SU141928A1 - Device for ventilation of synchronous motors - Google Patents

Description

Devices are known for ventilating synchronous electrodes, in which cold air is pumped into the chamber between the machine body and the stator back and passes through the radial channels and the machine gap into the interpolar rotor channels.

In contrast to the known, in order to improve the cooling of the machine, a centrifugal fan (vent compensator) attached to the rotor is used to compensate for the rotor's influence on the movement of air from the stator, thereby providing the required aerodynamic characteristics of the ventilation network. To create a radial-axial air-air displacement in opposite directions, two vent compensators are used, located at both ends of the rotor. To create a counter axial-radial ventilation system, one vent compensator is used, located at one end of the rotor. In the case of using a synchronous motor for drives with a flywheel, the vent compensator is located on the inner end side of the flywheel and is also used to force air into the chamber between the housing and the backrest of the stator. The devices described above are used in self-ventilation or forced ventilation systems of synchronous motors.

FIG. 1 shows a diagram of an oncoming radial ventilation system; in fig. 2 is a diagram of axial-radial counter ventilation; in fig. 3 -. a scheme for supplying air to the chamber of the stator housing during counter-forced ventilation; in fig. 4 is a diagram of a self-ventilating machine with a counter axial-radial ventilation system and with a high-pressure fan; in fig. 5 is a schematic of a self-ventilation of a skinny machine with counter axial-radial ventilation and with a fan located on the flywheel.

№ 144528 2

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For cooling synchronous electric motors, both self-ventilating; Xe, as well. Kryugztelnaya air supply from outside fan 1, located outside the machine, mainly uses radial and axial-radial ventilation systems. At the same time, the cooling air action of pressure developed by pressure elbmes - machines - fans and rotor 2 passes through the interpolar rotor windows and flows from the gap into the radial channels of the stator 3 and further to the back of the stator, cooling the core and the winding groove. At the same time, the part emerging from the fans cools the frontal connections 4 and also extends over the back of the stator. In low-speed synchronous motors, the cooling performed according to this scheme is not enough; therefore, the overheating is overheated, and this leads to premature destruction of the insulation.

In order to dry more efficiently cool the cold air comes not from the ends of the rotor, but from the back of the stator.

With a counter air supply, the stator is a distributed grid-type resistance, and the air is evenly distributed through all the channels of the stator and moves radially towards the gap of the machine. Upon entering the gap, the air is twisted evenly by the rotor poles and, under the action of overpressure from the back of the stator, enters the interpolar windows, from where it is thrown from both sides into the room or under the machine shits. In this case, the rotational speed of the flow decreases, and part of the spin energy is used to create a static pressure acting in the direction of flow.

To ensure the stability of the operation of the ventilation scheme and obtain a normal external aerodynamic characteristics of the meeting, the ventilation scheme is made in two versions:

1) Radial counter (Fig. 1), used for long synchronous motors.

2) An axial-radial counter (Fig. 2) used for short synchronous motors.

In these schemes, the air supplied to the stator housing chamber 5 has a static pressure higher than the static pressure in the gap. When exiting the stator, the flow is divided into two streams; one jet (axial), through the windows in the rack goes into the chamber of the frontal connections and then enters the interpolar windows; the other jet (radial), passing through the radial channels of the stator, enters the gap of the machine and the interpolar windows. In this scheme, as in the previous one, the spin of the air flow at the outlet can be partially used. The air supply to the chamber of the stator housing in the case of forced ventilation is shown in FIG. 3, in the case of self-ventilation in FIG. 4 and 5. To ensure the stability of the operation of the circuit, compensators 6 of the rotor head are used, which are centrifugal fans fixed to the rotor of the machine,

To implement the axial-radial ventilation scheme, FIG. 4, in the case of a self-venting machine, the main pressure element is a high-pressure centrifugal fan 7 with forward-curved blades and a blade guide apparatus 8E of the circuit in FIG. 5, the main pressure element is a centrifugal fan 9 mounted on the flywheel 10. The fan 9 creates a discharge, allowing the counter axial-radial ventilation scheme to be carried out.

A counter-axial-radial ventilation pattern provides better cooling of the rotor winds compared to the radial pattern. At the same time, cold air is supplied directly to the hottest surfaces and is more evenly distributed along the radial channels of the stator. The cooling surfaces increase due to the effective use of the back surface of the stator and a more uniform distribution of flow rates over the surface of the core packages inside the radial channels of the stator. The turbulence of the air flow in the gap increases and air is better filled with the interpolar windows.

When using rotor head compensators, the power of the fan is spent only on the increase in pressure, relative to the pressure behind the rotor and, therefore, to overcome the centrifugal forces of the rotor, neither increase in the head nor increase the power of the fan is required. Moreover, part of the energy of the swirling air is converted into static pressure during the unwinding of the flow behind the pressure compensators.

The proposed device for ventilation has been tested and is recommended for deployment.

Subject invention

Claims (5)

1. A device for ventilation of synchronous electric motors, in which cold air is injected into the chamber between the machine body and the stator back and passes through the radial channels and the machine gap into the interpolar rotor channels, characterized in that, to improve the cooling of the machine, the rotor is fixed on a centrifugal fan (vent compensator) designed to compensate for the rotor's resistance to the movement of air from the stator, thereby providing the required aerodynamic characteristic of the valve translational network. 2. A device according to claim 1, characterized in that two ventilator compensators located at both ends of the rotor are applied, which create a radial-axial in opposite directions air movement (counter radial ventilation system). 3. The device according to claim 1, characterized by the use of one ventilation compensator located at one end of the rotor and creating air movement radial-axial in one direction (opposite axial-radial ventilation system). 4. Device on PP. 1 and 3, designed for actuators with a flywheel, characterized in that the vent compensator is located on the inner face side of the flywheel and is also used to force air into the chamber between the housing and the stator back. 5. The use of the device on PP. 1--4 in systems of self-ventilation or forced ventilation of synchronous motors. № 141928 / V 3 ; / /. BUT. ziT ZJirrrb fuel Jl