CN2105748U - Autoinductive coupling transformer for electric motor voltage reducing starter - Google Patents

Abstract

The utility model relates to an autoinductive coupling transformer for an electric motor voltage reducing starter; each winding of the three-phase windings thereof is provided with a tap; the tap can be 65%Un or 80%Un, and can be selected by a user. Compared with an original double taps, copper wires can be economized; iron cores can be decreased; the weight of a transformer can be reduced; the cost can be reduced by about 40%.

Description

Autoinductive coupling transformer for electric motor voltage reducing starter

The utility model relates to a kind of motor reduced-voltage starter autotransformer, belongs to the technical field of low-voltage electrical apparatus.

Motor often adopts autotransformer decompression starting, for example QJ ₃Series auto-transformer starter (referring to Fig. 1) is when operating grip CS pushes " startup " position, J to ₁, J ₂, J ₃, J ₄, J ₅Closure, three phase mains 380V voltage is by the A of autotransformer ZB ₁, B ₁, C ₁Through tap A ₃, B ₃, C ₃(D) provides low-voltage to motor, makes the motor decompression starting, when motor start-up electric current I=1,5In(In are the motor rated current) time operating grip push " running " position, J to ₁, J ₂, J ₃, J ₄, J ₅Disconnect, the self coupling transformation is thrown away, J ₆, J ₇, J ₈Closure, the operation of motor full voltage.

The QJ of present domestic employing ₃Series QJ10 series auto-transformer starter reaches the employed autotransformer of XJ01 type self-coupling decompression starting control cubicle and JJ1 series self-coupling decompression starting control cubicle and all adopts two-tap, its electrical principle, as shown in Figure 2, A ₃, B ₃, C ₃Be 65% ∪ n(or 60% ∪ n) tap, A ₂, B ₂, C ₂It is 80% ∪ n tap, select one of them tap by the user during use, and in fact exhausted most user is in selected tap no longer change later on, yet transformer with two-tap, the diameter of wire of three sections coils of its every group of winding all must be chosen by the maximum current that may occur, therefore no matter move selecting for use under any tap mode, always having the line of a section or two sections directly to seem in the every phase winding of transformer selects slightly, as calculated under the identical situation of current in wire density, make waste of material, increase cost.

The purpose of this utility model is that a kind of motor reduced-voltage starter autotransformer will be provided, it is by the design of two-tap, change the structural shape of fixing a kind of tap into, it can avoid above-mentioned shortcoming, through calculating under the identical situation of current in wire density, the structure of the single tapping ratio two-tap of 65% ∪ n can be saved the single tap of copper cash 13%, 80% ∪ n and also be saved copper cash 25% than the transformer of two-tap, because the winding cross section is little, core window and volume can correspondingly be reduced simultaneously.

The purpose of this utility model is achieved in that main former transformer commonly used is changed into by 2 taps and has only a tap, and it can be the tap of 80% ∪ n or 65% ∪ n, and the winding conducting wire cross section is determined on demand, reaches the purpose of saving copper cash.

Fig. 1, motor reduced-voltage starter schematic diagram

The schematic diagram of Fig. 2, two-tap

The schematic diagram of Fig. 3, single tap (80% ∪ n tap)

The schematic diagram of Fig. 4 list tap (65% ∪ n tap)

The schematic diagram of Fig. 5, autotransformer

Now in conjunction with the accompanying drawings the motor reduced-voltage starter is further narrated with the structure of autotransformer.

Fig. 2 is the schematic diagram of two-tap, A among the figure ₃, B ₃, C ₃Be 65% ∪ n(or 60% ∪ n) tap, and A ₂, B ₂, C ₂Be 80% ∪ n tap, transformer is always pressed maximum current during fabrication and is selected winding conducting wire.

Fig. 3, Fig. 4 are single tap schematic diagrames, manufactory had both produced 80% ∪ n single tap to the autotransformer of same power, also production has the single tap of 65% ∪ n, supply according to the user is selected, two sections coils of every like this phase winding can be selected diameter of wire by all electric currents of actual motion, have avoided the two-tap wasting phenomenon.

Single tap autotransformer of 80% ∪ n, two sections W of every phase winding ₁, W ₂Respectively by 3,14In, 0,784In chooses conductor cross-section.

Single tap autotransformer of 65% ∪ n, two sections W of its every phase winding ₁, W ₂Respectively by 2,07In and 1,115In choose conductor cross-section.

Fig. 5 is the schematic diagram of single tap autotransformer, and three phase windings have only a tap A among the figure ₂, B ₂, C ₂, it can be the tap of 65% ∪ n, also can be the tap of 80% ∪ n.Compared to the prior art, use the motor starter of single tap to have following advantage with autotransformer.

1, the identical situation of current in wire density, the transformer of the single tapping ratio two-tap of 65% ∪ n can be saved copper cash 13%, and the transformer of the single tapping ratio two-tap of 80% ∪ n can be saved copper cash 25%.

2, be accompanied by choose reasonable current density and multi-scheme and select preferred plan, (11～75KW) weight can alleviate 15～35% to the design's transformer, and volume can dwindle 19～35%, and material cost can descend 30～45% under same power.

Claims (3)

1, a kind of motor machine reduced-voltage starter autotransformer is characterized in that its three phase winding only respectively has a tap (A ₂, B ₂, C ₂).

2, transformer according to claim 1, the tap that the single tap winding that it is characterized in that transformer can be 80% ∪ n.

3, transformer according to claim 1 is characterized in that transformer list tap winding can be the tap of 65% ∪ n.

Images