SU1709468A2 - Electric machine - Google Patents

Abstract

The invention relates to electrical engineering. The purpose of the invention is to provide the necessary ratio of air flow through the rotor and stator channels and to reduce power consumption for cooling. The electric machine comprises a housing having an air inlet 5 for the air and a manifold 4. Due to the fact that throttling windows 6 are provided on the side opposite to the air inlet in order to expel an excess amount of cooling air, this goal is achieved. 1 il.

Description

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The invention relates to electrical engineering, mainly to electrical machines with cooling air inlet and outlet networks, for example, electric traction machines for railway locomotives.

A known electric machine consisting of a rotor and a stator mounted in a housing. On one Ithorian machine there are windows for supplying and discharging cooling air. A partition is installed inside the machine, separating the rotor channels from the stator channels, ensuring their sequential purging with the same flow of cooling air, which makes it possible to use the cooling air more efficiently and reduce its flow through the machine.

However, in a known machine, the same amount of cooling air passes through the channels of the rotor and the stator, which is not always advisable, since the necessary costs of cooling air through the channels of the rotor and stator are not the same. This does not allow a significant reduction in cooling power costs due to excessive pressure losses in one of the ventilation chains.

The aim of the invention is to reduce the power consumption for cooling and to provide the necessary ratio of air flow through the rotor and stator channels.

The drawing shows an electric machine with air cooling, longitudinal section.

The electric machine is made of a stator (magnetic system with axial interpolar channels) 1 and a rotor (cor) 2 with Axial channels 3. In the case from the side of the collector 4 there is an entrance window 5, and from the side opposite to the air inlet there are throttling windows 6. The partition function is performed by the protrusion 7 on the bearing shield 8 and the protrusion 9 on the manifold 5. In the bearing shield 8, exhaust ports 10 are provided, communicating with the subcollector cavity 11,

The cooling air flow enters through the inlet window, washes the collector 4 and flows through the interpolar channels of the magnetic system 1. The lobes of the winding 12 and the outer surface of the groove part of the core 2 are cooled by the same air flow. Then a part of the air is ejected through the throttling window-6. and the required amount of cooling air, determined with regard to its heating in the magnetic system, enters the axial channels 3 cor 2. From the axial channels the cooling air flow is supplied to the under-collector cavity 11 and discharged into the atmosphere through exhaust windows 10. The total air flow through the machine is determined by the required air flow for

cooling of the magnetic system. The flow through the axial channels of the core is determined from the condition that the specified core temperature is exceeded. The amount of air making up the difference between

0. Necessary expenses through the magnetic system and the axial channels of the core, Strav Livaets through throttling windows.

The hydraulic resistance of the throttling windows is determined by the formula

five.-- . :.; Y -; .,.::; -; / ,. . ;;. . : d to

2dr

(one)

;. to

1c {mcc Ccc

where qMOK and QflK are the necessary flow rates of cooling-: laying air through the channels of the magnetic system and core, respectively;

2 к - hydraulic resistance

cor .- /. . V: -, - - --.-

The power cost of cooling is

Nnqcrt 2.luTsmpk. ZMDKQM

ipc

(2) + C | Mnki

where ZBX and ZMHK are the hydraulic resistance of the input and interpolar channels.

When parallel purge with hydraulic resistance throttling windows Zflp.nap. power consumption for cooling is Mpar ZBx (qMnK + (k) + (+

Zflp.nap.) Chmpk + ZsicQflK, (3).

where I to - the necessary flow through the branch box.

The reduction in cooling costs is determined by the power difference Mpar Nnocn and is 15-30%.

Claims (1)

Reducing the cost of power for cooling in a car with sequential purging of ventilation branches and throttling windows is achieved by reducing the air flow through the inlet, while decreasing. The air flow rate through the second BeHf cooling branch to the required one, which leads to a decrease in pressure loss in it and a reduction in the power consumption for cooling the machine as a whole., Invention Formula Electric machine, auth.s. 1Мг 1508313, about tl and ch and y and so that, with the purpose of providing the necessary ratio of air flow through the rotor and stator channels and reducing the power consumption for cooling, in the case from the side, pro5It094686, ti opposite) to the air inlet, the exact number of thawing windows for the discharge of excess gas is made; ka