JP2715546B2 - Winding device for current conductor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention forcibly wind-cools a current conductor such as a phase-separated bus of a power plant by alternately operating a commercial and a standby electric blower. And a device for the same.

[Prior Art] FIG. 2 is a schematic configuration diagram showing a conventional current conductor air cooling device disclosed in Japanese Patent Application Laid-Open No. 61-229997, for example, showing the operating state of a commercial electric blower. A case where the phase separation bus as a current conductor is cooled will be described.

In FIG. 2, reference numerals 1 and 2 denote ordinary and standby electric blowers which are operated alternately.
Is for blowing cooling air to the phase separation bus 11 through the ventilation duct 12 to cool the conductor 11a of the phase separation bus 11 described later to create a circulating flow.
Motors for driving 1, 2; 5, a pipe for diverting cooling air to the service electric blower 1 during operation of the service electric blower 2; and 6, a cooling air to the protection electric blower 2 during operation of the service electric blower 1 (second cooling air). 7 is a duct for sending the cooling air from each of the electric blowers 1 and 2 in a predetermined direction;
8 is an air path switching damper for switching the supply side air path, 9 is a generator (G), 10 is a main transformer, and 11 is a phase separation bus connecting these generators 9 and the main transformer 10. .

Next, the operation will be described. One of the electric blowers 1 or 2 is driven by the motor 3 or 4, and the ventilation duct
Cooling air is sent to the conductor 11 a of the phase separation bus 11 via the connection 12. Regardless of which one of the electric blowers 1 or 2 is operating, a part of the cooling air formed by the air passage switching damper 8 through the pipe 6 or 5 causes the other electric blower 2 or It is led to 1.

As a result, the electric blower 1 or 2 in the standby state continues to rotate at a low speed, and as described in the above-mentioned publication, the drive unit of the electric blower 1 or 2 in the stopped state is damaged or the like. Can be prevented.

[Problems to be Solved by the Invention] The conventional current conductor air cooling device is configured as described above, and the cooling air to the phase separation bus 11 is In order to secure a sufficient amount, the amount of air in the diverted stream must be increased, and there is a problem that a large amount of energy is wasted.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and enables an electric blower in a standby state to be maintained in a stable and economical low-speed rotation state without performing a flow split of an air flow, so that an electric blower in operation can be maintained. It is an object of the present invention to provide an air blower for a current conductor, which realizes energy saving of a blower and has high reliability without causing damage to a drive unit of an electric blower.

[Means for Solving the Problems] A current conductor wind-cooling device according to the present invention comprises a current detecting means for detecting a value of a current flowing through the current conductor, and an operation of each electric blower based on a detection result from the current detecting means. Inverter devices serially interposed in the power supply circuit of the service electric blower and the power supply circuit of the backup electric blower to control the state, and one of the electric blowers in the standby state among the electric blowers is controlled by the inverter device. It has a control circuit for driving at low speed rotation.

[Operation] In the current conductor wind-cooling device according to the present invention, the operating electric blower is operated at a variable speed by the inverter device in accordance with the value of the current flowing through the current conductor detected by the current detecting means, while the electric blower is on standby. The electric blower is controlled by the control circuit
It is always driven to rotate at a low speed by the inverter device.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram showing a current conductor air cooling device according to an embodiment of the present invention. In the figure, the same reference numerals as those described above denote the same parts, and a description thereof will be omitted. . Also in the present embodiment, a case where the phase-separated bus as a current conductor is cooled will be described. FIG. 1 shows the operating state of the commercial electric blower.

In FIG. 1, 13 is a current transformer (current detecting means) for detecting a circuit current value flowing through the conductor 11a, and 14 is electrically connected to the current transformer 13 and outputs a current detection signal to a predetermined control signal. Convert to transducer, 15 is transducer
An inverter device (not shown) serially interposed in a power supply circuit (not shown) of the electric blower 1 in order to operate the service electric blower 1 at a variable speed based on the control signal from 14 and control the discharge air volume to a necessary minimum. INV) and 16 are inverter devices (INV) provided in a power supply circuit (not shown) of the spare electric blower 2 for the same purpose as the inverter device 15, and 17 is an inverter device which is in standby state. A control circuit for low-speed rotation drive by 15 or 16 and 18a and 18b are changeover switches for switching and connecting control signals from the transducer 14 and the control device 17 to one of the inverter devices 15 and 16, respectively.

Next, the operation of the device of the present embodiment will be described. The circuit current value of the conductor 11a from the current transformer 13 is
After being converted into a predetermined control signal in 4, the signal is sent to the inverter device 15 or 16 via the changeover switch 18a, and either one of the inverter device 15 or 16 is used to control the normal electric blower 1 or the standby electric blower 2. Either one is operated at a variable speed.

On the other hand, the electric blower 2 or 1 on standby, which does not receive the control signal from the transducer 14, is provided with a changeover switch.
The inverter 16 or 15 that receives a control signal from the control circuit 17 via 18b constantly rotates at low speed during standby.

Generally, the required output of the motors 3 and 4 in the electric blowers 1 and 2 is proportional to the third power of the motor rotation speed.
If the low speed rotation of 10Hz is performed for the operation of Hz, (10/60)
An output of ³ × 100 ≒ 0.5% is sufficient, and power consumption is extremely low. Therefore, it is economical to rotate the electric blower 1 or 2 in the standby state at a low speed by the inverter device 15 or 16.

As described above, according to the apparatus of the present embodiment, the operating electric blower 1 or 2 is connected to the conductor 11 a detected by the current transformer 13.
In response to the value of the current flowing through the inverter, the inverter device 15 or 16 is operated at a variable speed, while the electric blower 2 or 1 in a standby state is constantly driven to rotate at a low speed by the inverter device 16 or 15 by the control circuit 17. As described above, the electric blower 2 or 1 in the standby state can be maintained in a stable and economical low-speed rotation state without performing the air flow diverting as in the related art, and the energy saving of the electric blower 1 or 2 in operation can be realized. A highly reliable device that can prevent damage to the drive unit and the like of the electric blower 2 or 1 that has been on standby for a long period of time can be obtained.

In the above embodiment, the air-cooling device for the phase separation bus 11 has been described.However, the present invention is not limited to this. An effect similar to that of the embodiment is obtained. In the above embodiment, the closed circulation type cooling air passage is used. However, an open cooling air passage may be used. In this case, the same effect as in the above embodiment can be obtained.

[Effects of the Invention] As described above, according to the present invention, the operating electric blower is operated at a variable speed by the inverter according to the current value of the current conductor from the current detecting means, while the electric blower in the standby state is operated. The control circuit is configured to always rotate at low speed with the inverter device, so that energy saving of the electric blower during operation can be realized, and stable and economical low-speed rotation can be achieved for the electric blower in standby. The state can be maintained, and there is an effect that a highly reliable device that does not cause damage to the driving unit or the like for a long period of time can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a current conductor air cooling device according to an embodiment of the present invention, and FIG. 2 is a schematic configuration diagram showing a conventional current conductor air cooling device. In the figure, 1 ... a regular electric blower, 2 ... a spare electric blower, 11a ... conductor, 13 ... current transformer (current detecting means), 15, 16 ... inverter device, 17 ... control circuit. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

(57) [Claims] 1. A current conductor air-cooling device comprising a regular electric fan and a backup electric fan for blowing cooling air to the current conductor in order to air-cool the current conductor, wherein a current value flowing through the current conductor is detected. And a power supply circuit of the service electric blower and a power supply circuit of the backup electric blower connected in series to control the operation state of each electric blower based on the detection result from the current detection means. And a control circuit for driving one of the electric blowers, which is in standby, among the electric blowers at a low speed by the inverter device. .