JP2003021447A - Water cooled type electric apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water cooled type electric apparatus wherein cooling water can cool the apparatus without being frozen, even when the water temperature of a brine becomes 0 deg.C or below. SOLUTION: Heat is stored beforehand in the cooling water by raising the water temperature of the cooling water. Cooling of this apparatus is started when the cooling water and the brine are judged to be in a state of not being frozen even when heat exchange is conducted between them.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to cooling for releasing heat generated when a water-cooled electric device is operated to the outside.

[0002]

2. Description of the Related Art FIG. 3 is an electrical diagram referring to a conventional water-cooled cooling system shown in, for example, "Cooling Technology for Electronic Equipment" (published on December 20, 1987) edited by Gihodo Publishing and the Japan Society of Mechanical Engineers. It is a block diagram of a device. In the figure, 1 is a water-cooled electric device, 2 is a water-cooling pump for circulating cooling water in the water-cooled electric device 1, 3 is a heat exchanger, and 5 is for keeping the water pressure of the cooling water above atmospheric pressure. A serge tank, 6 is a water-cooled electric device 1, a water-cooling pump 2, a heat exchanger 3, a serge.
It is a pipe for connecting the ditank 5 and supplying cooling water. Further, 7 is an antifreeze liquid pump for circulating the antifreeze liquid, 8 is a cooler for radiating heat generated by a water-cooled electric device to the outside air, 9 is a surge tank for keeping the water pressure of the antifreeze liquid above atmospheric pressure, Reference numeral 10 is a pipe for connecting these to circulate the antifreeze liquid. In such a water-cooled electric device, the water-cooled electric device 1, the pipe 6 and the like may be provided indoors, and the cooler 8, the pipe 10 and the like may be provided outdoors.

The water-cooled electric equipment constructed in this way is
At the start of operation when the temperature is low such as in winter, the water temperature of the antifreeze liquid (secondary cooling water) circulating in the pipe 10 provided on the outdoor side may be 0 ° C. or lower. Alternatively, the water temperature of the antifreeze liquid may be 0 ° C. or lower when the cooling device of the water-cooled electric device is stopped and then the cooling device is operated again. When the water temperature of the antifreeze liquid (secondary cooling water) is 0 ° C. or lower as described above, the water temperature of the primary cooling water after the operation of the pump is 0 as shown in FIG. It will be below ℃.
As a result, the primary cooling water may freeze, causing a problem such as damage to the heat exchanger.

[0004]

In the conventional water-cooled electric equipment as described above, the water temperature of the cooling water for cooling the water-cooled electric equipment is 0 ° C. in the operating start when the temperature is low such as in winter. There was a problem that the heat exchanger and the like were destroyed in the following cases. The present invention has been made to solve the above problems, and an object of the present invention is to obtain a water-cooled electric device that performs cooling without cooling water at 0 ° C or lower.

[0005]

A water-cooled electric device according to a first aspect of the present invention circulates the cooling water for cooling the electric device and the cooling water in a primary cooling system passing through the electric device. First pipe, a water cooling pump for circulating cooling water in the first pipe, and a heat exchanger connected to the first pipe for exchanging heat radiated by an electric device. And an antifreeze liquid which is a secondary cooling water for exchanging heat with the heat radiated by this heat exchanger, and a heat exchanger and a cooler for releasing the heat absorbed by the antifreeze liquid to the outside air. A second pipe for circulating the antifreeze in the secondary cooling system, an antifreeze pump for circulating the antifreeze in the second pipe, and a first temperature detecting means for measuring the temperature of cooling water, A second temperature detecting means for measuring the temperature of the antifreeze liquid, and heat for cooling water. From the heat source that gives the amount and the heat amount to the cooling water by the heat source, the heat amount is calculated from the detection result of the cooling water temperature by the first temperature detecting means and the detection result of the antifreeze liquid temperature by the second temperature detecting means. It is determined whether the temperature of the cooling water increased by being given a temperature that does not freeze even if heat exchange is performed with the antifreeze liquid,
When the temperature of the cooling water is such that it does not freeze, the control is performed so as to start cooling the electric device.

In the water-cooled electric device according to the second aspect of the invention, the heat source is heat generated by the water-cooling pump during operation,
The control means first starts the water cooling pump to give a quantity of heat to the cooling water, and the detection result of the cooling water temperature by the first temperature detecting means and the antifreezing liquid by the second temperature detecting means are obtained.
Based on the temperature detection result, it is determined whether the temperature of the cooling water increased by the amount of heat given by the water cooling pump does not freeze even if it exchanges heat with the antifreeze liquid. When there is no temperature, control is performed so as to start the antifreeze pump.

In the water-cooled electric device according to the third aspect of the present invention, the control means is: T _n : temperature at which cooling water freezes T _F : temperature of antifreezing liquid when starting cooling of the electric device T _h : after being heated temperature _{T C} of the cooling water: the temperature of the after heated cooling water and antifreeze has heat exchange _{V 1:} volume of the cooling water _{V 2:} when the volume of _{antifreeze, T h ≧ T C + V} 2 / V 1 and controls so as to satisfy the _(T n _-T F).

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a water-cooled electric device according to an embodiment of the present invention.
In the figure, 1 is a water-cooled electric device, 2 is a water-cooling pump for circulating cooling water in the water-cooled electric device 1, 3 is a heat exchanger, and 5 is for maintaining the water pressure of the cooling water at atmospheric pressure or higher. Is a surge tank, and 6 is a pipe. A water cooling type electric device 1, a water cooling pump 2, a heat exchanger 3 and a surge tank 5 are connected by a pipe 6 to supply cooling water. The system connected by the pipe 6 is referred to as a primary cooling system 20. As an electric device of the water-cooled electric device 1, for example, there is a power converter using a thyristor or the like. For example, the water-cooled electric device 1 and the pipe 6 are provided indoors.

Reference numeral 7 is an antifreeze pump for circulating the antifreeze liquid, 8 is a cooler for radiating the heat generated by water-cooled electric equipment to the outside air, and 9 is a surge tank for keeping the water pressure of the antifreeze liquid above atmospheric pressure. Reference numeral 10 is a pipe. The pipe 10 is again connected to the cooler 8 via the cooler 8, the heat exchanger 3, the antifreeze pump 7, and the surge tank 9, and the pipe 10 circulates the antifreeze liquid. The system connected by the pipe 10 is referred to as a secondary cooling system 30. For example, the cooler 8 and the pipe 10 are provided outdoors. Further, 40 is a controller, 41 is a thermometer, and 42 is an instrumentation cable for outputting the output signal of the thermometer 41 to the controller 40. Reference numerals 43 and 44 are control cables for outputting an operation or stop command to the water cooling pump 2 and the antifreeze pump 7, respectively. Reference numeral 51 is a thermometer for measuring the temperature of the antifreezing liquid which is the secondary cooling water. Reference numeral 52 is an instrumentation cable for outputting the output signal of the thermometer 51 to the controller 40.
The controller 40 outputs an operation / stop command to the antifreezing liquid pump 7 and the water cooling pump 2 and controls the antifreezing liquid pump 7 and the water cooling pump 2 based on the temperatures of the antifreezing liquid and the cooling water. Reference numeral 60 is a heat source for giving an amount of heat to the cooling water. An example of the control means is the controller 40. Further, as the first and second temperature detecting means, for example, there are a thermometer 41 and a thermometer 51.

The operation will be described below. In the water-cooled electric device configured as described above, when the device is operated in the winter season or when the cooling of the water-cooled electric device that has been operating is stopped and the operation is restarted, as shown in FIG. Sometimes the water temperature is below 0 ° C. When the water temperature of the antifreeze liquid is 0 ° C. or lower, the water-cooled electric device is first cooled by operating the water-cooling pump 2 and the cooling water is heated to 30 ° C. by the heat of the water-cooling pump 2. Up to. When the water cooling pump 2 is operated, heat is generated from the pump motor, and the heat raises the temperature of the cooling water. Here, the exhaust heat of the motor of the water cooling pump 2 is used, but in addition, heat may be applied to the cooling water by an external heat source to raise the water temperature. When applying heat from the outside, the heat source 60 may be used.
The heat source 60 is, for example, a heater provided in a pipe, and the temperature of the cooling water may be first raised by this heater.
At this time, after the temperature of the cooling water rises, the water cooling pump 2 and the antifreezing liquid pump 7 may be started to perform cooling. When the water cooling pump 2 is operated to raise the temperature of the cooling water, the heat generated by the motor of the water cooling pump 2 substitutes for the heat source 60.

First, when cooling the water-cooled electric equipment, the water-cooling pump 2 is started to bring the temperature of the cooling water to 30 degrees.
After raising the temperature to ℃, from the controller 40 to the antifreeze pump 7
Create a sequence to output the operation command to. After the water cooling pump 7 is started and the water temperature of the cooling water rises to a predetermined temperature, the operation of the antifreeze pump 7 is started at the timing shown in FIG. In this way, the heat exchanger 3 exchanges heat between the cooling water of 30 ° C. and the antifreeze liquid of 0 ° C. or less, which has accumulated heat due to the heat generation of the water cooling pump 2. In the case of FIG. 2, the antifreeze liquid has reached −3 ° C. when cooling is started. The amount of heat stored in the cooling water (water temperature 1 in Fig. 2
(Amount of heat stored by increasing the temperature from 5 ℃ to 30 ℃)
As a result, even if the heat amounts of the cooling water of 30 ° C. and the antifreeze liquid of 0 ° C. or less are exchanged with each other, the water temperature of the antifreeze liquid can be maintained at 0 ° C. or more as shown in FIG. In this case, the water temperature of the antifreeze is 5
It will be around ℃.

In the water-cooled electric equipment constructed as described above,
When the antifreezing liquid, which is the cooling water for the secondary cooling system, is 0 ° C. or less, such as during winter, when cooling is performed, the water cooling pump 2 for the primary cooling system is first operated. The cooling water in the pipe 6 is circulated by the water cooling pump 2, and the temperature of the cooling water is raised by the heat generated by the water cooling pump 2. At this time, even if heat is exchanged with the antifreeze liquid that is 0 ° C or less,
After the heat exchange, the water temperature of the cooling water is raised to a temperature at which the water temperature of the antifreeze liquid and the cooling water does not fall below 0 ° C. After raising the temperature of the cooling water to a predetermined temperature, the antifreeze pump 7 is started to perform heat exchange between the cooling water and the antifreeze liquid. By cooling in this way, even if the operation of water-cooled electrical equipment is started in winter, the cooling water will be 0 ° C.
Since it does not occur below, there is an effect that the water-cooled electric device can be normally cooled without breaking the heat exchanger due to freezing.

The temperature of the cooling water of the primary cooling system is raised to 30 ° C. because the cooling device for such a water-cooled electric device is operated in the secondary cooling system before the operation is started in winter. The water temperature of the antifreeze is often around -5 ° C. In addition, the cooling water volume V ₁ of the primary cooling system and the antifreeze water volume V _{2 of the} secondary cooling system
Often has a relationship of V ₁ / V ₂ = 1/3. Therefore, when heat is exchanged between the antifreeze liquid and the cooling water, the temperature of the cooling water is raised by the heat generated by the water cooling pump 2 because the temperature of the antifreeze liquid and the cooling water does not fall below 0 ° C. after the heat exchange. Ask if it needs to be warmed. Here, it is assumed that the water temperature of the antifreeze liquid is −3 ° C.

Δθ ₂ (K) = Δθ ₁ (K) × (V ₁ / V ₂ ) Equation (1) = 25 × 1 / 3≈8 (K) Δθ ₂ (K): Antifreeze at 0 ° C. Temperature rise value Δθ ₁ (K) of antifreeze required to raise the temperature above: Water temperature difference when cooling water temperature of 30 ° C. is lowered to 5 ° C. = 25 (K) where K is temperature The difference is shown and the unit is ° C. V ₁ : Water volume of cooling water = 1 V ₂ : Water volume of antifreeze = 3

As described above, according to the formula (1), the result of heating the cooling water at 15 ° C. to 30 ° C., then starting the antifreezing liquid pump and exchanging heat with the antifreezing liquid at 0 ° C. or lower is 0. It can be seen that the water temperature of the antifreeze below ℃ can be raised by 8 ℃. Here, since the water temperature of the antifreeze is −3 ° C., if the temperature of 8 ° C. can be raised, the water temperature of the antifreeze will be 5 ° C.
As can be seen from FIG. 2, the temperatures of the primary cooling water (cooling water) and the secondary cooling water (antifreeze liquid) are approximately equal to each other near 5 ° C.
Note that V ₁ / V ₂ does not necessarily have to have a relationship of 1/3, and V ₁ / V ₂ has only to satisfy a relationship of 1/3 or more. Even if V ₁ / V ₂ is 1/3 or less, the water temperature of the cooling water may be raised to 30 ° C. or more. Even when the water temperature of the antifreeze liquid is −5 ° C. or lower, the appropriate temperature rise value may be determined using the relationship of the equation (1). Then, an appropriate Δθ ₂ (K) can be obtained. This Δ
θ ₂ (K) is a temperature value capable of increasing the temperature of the antifreeze liquid when heat is exchanged between the primary cooling water (cooling water) and the secondary cooling water (antifreeze liquid).

In the above, the temperature value Δθ ₂ which can raise the temperature of the antifreeze liquid was obtained by exchanging heat between the antifreeze liquid and the cooling water in a specific case. T _n : temperature at which cooling water freezes (0 ° C .: when cooling water is water) T _F : temperature of antifreeze liquid when starting cooling of water-cooled electric equipment _TC : heated cooling water antifreeze temperature T after it has exchanged heat _h: elevated temperature V ₁ of the cooling water _after: quantity of cooling water (primary cooling water) V _2: freezing the water of the antifreeze (secondary coolant) cooling water Without trying to find the conditions for increasing the temperature of the antifreeze. Δθ ₂ (K) = Δθ ₁ (K) × (V ₁ / V ₂ ) ... (1) = (T _h −T _C ) × (V ₁ / V ₂ ) _TF + Δθ ₂ (K) ≧ T _n · · · (2) formula (2) is an expression (1), when obtaining the _{T h, T h ≧ T C} + V 2 / V 1 (T n -T F) ··· (3) The value of each parameter may be set so as to satisfy the relationship of Expression (3). Here, when water is used in the primary cooling water, so the _{T n ≧ 0 ℃, T h} ≧ T C - can be expressed as _{(V 2 / V 1) ×} T F ··· (4) .

From the above, when the water temperature of the antifreeze liquid is 0 ° C. or less in winter, even if the water-cooled electric equipment is cooled, the value of each parameter is satisfied so as to satisfy the relationship of the expression (3). If the water cooling pump is set to start first, even if heat is exchanged between the cooling water and the antifreeze liquid at 0 ° C. or less, the temperature of the cooling water and the antifreeze liquid after the heat exchange will be zero. It can be above ℃. In this way, the water temperature of the cooling water does not fall below 0 ° C., so that it is possible to normally cool the water-cooled electric device without breaking the heat exchanger due to freezing.

[0018]

According to the first invention, the cooling water for cooling the electric device, the first pipe for circulating the cooling water in the primary cooling system passing through the electric device, A water cooling pump for circulating the cooling water in the first pipe, a heat exchanger for exchanging heat radiated by the electric device, which is connected to the first pipe, and the heat exchanger radiates heat. The antifreeze liquid is circulated in the secondary cooling system that passes through the antifreeze liquid that is the secondary cooling water for exchanging heat with the generated heat, and the heat exchanger and the cooler that releases the heat absorbed by the antifreeze liquid to the outside air. A second pipe for allowing the antifreeze liquid to circulate in the second pipe, a first temperature detecting means for measuring the temperature of the cooling water passing through the electric device, and an antifreeze liquid A second temperature detecting means for measuring the temperature and giving heat quantity to the cooling water First, a heat quantity is given to the cooling water by the heat source, and the heat quantity is given from the detection result of the cooling water temperature by the first temperature detecting means and the detection result of the antifreeze temperature by the second temperature detecting means. It is determined whether the temperature of the above-mentioned cooling water that has risen due to the above does not freeze even if heat is exchanged with the antifreeze liquid.If the temperature of the cooling water does not freeze, cool the electric equipment. Since the control is performed so as to start, even if heat is exchanged between the antifreeze liquid and the cooling water, the temperature of the antifreeze liquid and the cooling water does not become 0 ° C. or lower, and the cooling can be normally performed.

According to the second aspect of the present invention, the heat source is heat generated during the operation of the water cooling pump, and the control means first starts the water cooling pump to give a quantity of heat to the cooling water, whereby the control means of the first aspect is used. Based on the detection result of the cooling water temperature by the temperature detecting means and the detection result of the antifreezing liquid temperature by the second temperature detecting means, the temperature of the cooling water increased by the heat quantity given from the cooling water pump exchanges heat with the antifreezing liquid. When the temperature of the cooling water does not freeze, the pump is controlled to start the antifreeze pump when the temperature of the cooling water does not freeze. Since the cooling water absorbs the heat from the motor of the water cooling pump, it is possible to store the amount of heat in the cooling water and prevent the heat exchanger from being damaged.

According to the third aspect of the invention, the control means is: T _n : temperature at which cooling water freezes T _F : temperature of antifreeze liquid when starting cooling of electric equipment T _h : cooling water after being heated Temperature T _C : Temperature after heat exchange between the heated cooling water and the antifreeze liquid V ₁ : Volume of the cooling water V ₂ : When the volume of the antifreeze liquid is set, T _h ≧ T _C + V ₂ / V ₁ (T _n − T _F )
Since the control is performed so as to satisfy the condition, even if heat is exchanged between the antifreeze liquid and the cooling water, the temperature of the antifreeze liquid and the cooling water does not become 0 ° C. or less, and the cooling water is circulated in the pipe of the primary cooling system. Can prevent damage to the heat exchanger,
It is possible to reliably cool the electric device.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a cooling device for a water-cooled electric device according to a first embodiment.

FIG. 2 is a diagram showing an operating state of a cooling device for a water-cooled electric device made with the configuration shown in FIG. 1 and respective water temperature changes at that time.

FIG. 3 is a configuration diagram of a cooling device for a conventional water-cooled electric device.

FIG. 4 is a diagram showing an operating state of a cooling device for a conventional water-cooled electric device and water temperature changes at that time.

[Explanation of symbols]

1 water-cooled electric equipment, 2 water-cooled pump, 3
Heat exchanger, 5 surge tanks, 6 pipes, 7
Antifreeze pump, 8 coolers, 9 surge tanks,
10 piping, 20 primary cooling system, 30 secondary cooling system, 40 controller, 41 thermometer, 42 instrumentation cable, 43 control cable, 44 control cable, 51 thermometer, 52 instrumentation cable, 60
Heat source.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hitoshi Teramoto             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. F-term (reference) 3L054 BF01                 3L060 AA01 CC05 CC15 DD08 EE34

Claims (3)

[Claims] 1. A cooling water for cooling an electric device, a first pipe for circulating the cooling water in a primary cooling system passing through the electric device, and a cooling water in the first pipe. A water cooling pump for circulating heat, a heat exchanger connected to the first pipe for exchanging heat dissipated by the electric device, and a heat exchanger for exchanging heat with the heat dissipated by the heat exchanger. A second pipe for circulating the antifreeze liquid in a secondary cooling system passing through an antifreeze liquid which is a secondary cooling water, and a heat exchanger and a cooler for releasing the heat absorbed by the antifreeze liquid to the outside air; An antifreeze pump for circulating the antifreeze in the second pipe, a first temperature detecting means for measuring the temperature of the cooling water passing through the electric device, and a second temperature for measuring the temperature of the antifreeze. First, the detection means and the heat source that gives the heat quantity to the cooling water, The amount of heat is given to the cooling water by the heat source, and the amount of heat is increased by the amount of heat given from the detection result of the cooling water temperature by the first temperature detecting means and the detection result of the antifreeze liquid temperature by the second temperature detecting means. Judge whether the temperature of the cooling water does not freeze even if it exchanges heat with the antifreeze liquid, and if the temperature of the cooling water does not freeze, control to start cooling the electric equipment. Water-cooled electrical equipment characterized by performing. 2. The heat source is heat generated during operation of the water cooling pump, and the control means first starts the water cooling pump to give heat quantity to the cooling water, and the cooling water by the first temperature detecting means. From the temperature detection result and the antifreeze temperature detection result by the second temperature detecting means, the temperature at which the temperature of the cooling water increased by the amount of heat given from the water cooling pump does not freeze even if heat exchange is performed with the antifreeze liquid. The water-cooled electric device according to claim 1, wherein when the temperature of the cooling water does not freeze, control is performed so as to start the antifreeze pump. 3. The control means includes: T _n : temperature at which cooling water freezes T _F : temperature of antifreezing liquid when starting cooling of electric equipment T _h : temperature of cooling water after heating T _C : temperature rising cooling water and antifreeze temperature _V after that heat exchange _1: cooling water capacity _{V 2:} when the volume of _{antifreeze, T h ≧ T C + V} 2 / V 1 (T n -T F) to meet the 3. The water-cooled electric device according to claim 1, wherein the water-cooled electric device is controlled according to claim 1.