JPH0837761A - Drying and condensation prevention device for rotating electric machine - Google Patents

Abstract

(57) [Abstract] [Purpose] To reduce both the relative and absolute humidity of the air inside a large rotating electric machine. [Structure] Connected to the intake side and the return side at both axial ends of a rotating electric machine via pipes, a blower 2, a dehumidifier 3, and a heater 4.
Switch 8 for turning the heater 4 on and off, temperature sensors 5 and 6 for detecting the air temperature on the return side and the air temperature on the intake side, and inputting signals from the temperature sensors 5 and 6 to the switch 8. It is composed of a controller 7 that sends an on / off signal, and circulates air to remove moisture,
Since the air temperature on the return side is heated to be higher than the air temperature on the intake side, both the relative humidity and the absolute humidity of the air inside the machine are reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drying and condensation preventing device for a large rotating electric machine.

[0002]

2. Description of the Related Art If the temperature inside a rotating electric machine falls below the dew point of internal air when the operation of the rotating electric machine is stopped, dew is tied in the machine and this is not preferable for the insulation of the windings. Space heater (hereinafter referred to as heater)
Is provided. The heaters are attached to the bottoms of both ends of the rotating electric machine in the axial direction. The inside of the machine is heated by the radiation from the heater and the convection of the air inside the machine. Although the heater is designed to raise the temperature inside the machine by 5 ° C. or more with respect to the outside air temperature, the installation location is often limited due to restrictions on the internal structure of the machine. That is, in order to maintain the temperature of the required portion at 5 ° C. or higher, it is necessary to provide a large-capacity heater or to limit the temperature rise of the portion close to the heater.

[0003]

The heater installed inside the machine raises the temperature of the air inside the machine and lowers the relative humidity, but the absolute humidity does not drop because moisture is not removed. The relative humidity is a value that represents the percentage of the saturated vapor pressure at that temperature of the partial pressure of water vapor in the air, and the absolute humidity is the amount (kg) of water vapor contained in 1 kg of dry air. If the dust accumulated in the machine absorbs moisture over time, the air inside the machine cannot be sufficiently dried only by the effect of the temperature increase by the heater. Therefore, in a large rotating machine such as a turbine generator, the insulation resistance of the rotor winding is reduced, and even if the air heated by the heater is circulated in the machine with a blower for a long time, the insulation resistance value specified by JIS is achieved. It is experienced that it is not done.

An object of the present invention is to provide a drying and condensation preventing device for a rotary electric machine, which reduces both the relative humidity and the absolute humidity of the air inside the large rotary electric machine.

[0005]

A blower, a dehumidifier, a heater, and a switch for turning on / off the power of the heater, which are connected to the intake side and the return side at both axial ends of a rotating electric machine through pipes. , The temperature sensor for detecting the air temperature on the return side and the air temperature on the intake side, and a controller for inputting a signal from the temperature sensor and for inputting an ON / OFF signal to the switch. To achieve.

Further, the controller compares the signal from the temperature sensor for detecting the air temperature on the return side with the signal from the temperature sensor for detecting the air temperature on the intake side, and issues an ON / OFF signal to the switch according to a predetermined condition. This is suitable for removing moisture inside the machine.

[0007]

According to the present invention, a blower for circulating the air inside the machine, a dehumidifier connected in series to the blower, a heater, a switch for turning the heater on and off, a temperature sensor, an intake side and a return side. The device consists of a controller that inputs the temperature detected by the temperature sensor on the side and enters the heater under the specified conditions and sends a cutoff signal. The air inside the machine is dehumidified by the dehumidifier and heated by the heater. Since the air whose temperature is higher than the temperature on the intake side is returned to the inside of the machine as return air, it is possible to reduce the relative humidity of the inside air and the absolute humidity, and prevent the condensation while drying the inside air.

[0008]

Embodiment 1 FIG. 1 is a system diagram of a drying and dew condensation preventing apparatus provided with a refrigerating dehumidifier of the present invention. Valves 1 are provided at both axial ends of the rotating electric machine 1.
2 and 14 and a circulation path connected via piping are formed. The valves 12 and 14 are closed during the operation of the rotating electric machine 1. The circulation path is a blower 2, a refrigerating dehumidifier 3, and a heater 4.
And the temperature sensor 5, 6 and the controller 7 for inputting the signal from the temperature sensor 5, 6 to the switch 8 and sending the off signal. The valve 1 when the rotating electric machine 1 is at rest
2, 2 and 14 are opened, the humidity of the air sent from the inside of the machine by the blower 2 is removed by the refrigerating dehumidifier 3, and the heater 4
The air heated by is circulated into the machine. The refrigeration dehumidifier removes moisture by exchanging heat with the air to be dehumidified. The temperature sensor 5 detects the air temperature on the return side sent from the heater 4, and the temperature sensor 6 detects the air temperature on the intake side and inputs it to the controller 7. The controller 7 controls the return side air temperature to be higher than the intake side air temperature.
Turn on switch 8 and send off signal. It is effective to keep the humidity inside the machine at about 5 ° C or less at the dew point in order to prevent condensation. When the rotary electric machine 1 is operated, the valves 12 and 14 are opened, the heater 4 is turned off, and the air inside the machine is circulated by the blower 2 to have a dehumidifying function.

Embodiment 2 FIG. 2 is a system diagram of a drying and condensation preventing apparatus equipped with the gel type dehumidifier of the present invention. During operation of the rotary electric machine 1, the valve 12,
14 is closed. The circulation path is a blower 2, a heater 4,
It is composed of a gel type dehumidifier 9, temperature sensors 5 and 6, and a controller 7 for inputting signals from the temperature sensors 5 and 6 and turning on and off a switch 8. When air is circulated when the rotary electric machine is at rest, the valves 11 and 13 are opened,
The air sucked from the inside of the machine by the blower 2 is heated by the heater 4, dehumidified by the gel type dehumidifier 9, and circulated in the machine. The temperature sensor 5 measures the temperature of the return air sent from the heater 4.
The temperature of the intake air is detected by the temperature sensor 6 and input to the controller 7. The controller 7 sends an ON / OFF signal to the switch 8 so that the return side air temperature becomes higher than the intake side air temperature. When regenerating the gel of the gel type dehumidifier 9, the valves 12 and 14 are closed, the valves 11 and 13 are opened, the air sucked by the blower 2 through the ilter 10 is heated by the heater 4, and the high temperature air is dehumidified by the gel type dehumidifier. The gel is dried and regenerated while being evacuated from the feed valve 13 to the container 9. In operating this device, when drying the inside of the machine, lower the temperature of the heater 4 to circulate air,
When regenerating the gel of the gel type dehumidifier 9, the temperature of the heater 4 is raised. It is effective to keep the humidity inside the machine at about 5 ° C or less at the dew point in order to prevent condensation. When the rotary electric machine 1 is operated, the valves 12 and 14 are opened, the heater 4 is turned off, and the air inside the machine is circulated by the blower 2 to have a dehumidifying function.

[0010]

According to the present invention, the blower, the dehumidifier, the heater, the temperature sensor, and the controller are connected to both ends in the axial direction of the rotating electric machine to form a device, and the air temperature on the intake side and the return side. The air temperature on the return side is made higher than the air temperature on the intake side by turning on / off the heater according to the signal from the controller according to the specified conditions by comparing the air temperature of In addition, since it is dehumidified, it is possible to reduce both the absolute humidity and the relative humidity of the air inside the machine. As a result, the air inside the machine is sufficiently dried, and the dust accumulated in the machine does not become moist over the years, and the insulation resistance of the rotating electric machine can be maintained at the specified value.

[Brief description of drawings]

FIG. 1 is a system diagram of a drying and condensation preventing device for a rotary electric machine according to a first embodiment of the present invention.

FIG. 2 is a system diagram of a drying and condensation preventing device for a rotary electric machine according to a second embodiment of the present invention.

[Explanation of symbols]

 1 Rotating Electric Machine 2 Blower 3 Refrigeration Dehumidifier 4 Heater 5 Temperature Sensor 6 Temperature Sensor 7 Controller 8 Switch 9 Gel Dehumidifier

Claims (2)

[Claims] 1. A blower, a dehumidifier, a heater, a switch for turning on / off the power of the heater, and the return side, which are connected to the intake side and the return side at both axial ends of a rotating electric machine through pipes. And a temperature sensor for detecting the air temperature on the intake side, and a controller for inputting a signal from the temperature sensor and inputting a switch signal to the switch, and a drying signal for a rotary electric machine, Dew condensation prevention device. 2. The drying and condensation preventing device for a rotating electric machine according to claim 1, wherein the controller outputs a signal from a temperature sensor that detects an air temperature on the return side and a signal from a temperature sensor that detects an air temperature on the intake side. And a drying / condensing prevention device for a rotating electric machine, characterized by transmitting an ON / OFF signal to a switch according to predetermined conditions.