increase of the power conditioner that is correlated with the generated power, and the predicted increase in the inside air temperature And the inside air temperature detected by the inside air temperature detection unit become the inside air arrival predicted temperature, and the temperature of the power conditioner rises from the outside air temperature detected by the outside air temperature detection unit and the inside air arrival prediction temperature. In addition, the control unit can perform a cooling operation suitable for achieving a target temperature at which the inside air is desired to be maintained, and has an effect of reducing temperature stress applied to the power conditioner economically.

  Also, an inside air temperature detection unit that detects an inside air temperature that is the temperature of the air inside the cooling target housing having a heating element, and an outside air temperature that detects the outside air temperature that is the temperature of the air outside the cooling target housing An air heat exchanger unit that cools the air inside the casing to be cooled by exchanging heat between the air inside the casing to be cooled and the air outside the casing to be cooled. A solar radiation intensity detection unit that detects solar radiation intensity used for solar power generation, an internal air temperature detected by the internal air temperature detection unit, an external air temperature detected by the external air temperature detection unit, and the solar radiation intensity detection unit detected And a control unit that controls the cooling operation of the air heat exchanger unit based on the solar radiation intensity.

  With the above configuration, the solar radiation intensity detection unit is provided, and the generated power that is correlated with the solar radiation intensity is predicted by detecting the solar radiation intensity, and the inside air temperature due to the temperature rise of the heating element that is correlated with the generated power Increase of the inside air temperature and the sum of the inside air temperature detected by the inside air temperature detection unit becomes the inside air arrival prediction temperature, the outside air temperature detected by the outside air temperature detection unit, Before the temperature of the heating element rises from the predicted temperature of arrival of the inside air, the control unit can perform a cooling operation suitable for achieving a target temperature at which the inside air is desired to be maintained. It has the effect | action of reducing.

  Further, the solar power generation unit that generates power by sunlight, and a solar radiation intensity sensor that detects the solar radiation intensity irradiated to the solar power generation unit, the heating element is a power conditioner, the solar radiation intensity detection unit is The solar radiation intensity is detected based on the output signal from the solar radiation intensity sensor.

  With the above configuration, the solar radiation intensity detection unit is provided to detect the solar radiation intensity, thereby predicting the generated power correlated with the solar radiation intensity, and the inside air due to the temperature rise of the power conditioner correlated with the generated power. An increase in temperature can be predicted, and the total of the inside air temperature detected by the inside air temperature detection unit and the inside air temperature detection unit is the inside air arrival prediction temperature, and the outside air temperature detected by the outside air temperature detection unit, Before the temperature of the power conditioner rises from the predicted temperature of reaching the inside air, the control unit can perform a cooling operation suitable for achieving a target temperature at which the inside air is desired to be maintained. It has the effect of reducing thermal stress.

  In addition, the air heat exchanger section is an inside air intake fan that sucks air inside the cooling target casing into the air heat exchanger section at an upper portion of a casing contact surface that is a surface connected to the cooling target casing. And an internal air exhaust port for exhausting the internal air sucked into the air heat exchanger section into the inside of the casing to be cooled, and a surface not connected to the casing to be cooled. The outside air intake fan that sucks the outside air into the air heat exchanger part at the lower part of the non-casing contact surface, and the outside air sucked into the air heat exchanger part at the upper part of the non-housing contact surface It is good also as what was provided with the external air exhaust port exhausted to the said outside.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following embodiments are examples embodying the present invention, and do not limit the technical scope of the present invention. In addition, throughout the drawings, the same portions are denoted by the same reference numerals, and the second and subsequent descriptions are omitted. Further, in the drawings to be written, the description of the details of each part not directly related to the present invention is omitted.

(Embodiment 1)
As shown in FIG. 1, the cooling device 1 includes an inside air temperature detection unit 4, an outside air temperature detection unit 5, an air heat exchanger unit 6, a generated power detection unit 7, and a control unit 8.

  The inside air temperature detection unit 4 detects an inside air temperature that is the temperature of the air inside the power conditioner device 3 that is a casing to be cooled provided with the power conditioner unit 2 that is a heating element. The inside air temperature detection unit 4 is provided in the vicinity of the inside air intake fan 12 so that the temperature of the air inside the power conditioner device 3 can be detected.

  The outside air temperature detection unit 5 detects the outside air temperature that is outside the power conditioner device 3 and outside the cooling device 1. The outside air temperature detection unit 5 is provided in the vicinity of the outside air intake fan 10 and can detect the temperature of the outside air.

  The air heat exchanger section 6 cools the air inside the power conditioner device 3 by exchanging heat between the air inside the power conditioner device 3 and the air outside the power conditioner device 3. The air heat exchanger unit 6 is provided with an outside air intake fan 10, an outside air exhaust port 11, an inside air intake fan 12, an inside air exhaust port 13, and a heat exchange element.

  The outside air intake fan 10 sucks air outside the power conditioner device 3 and outside the cooling device 1 into the air heat exchanger section 6. The outside air intake fan 10 is provided at the lower part of the non-casing contact surface that is a side surface of the cooling device 1 and is not connected to the power conditioner device 3.

  The outside air exhaust port 11 is provided at an upper portion on the non-casing contact surface, and exhausts outside air sucked into the air heat exchanger section 6 by the outside air intake fan 10 to the outside.

  The inside air intake fan 12 sucks the air inside the power conditioner device 3 into the air heat exchanger unit 6. The inside air intake fan 12 is provided on the side surface of the cooling device 1 and on the upper portion of the housing contact surface that is a surface connected to the power conditioner device 3. In the present embodiment, the housing contact surface and the non-housing contact surface are provided on opposing surfaces of the cooling device forming the box.

  The inside air exhaust port 13 is provided at the lower part of the housing contact surface, and exhausts (circulates) the internal air sucked into the air heat exchanger section 6 by the inside air intake fan 12 again.

  The heat exchange element is housed inside the air heat exchanger section 6 and includes an internal air passage through which air inside the power conditioner device 3 passes and an outside air passage through which air outside the power conditioner device 3 passes. Are provided alternately and alternately. Heat can be exchanged between the air inside the power conditioner device 3 and the air outside the power conditioner device 3 by the arrangement of the air path.

  The generated power detection unit 7 is provided between the connection of the power conditioner unit 2 and the solar power generation unit 9, and is, for example, a clamp-type wattmeter, and the amount of generated power input from the power generation device to the power conditioner unit 2. Is detected. The generated power detection unit 7 is arranged on the wall surface of the power conditioner device 3 so as not to suppress the flow of wind at the inside air exhaust port 13 so as to be cooled by the circulating air from the inside air exhaust port 13.

  The control unit 8 cools the air heat exchanger unit 6 based on the inside air temperature detected by the inside air temperature detection unit 4, the outside air temperature detected by the outside air temperature detection unit 5, and the amount of power detected by the generated power detection unit 7. Control the behavior.

  Next, the relationship between the components of the cooling device 1 will be described with reference to FIG.

  As shown in FIG. 2, the control unit 8 is connected to the inside air temperature detection unit 4, the outside air temperature detection unit 5, and the inside air intake fan 12. The control unit 8 is constituted by, for example, a microcomputer. The control unit 8 acquires the inside air temperature from the inside air temperature detection unit 4 and the outside air temperature from the outside air temperature detection unit 5. Further, the control unit 8 adjusts the intake air amount of the inside air intake fan 12 and the outside air intake fan 10 based on, for example, the inside air temperature and the outside air temperature. Furthermore, the control unit 8 is connected to the generated power detection unit 7 and can acquire the generated power amount detected by the generated power detection unit 7. The control unit 8 determines the start of intake based on the increase / decrease of the generated power amount or adjusts the intake amount via each fan, which will be described in detail later.

  Moreover, the solar power generation part 9 is provided in the exterior of the power conditioner apparatus 3 as an example. The electric power generated by the solar power generation unit 9 is supplied to the power conditioner unit 2. At this time, the generated power is also transmitted to the generated power detection unit 7. The power conditioner unit 2 converts the generated DC power into AC power. The converted AC power is supplied to various loads via the output unit. In addition, household appliances etc. correspond to a load.

  Here, for example, if the conversion efficiency of the power conditioner unit 2 is 95%, 5% becomes a conversion loss and is released as heat.

  In other words, the amount of heat released due to conversion loss increases as the generated power increases. Therefore, by detecting the generated power supplied to the power conditioner unit 2 by the generated power detection unit 7, a rise value of the inside air temperature due to the temperature increase of the power conditioner unit 2 correlated with the generated power is predicted. be able to.

When the generated power is Pin, the conversion efficiency is η, and the increase value of the inside air temperature is Tu, the increase value Tu of the inside air temperature is
Tu = K × Pin × (1−η)
It can be expressed as.

  Here, K is a specific coefficient resulting from the heat capacity of the inside air of the power conditioner device 3. The power conditioner unit 2 is generally controlled so as to maximize the conversion efficiency, and the conversion efficiency η can be considered to be substantially constant. Therefore, the increase value Tu of the inside air temperature is substantially proportional to the generated power Pin.

  Specifically, the control unit 8 calculates an increase value of the inside air temperature based on the generated power detected by the generated power detection unit 7. For example, the increase value of the inside air temperature may be obtained from a data table obtained from the actual measurement data. Alternatively, the amount of heat generation may be calculated from the conversion efficiency, and the increase value of the inside air temperature may be obtained. The rise value of the inside air temperature is a temperature deviation that rises after a predetermined time with respect to the current inside air temperature. The sum of the rise value of the inside air temperature and the inside air temperature detected by the inside air temperature detecting unit 4 is the predicted arrival temperature of the inside air.

  The control unit 8 uses the outside air temperature detected by the outside air temperature detecting unit 5 and the calculated inside air arrival predicted temperature, and before the power conditioner unit 2 rises in temperature, a target temperature (for example, 60 ° C.) at which the inside air is desired to be kept. The outside air intake fan 10 and the inside air intake fan 12 suitable for the operation are operated. The cooling state of the power conditioner unit 2 is greatly influenced not only by the inside air temperature and the air volume of the inside air intake fan 12 but also by the inside air flow. Therefore, for example, the air volumes of the inside air intake fan 12 and the outside air intake fan 10 can be determined with settings stored in a data table created in advance based on the actually measured values. Thereby, the temperature stress concerning the semiconductor element used for the power conditioner part 2 economically, for example, IGBT element, can be reduced.

  The control unit 8 has predicted the reached temperature based on the generated power. Naturally, when the power generation amount detected by the generated power detection unit 7 increases / decreases, the inside air intake fan 12 and the outside air are proportionally proportional to this. A configuration in which the intake air volume with the intake fan 10 is increased or decreased may be employed. Also by such a procedure, the temperature stress can be reduced because the cooling can be performed before the temperature rises.

  In addition, the generated electric power supplied to the power conditioner part 2 was illustrated as a thing from solar power generation. However, the detection of the generated power by the generated power detection unit is effective as long as the amount of power generation is not limited to photovoltaic power generation.

  Moreover, although the power conditioner was illustrated as a heat generating body, if the calorific value changes according to the electric energy supplied, it will not limit to this.

(Embodiment 2)
The cooling device 1b shown in FIG. 3 replaces the generated power detection unit 7 in the first embodiment, and detects a solar radiation intensity detection unit 14 that detects outdoor solar radiation intensity, that is, the intensity of solar radiation used in the solar power generation unit 9. It has. Then, the control unit 8b cools the air heat exchanger unit 6 based on the inside air temperature detected by the inside air temperature detecting unit 4, the outside air temperature detected by the outside air temperature detecting unit 5, and the solar radiation intensity detected by the solar radiation intensity detecting unit 14. It differs from the first embodiment in that the operation is controlled.

  As shown in FIG. 4, a signal line from a solar radiation intensity sensor 15 that measures the intensity of solar radiation used by the solar power generator 9 for solar power generation is connected to the solar radiation intensity detector 14. The installation location of the solar radiation intensity detection unit 14 is the same as the installation location of the generated power detection unit 7 in the first embodiment.

  The solar radiation intensity sensor 15 is provided in the vicinity of the solar power generation unit 9, and for example, a thermoelectric or photoelectric sensor can be used.

  The solar radiation intensity detector 14 receives the signal from the solar radiation intensity sensor 15 and calculates the solar radiation intensity.

  In the solar power generation unit 9, the generated current (short-circuit current) changes in proportion to the solar radiation intensity, and the amount of generated power also changes accordingly. Therefore, the control unit 8b can predict the generated power from the value of the solar radiation intensity by using, for example, a data table obtained from actual measurement data. When the predicted power generation value is predicted (calculated), as shown in the first embodiment, it is possible to predict the increase value of the inside air temperature due to the temperature increase of the power conditioner unit 2 correlated with the generated power. .

  Even after predicting the increase value of the inside air temperature, it is possible to economically reduce the temperature stress by performing the same temperature control as in the first embodiment.

  Temperature rise is predicted from the amount of power generation and power consumption, and it can be cooled appropriately without delay, so it can be used in products that require cooling.

DESCRIPTION OF SYMBOLS 1,1b Cooling device 2 Power conditioner part 3 Power conditioner apparatus 4 Inside air temperature detection part 5 Outside air temperature detection part 6 Air heat exchanger part 7 Generated power detection part 8, 8b Control part 9 Solar power generation part 10 Outside air intake fan DESCRIPTION OF SYMBOLS 11 Outside air exhaust port 12 Inside air intake fan 13 Inside air exhaust port 14 Solar radiation intensity detection part 15 Solar radiation intensity sensor

Claims (5)

An inside air temperature detection unit that detects an inside air temperature that is the temperature of the air inside the casing to be cooled provided with a heating element;
An outside air temperature detector that detects the outside air temperature that is the temperature of the air outside the casing to be cooled;
An air heat exchanger section that cools the air inside the cooling target case by performing heat exchange between the air inside the cooling target case and the air outside the cooling target case;
A generated power detection unit for detecting the amount of generated power input to the heating element;
A control unit that controls the cooling operation of the air heat exchanger unit based on the inside air temperature detected by the inside air temperature detection unit, the outside air temperature detected by the outside air temperature detection unit, and the amount of power detected by the generated power detection unit. And a cooling device. It has a solar power generation unit that generates power using sunlight
The cooling device according to claim 1, wherein the heating element is a power conditioner. An inside air temperature detection unit that detects an inside air temperature that is the temperature of the air inside the casing to be cooled provided with a heating element;
An outside air temperature detector that detects the outside air temperature that is the temperature of the air outside the casing to be cooled;
An air heat exchanger section that cools the air inside the cooling target case by performing heat exchange between the air inside the cooling target case and the air outside the cooling target case;
A solar radiation intensity detector for detecting the solar radiation intensity used for solar power generation;
A control unit that controls the cooling operation of the air heat exchanger unit based on the inside air temperature detected by the inside air temperature detecting unit, the outside air temperature detected by the outside air temperature detecting unit, and the solar radiation intensity detected by the solar radiation intensity detecting unit. And a cooling device. A solar power generation unit that generates power by sunlight;
A solar radiation intensity sensor for detecting the solar radiation intensity irradiated to the solar power generation unit,
The heating element is a power conditioner;
The solar radiation intensity detector is
The cooling device according to claim 3, wherein the solar radiation intensity is detected based on an output signal from the solar radiation intensity sensor. The air heat exchanger section is
An inside air intake fan that sucks air inside the cooling target case into the air heat exchanger part at an upper part of a case contact surface that is a surface connected to the cooling target case;
An internal air exhaust port for exhausting the internal air sucked into the air heat exchanger section into the lower portion of the housing contact surface into the cooling target housing;
An outside air intake fan that sucks the external air into the air heat exchanger at the lower part of the non-casing contact surface that is a surface that is not connected to the cooling target housing;
The cooling device according to any one of claims 1 to 4, further comprising an outside air exhaust port that exhausts the outside air sucked into the air heat exchanger section to the outside at an upper portion of the non-casing contact surface.