JPS5821333Y2 - Cooling system for fully enclosed rotating electrical machines - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a totally enclosed rotating electric machine cooling device.

2. Description of the Related Art Recently, as the trend toward smaller size and larger capacity rotating electrical machines has progressed significantly, the output per unit volume of rotating electrical machines has increased significantly.

The most important problem to be solved here is that of temperature rise.

In other words, as the output per unit volume of a rotating electric machine increases, losses such as iron loss, copper loss, and mechanical loss per unit volume also increase in proportion to the output. The temperature rise value is quite large, and sometimes rises to the limit of the standard value.

In particular, if the temperature rise of the stator coil and rotor coil located inside the rotating electrical machine is large, it will cause early deterioration of the coil insulation and shorten the life of the rotating electrical machine. It is an extremely important issue to improve the effectiveness of cooling the temperature.

In view of the above points, the present invention aims to improve the cooling effect of one or more blower fans fitted to the rotating body by effectively utilizing the space inside the fully enclosed rotating electric machine. .

An embodiment illustrating the present invention will be described below.

1. A conventional ventilation cooling device is constructed as shown in the first figure, in which 1 is a rotor, 2/l'i stator, and 3a.
, 3btj: stator coil, 4: casing, 5a, 5
b is a ventilation guide plate fixed to the casing 4, 6a and 6b are blower fans fitted to the internal rotor shaft, and I is a blower fan fitted to the external rotor shaft.

In the above configuration, when the rotor 1 rotates, the blower fans 6a and 6b rotate and blow the air or refrigerant inside the rotating electrical machine, as shown by the arrows A and 9, respectively, to the stator coil 3a.

3b, a part of which passes through the duct in the stator 2 and reaches the casing 4, transmitting the heat generated inside the rotating electrical machine to the casing 4, and then goes around the outer periphery of the ventilation guide plates 55a and 5b and cools down again. The air is sucked into each of the blower fans 6a and 6b.

Since the air circulating in this way flows through the two paths indicated by the arrow A and the opening, it hardly flows into the space A in the center of the casing 4, which has the disadvantage that the heat cooling effect is poor.

In addition, as shown by arrow C, the blower fan I sucks air from outside the rotating electrical machine and blows it in the axial direction along the fins on the outer circumference of the casing 4, thereby cooling the casing 4 and causing air to be generated inside the rotating electrical machine. It acts to transport heat away to the outside.

Next, the ventilation cooling device according to the present invention is constructed as shown in the second figure, and is basically the same as the conventional device, but the following two points have been improved.

That is, the wind check weirs 8a and 8b are provided at one end of the groove between the internal fins of the casing 4, and the wind regulating ring 9a
, 9b are the stator 2 and the ventilation guide plate 5a.

5b.

These improvements will be explained in more detail.

FIG. 3 is an enlarged partially cross-sectional front view of the casing 4, and FIG. 4 is an expanded view of the inside of the casing 4. There are 48 grooves, divided into 16 groups of 3 grooves each, and wind check weirs 8a are installed alternately at both ends of each group.
, 8b are provided.

Therefore, the cross-sectional area of the groove, that is, the cross-sectional area of the air passage, is the total of the eight groups with the wind check weir 8a installed at the right end, and the total of the eight groups with the wind check weir 8b installed at the left end. are almost equal.

In this way, the grooves between the internal fins of the casing 4 are divided into multiple groups of 2, and wind check weirs 8a are arranged alternately at both ends.
, 8b are provided so that the sum of the cross-sectional areas of the grooves provided with the wind check weir at the right end and the sum of the cross-sectional areas of the grooves provided with the wind check weir at the left end are approximately equal.

Next, as shown in FIG.
Drill 0a.

Although the air conditioning ring 9b is not shown in FIGS. 3 to 5, it has a symmetrical shape to the air conditioning ring 9a, and has a hole 10b at a position corresponding to the wind check weir 8b as shown in FIG.
to be drilled.

In the above configuration, when the rotor 1 rotates, the blower fans 6a and 6b rotate, and the air or refrigerant forced into the blower fan 6a cools the stator coil 3a and flows through the hole 10a of the air conditioning ring 9a to the casing. 4, but it is blocked by the wind check weir 8a, and as shown by the arrow A, it passes through dedicated grooves in groups of three in the embodiment to the left and faces the inner surface of the casing 4. The air flows in the axial direction, goes around the outer periphery of the air guide plate 5b, and is sucked into the air blower fan 6b.

The air or refrigerant forced into the blower fan 6b cools the stator coil 3b and reaches the internal fin portion of the casing 4 through the hole 10b of the air regulating ring 9b.
b, the air flows toward the right through dedicated grooves, which are grouped in groups of three in the embodiment as indicated by the arrows, flows along the inner surface of the casing 4 in the axial direction, and flows around the outer periphery of the wind guide plate 5a. It is sucked into the ventilation fan 6a (see FIG. 4).

The air or refrigerant flowing inside the casing 4 transfers heat generated inside the rotating machine to the casing 4 during this time.

As mentioned above, all ventilation by the ventilation fan 6a must pass through the inside of the casing 4 and be directed to the opposite side by the ventilation fan 6b.
All the ventilation from the blower fan 6b also passes through the inside of the casing 4 and is sucked into the blower fan 6a on the opposite side.

At this time, in the air passage inside the casing 4, the sum of the cross-sectional areas of the grooves indicated by arrow A and the sum of the cross-sectional areas of the grooves indicated by arrow opening are almost equal, so
Circulation is performed smoothly, and the air or refrigerant circulation path is connected in series by two blower fans 6a, 6b to form a single path.

Therefore, in the conventional type, air or refrigerant hardly flows through the casing internal space A, but in the device of the present invention, the entire air or refrigerant passes through the casing internal space A and is cooled.

Note that, like the conventional type, the blower fan 7 sucks air from outside the rotating electric machine, and blows air into the casing 4 as shown by arrow C.
Air is blown in the axial direction along the fins on the outer periphery of the rotary electric machine to cool the casing 4 and carry away the heat generated inside the rotating electric machine to the outside.

In the case of this embodiment, as in the conventional case, the blower fan 7 sucks in air from outside the rotating electrical machine and blows the air in the axial direction along the fins on the outer circumference of the casing 4, as shown by arrow C. , which functions to cool the casing 4 and carry away the heat generated inside the rotating electric machine to the outside.

As an experimental example of a rotating electric machine according to the present invention, a squirrel-cage Sanwa induction motor of 290KW, 2P, voltage 6KV was used.

An experiment was conducted under extremely poor cooling conditions for type 1 insulation, and while a conventional electric motor had a temperature rise of 100°C, the cooling device of the present invention was able to suppress the temperature rise to approximately 80°C.

The cooling device of the present invention has a simple configuration and forms a single ventilation path inside the rotating machine, so compared to conventional types, the heat exchange area increases as the axial length increases. , when comparing this embodiment with the conventional example shown in the first diagram,
The heat exchange area can be increased by about 50 to 100%,
It has the excellent advantage of being able to significantly improve the cooling effect.

[Brief explanation of drawings]

Figure 1 is a partially sectional side view showing a conventional ventilation system path;
The figure is a partial cross-sectional side view showing the ventilation system path of the present invention, Figure 3 is a partial cross-sectional front view showing an enlarged view of the casing, Figure 4 is a partial exploded view of the casing, and Figure 5 is a partial cross-sectional view showing the ventilation ring. In the drawings, A is a half-sectional front view of the upper half, the mouth is a cross-sectional side view of the upper half, and C is a partial plan view. 6a, 6b...Blower fan, I...
・Blower fan, 8a, 8b... Wind check weir, 9
a, 9b... Wind adjustment ring.

Claims (1)

[Claims for Utility Model Registration] In a totally enclosed rotating electric machine in which one or more blower fans are fitted to the internal rotating body, the grooves between the internal fins of the casing 4 are divided into multiple groups of multiples of 2. Wind check weirs 8a are installed at both ends alternately for each group. 8b is provided so that the sum of the cross-sectional areas of the valley grooves with the wind check weir 8a provided on the right end and the sum of the cross-sectional areas of the valley grooves with the wind check weir 8b provided on the left end are approximately equal. , holes 10a at positions corresponding to the wind check weirs 8a and 8b,
Two air conditioning rings 9a and 9b with holes 10b are provided,
Air or refrigerant forced into the blower fan 6a fitted to one end of the rotating body passes through the hole 10a of one air conditioning ring 9a, flows axially through the groove between the internal fins of the casing 4, and reaches the other end of the rotating body. reach the other air straightening ring 9 in the opposite direction.
A ventilation path inside the totally enclosed rotating electric machine is constructed so that the air flows in the axial direction through the hole 10b of b, through the groove between the internal fins of the casing 4, which is different from the outgoing path, and is sucked into the blower fan 6a again. 1. A cooling device for a completely enclosed rotating electric machine, characterized in that the cooling device is formed to form a channel.