JPH0360543B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) This invention aims to protect high-voltage insulators used in electrostatic equipment such as electrostatic precipitators, by preventing condensation on the insulators and preventing dust from adhering to the inner surface of the insulators. This invention relates to a method for controlling the atmosphere inside an insulator, which performs hot air purging.

(Prior art) Conventionally, the protection of high-voltage insulators (hereinafter simply referred to as insulators) in electrostatic precipitators was to keep them warm with the main purpose of preventing condensation. Warm air at 90°C was introduced into the insulator room through a duct pipe and blown into the room to raise and maintain the room temperature of the insulator.

This hot air generator is designed with a large heater capacity and blower airflow capacity, taking into consideration the need for early temperature rise after restarting operations due to periodic repairs, etc., and to prevent clogging of the filter in the air intake port. There was a tendency to use one with a large capacity.

(Problems to be Solved by the Invention) The method for keeping an insulator warm using the above-mentioned hot air generator has the following problems.

(1) Minimum temperature regardless of ambient temperature (outside temperature)
It is an on-off operation with a maximum temperature of 80℃ and a maximum temperature of 90℃.
Power consumption is high.

(2) Since there is no air volume control device, the air volume is increased to prevent filter clogging, which wastes electricity.

(3) Even if the filter becomes clogged and the air volume decreases significantly, this fact cannot be confirmed.

In view of these problems, the present invention achieves the original purpose of preventing condensation on the insulator while controlling the hot air temperature to a low temperature and the amount of hot air to reduce the heating power of the hot air generator and the power of the blower. The purpose of this invention is to provide a control method that allows

(Means for Solving the Problems) The present invention controls the temperature of hot air blown into the insulator chamber to a certain temperature higher than the outside air temperature, and controls the flow rate of hot air to a rate that prevents dust from diffusing and rising on the inner surface of the insulator. This is a method for controlling the atmosphere in an insulator room.

(Function) Hereinafter, the function of the present invention will be explained in detail based on the drawings.

Figure 1 shows an overview of the insulator room air temperature and air volume control device. In the figure, reference numeral 1 indicates an outside air intake port, which is provided with a dust prevention filter. 2 is an electric blower for blowing hot air; 5 is a motor for rotating the blower 2; 3 is a heater for heating the outside air; 4 is an air volume adjustment valve provided in the duct pipe 10; 6 is a measuring device for measuring the temperature of the hot air blown into the insulator chamber. temperature sensor, 7
is the insulator chamber, 8 is the insulator, 8a is the opening of the insulator 8, 8
b is an electrode hanging rod, 9 is an electric precipitator, 10 is a duct pipe that guides cold air or temperature, 10a is a duct branch pipe that leads temperature to each insulator chamber, 11 is a variable voltage controller for controlling heater current, 12 is a PID Temperature controller, 13 is outside temperature measuring device, 15 is measuring device 1
3 a temperature signal converter that changes the measured value by +α°C, 14 a sensor for measuring the volume of hot air provided in the duct pipe 10, 16 an air volume regulator, 17 an air volume setting device, 19
2 is an air volume regulating valve driving device, and 20 is an air volume signal converter.

A heater 3, a temperature sensor 6, a variable voltage controller 11, a PID temperature controller 12, an outside air temperature measuring device 13, and a temperature signal converter 15 constitute a hot air temperature control means, and further include an air volume adjustment valve 4 and an air volume measurement sensor. 14, the air volume controller 16, the air volume setting device 17, the air volume adjustment valve driving device 19, and the air volume signal converter 20 constitute a hot air volume control means. Although not shown,
A plurality of branch pipes 10a extend from a duct pipe 10 on the outlet side of the heater 3, and each branch pipe 10a is connected to a plurality of insulator chambers 7. The temperature sensor 6 and the air volume measurement sensor 14 are provided in one typical branch pipe 10a.

The temperature of the hot air is controlled by detecting the actual temperature of the hot air with a temperature sensor 6 installed near the insulator chamber of the duct branch pipe 10a, and inputting this detection signal to the feedback signal of the PID temperature controller 12. On the other hand, the outside air (atmosphere) temperature is measured by the outside air temperature measuring device 13, and after level conversion by the temperature signal converter 15 to a signal level corresponding to the outside air temperature plus α°C, the temperature reference input to the PID temperature controller 12 is performed. Input as a signal.
The input signals are compared in the PID temperature controller 12,
The output based on the difference forms a feedback temperature control system which serves as an input signal to a variable voltage controller 11 for controlling the current of the heater 3. This hot air temperature control means controls the temperature of the hot air blown into the insulator chamber 7 to a constant temperature of the outside air temperature plus α°C.
If the plus α°C is set above the dew point temperature of the blown gas, there is no risk of condensation on the insulator surface, but it is preferably within the range of +20°C to 30°C above the outside air temperature, and should be set around +20°C from the point of view of power saving. is preferred.

On the other hand, in order to control the amount of warm air, hot air is blown into the electrostatic precipitator 9 from the insulator chamber 7 through the opening 8a at the top of the insulator 8 so that the dust in the dust collector 9 does not adhere to the inner surface of the insulator. The flow velocity must be set to a flow rate higher than the velocity at which the dust inside the electrostatic precipitator 9 diffuses and rises to the inner surface of the insulator.

It is also necessary to ensure the air volume necessary to raise the temperature of the insulator before the dust collector is in operation and to keep the insulator warm after the dust collector is in operation. The insulator chamber 7 of the duct branch pipe 10a constituting the air volume control means satisfies these objectives.
The air volume is detected by an air volume measurement sensor 14 provided near the air volume, and an air volume signal converter 20 converts the air volume into a voltage level signal and inputs the voltage level signal to the air volume controller 16. Also,
The set air volume Q (the air volume that is higher than the speed at which the dust inside the dust collector 9 does not rise to the insulator chamber 7) is input from the air volume setting device 17, and the air volume adjustment valve is controlled via the air volume adjustment valve drive device 19 so that the air volume Q is achieved. Controls the opening degree of 4.

The set air volume Q is increased when the insulator is heated up before operation (adjusting valve 4 is fully opened), and when kept warm after operation.
It is preferable to perform constant control at an air flow rate higher than the speed at which the dust inside the electrostatic precipitator does not diffuse and rise. It was found that the internal pressure of the dust collector during operation was about -2000 mmAq, and that the blowing speed into the dust collector did not increase if it was 0.1 m/s or higher. Look at safety,
It is preferable to set the air volume Q in the range of 0.0 to 0.2 m/s.

According to this air volume control means, even if a factor that changes the air volume occurs, such as clogging of the filter of the outside air intake port 1, a small amount of air volume can be ensured, and the power consumption of the blower device can be saved. Additionally, if it becomes difficult to secure the required air volume due to filter clogging, a warning display (not shown) will be displayed.
It is also possible to contact the operator.

(Example) The indoor atmosphere of insulators was controlled for a total of 48 insulators (2 to 3 insulators are provided in each room) in 20 insulator chambers attached to a dust collector. outside temperature 10
℃, the hot air temperature was set to outside air temperature + 20℃, and the flow rate of hot air to the dust collector was set to 0.1 m/s. The air volume has increased from 300m ² /m to 180m ³ /m.
Heater power consumption increased from 360Kw to 160Kw.
A power saving of 200Kw was achieved.

(Effects of the Invention) As explained above, according to the present invention, by controlling the temperature of warm air that does not cause dew condensation on the insulator at a constant level of outside air temperature + α℃, the temperature that was conventionally controlled at 80 to 90℃ can be increased throughout the year. can also be controlled within the range of 20 to 50℃,
By controlling the air flow to the minimum flow rate that prevents dust from rising inside the dust collector, significant power savings can be achieved in heater power and blower power. Furthermore, when new equipment is installed, a blower and a heater with a smaller capacity than conventional equipment can be used, which has excellent effects such as lower equipment costs.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an outline of an insulator room air temperature and air volume control device. 1...Outside air suction port, 2...Electric blower for blowing hot air, 3...Heater for heating outside air, 4...Air volume adjustment valve, 5...Motor, 6...Temperature sensor, 7...Insulator chamber, 8...Insulator, 8a... Opening part of insulator 8, 8b... Electrode hanging rod, 9... Electrostatic precipitator, 10... Duct pipe, 10a... Duct branch pipe, 11... Variable voltage controller, 12... PID temperature controller, 13... Outside air temperature measuring device, 14... Hot air volume measurement sensor, 15... Temperature signal converter, 16... Air volume regulator, 17... Air volume setting device, 19... Air volume adjustment valve drive device, 20... Air volume signal converter.

Claims (1)

[Claims] 1. A method for controlling the atmosphere in an insulator chamber, characterized by controlling the temperature of hot air blown into the insulator chamber to a certain temperature higher than the outside air temperature, and controlling the flow rate of hot air to a rate at which dust does not diffuse and rise inside the insulator.