JPH0674188A - Electronic fan - Google Patents

Abstract

PURPOSE:To provide an electric fan where a blower for a main electric motor can be reduced in size and weight. CONSTITUTION:An electric fan is provided with a frequency pattern generator 2 of an electric motor for an electric fan according to variation of a static pressure with respect to a speed of a main electric motor for a vehicle and variation of a static pressure due to traveling wind, and an inverter device 4 for inputting a speed signal 1 of the main electric motor for a vehicle into the frequency pattern generator 2 so as to generate a frequency and a voltage corresponding to the frequency output from the frequency pattern generator 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric blower device for a vehicle main motor (hereinafter referred to as a main motor).

[0002]

2. Description of the Related Art In recent years, railway vehicles have been desired to be small and lightweight for high speed operation, and electric blowers for main motors (hereinafter referred to as blowers) are also desired to be small and lightweight without exception.

FIG. 4 shows an example of the configuration of a conventional blower device. In the conventional blower for the main motor, an induction motor is used for the blower motor 8 (hereinafter referred to as a blower motor),
It is rotated at a constant speed by an AC power source 7 having a constant frequency, generates a constant amount of cooling air, and supplies it to a main motor (not shown). However, in general, as the rotation speed of the main motor increases, the resistance to the cooling wind inside the main motor and the resistance to the traveling wind (hereinafter collectively referred to as “Head Loss”).
s ”) and the blower is trying to supply a constant amount of cooling air to the traction motor, but due to an increase in the head loss of the traction motor, the amount of cooling air flowing into the traction motor is increased. Decreases as the rotation speed of increases. Here, the relationship between the rotation speed of the main motor and the head loss of the main motor is shown in FIG. 5, and the relationship between the rotation speed of the main motor and the cooling air flow flowing into the main motor is shown in FIG.

The blower needs to supply the rated cooling air volume of the traction motor at any rotation speed from the start-up of the traction motor to the maximum normal rotation speed. So the head of the main motor
The output of the blower motor 8 is determined so that the cooling air flow rate becomes the main motor rated cooling air flow rate at the rotation speed at which Loss becomes maximum, generally at the normal maximum rotation speed.

[0005]

Head of the traction motor
Since the output of the blower motor 8 is set at the maximum Loss, when the rotation speed of the main motor is low, the Hea
The dLoss is small, and the cooling air volume that exceeds the rated cooling air volume of the main motor flows in the main motor. It is not necessary for the main motor to exceed the rated cooling air volume, and when the main motor rotates at low speed, the blower generates more cooling air volume than necessary, so the blower motor 8
Current increases. Considering that the train is stopped, the rated current of the blower motor 8 needs to be determined in consideration of this increase, so an output larger than necessary is required, and the blower body takes into consideration the high Head Loss during high-speed running. It is extremely large and uneconomical because it needs to be enlarged. SUMMARY OF THE INVENTION It is an object of the present invention to provide an electric blower device capable of reducing the size and weight of a blower for a main motor.

[0006]

In order to achieve the above object, the invention according to claim 1 is for an electric blower capable of responding to a change in static pressure with respect to the speed of a vehicle main motor and a change in static pressure due to running wind. An electric blower device comprising a frequency pattern generator of an electric motor and an inverter device for inputting a speed signal of the vehicle main electric motor to the frequency pattern generator and generating a frequency and a voltage corresponding to a frequency output from the frequency pattern generator. is there.

[0007]

In the invention according to claim 1, when the main electric motor is stopped or rotates at a low speed, the main electric motor He corresponding to the rotation speed is provided.
Since the frequency and voltage that generate ad Loss are supplied to the blower motor, the rated air volume can be passed without an excessive current flowing, and if the train speed increases, the frequency pattern setter will give a predetermined static to the speed signal. Since the blower motor is driven by the frequency that generates pressure, it is not necessary to make the blower body larger than necessary, and the blower device can be made compact and lightweight.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the schematic construction of the blower motor driving inverter 4 driven by a DC power source 3.
The blower motor driving inverter 4 drives the blower motor 5 and the fan 6 rotates to generate cooling air. Where Head L for the main motor
In consideration of oss, a pattern generator 2 in which the rotation speed of the blower motor 5 is preset so that the air flow into the main motor becomes the main motor rated air flow is provided, and the speed signal 1 of the main motor is supplied to the pattern generator 2. Blower motor drive inverter 4 by inputting and output f of pattern generator 2
To drive. FIG. 2 shows a pattern generated by the pattern generator 2.

The blower motor 5 rotates at a rotation speed corresponding to the rotation speed of the main electric motor, that is, in consideration of the relationship between the rotation speed of the main electric motor and the head loss of the main electric motor, and the blower is always rated by the main electric motor. The cooling air volume is generated so that the cooling air volume flows in. As a result, the main motor rated cooling air volume flows inside the main motor at any rotation speed of the main motor.

When the frequency of the blower motor 5 is controlled by the speed signal of the main motor, the relationship between the rotation speed of the main motor and the input current B of the blower motor 5 and the conventional blower motor 8
The relationship between the rotation speed of the main motor and the input current A of the blower motor 8 is shown in FIG. Comparing the input current of the blower motor 5 when the frequency is controlled in FIG. 3 with the current of the conventional blower motor 8, the current when the frequency is controlled becomes the maximum at the maximum speed.
However, in the case of the conventional blower motor 8, the maximum current is in the low speed range from the start, and considering that the train has been stopped for a long time, the maximum current determines the rated capacity of the blower motor. There is a need. Therefore,
In the present embodiment, a blower motor having a small capacity corresponding to the amount of current decrease ΔI can be used, and not only the blower device can be made compact and lightweight, but also the rotation speed of the blower is reduced while the vehicle is stopped, resulting in low noise. Can be achieved.

By controlling the output frequency f of the blower motor driving inverter 4 by the speed signal of the main motor,
The amount of cooling air flowing into the main motor can always be set to the rated amount of cooling air. When comparing the maximum input currents of the blower motor 5 and the conventional type blower motor 8 which have been controlled in this way, the former is smaller and the output is smaller. Can be smaller,
Since the blower motor 5 can be made smaller and lighter, that is, the blower can be made smaller and lighter, and the frequency when the vehicle is stopped can be lowered.
It is possible to reduce noise when the train is stopped. The present invention is not limited to the embodiments described above, but may be as follows, for example.

That is, the Head Loss of the main motor
If the blower motor input current frequency f is controlled by the speed signal of the main motor so that the rated cooling air volume of the main motor flows into the main motor only when the rotation speed becomes large, the main motor can be operated at almost any speed. An air flow rate close to the rated cooling air flow rate of the above flows into the main motor. Even when the head loss of the main motor becomes large and the rotation speed of the blower motor is controlled only when the rotation speed is high, the same effect as that of the above-described embodiment can be obtained, and the blower can be downsized and reduced in weight and noise can be reduced.

[0014]

According to the present invention, it is possible to provide an electric blower device capable of reducing the size and weight of a blower for a main motor.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a main motor rotation speed and a blower motor input frequency f according to FIG.

FIG. 3 is a diagram showing the relationship between the rotation speed of the main motor of FIG. 1 and the input current of a blower motor.

FIG. 4 is a block diagram showing a conventional example.

FIG. 5 is a main motor rotation speed and a head loss of FIG.
FIG.

FIG. 6 is a diagram showing the relationship between the conventional main motor rotation speed and the air volume flowing into the main motor shown in FIG. 4;

[Explanation of symbols]

1 ... Vehicle main motor speed signal, 2 ... blower motor input frequency f pattern generator, 3 ... DC power source, 4 ... blower motor driving inverter, 5 ... blower motor, 6 ... fan,

Claims (1)

[Claims] 1. A frequency pattern generator of a motor for an electric blower corresponding to a change in static pressure with respect to a speed of a vehicle main motor and a change in static pressure due to traveling wind, and a speed signal of the vehicle main motor for the frequency pattern. An electric blower device having an inverter device for generating a frequency and a voltage corresponding to a frequency input to and output from a generator.