CN201667591U

CN201667591U - Asynchronous motor with startup voltage-reducing winding

Info

Publication number: CN201667591U
Application number: CN2009203511022U
Authority: CN
Inventors: 丛伟滋
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-12-16
Filing date: 2009-12-16
Publication date: 2010-12-08
Anticipated expiration: 2019-12-16

Abstract

The utility model provides an asynchronous motor with a startup voltage-reducing winding, which is added with an auxiliary winding with the same phase on a motor principal winding. The utility model can overcome the influence on the electric network caused by great current during motor startup, the startup characteristic index of the motor can be improved, when being applied for the single phase, the auxiliary winding is connected onto a principal winding circuit in series during startup; during normal running, the auxiliary winding is converted on to the secondary winding in series. Because of reinforcing the whole benefit of the motor, the startup factor can not be compromised, the electromagnetic parameters can be designed based on the normal running standards, two machine base numbers can be reduced compared to the common single phase motor with the same power.

Description

Asynchronous motor from tape starting step-down winding

Technical field:

The utility model relates to a kind of winding construction that changes and reduces starting current, from the asynchronous motor of tape starting step-down winding.

Background technology:

No matter three-phase or monopole asynchronous motor, all be by the required Winding Design of carrying out of normal operation, inevitable reality, be the several times that electric current when starting initial (or stall) surpasses normal operating current, running current reduces along with the raising of rotating speed, just reduces to normal numerical value after only reaching rated rotational frequency.

Since monophase current have only " pulsation " and impossible as three-phase current the complete rotating magnetic field of direct formation, so monopole asynchronous motor just needs additional assembly to produce and keep the power of rotation, the most universal current way is " splitting phase " effect that relies on electric capacity to produce, use the auxiliary winding of series capacitance to combine, constitute the rotating magnetic field of motor stator with the operation main winding.

In fact in the monophase machine for beginning postrotational cage rotor, single-phase " alternation " electric current that acts on main winding is as good as with the effect of three phase rotating field; The auxiliary winding of series capacitance then forms and keeps stable rotation power better, so the monophase machine of " capacitor start " and " capacitor operating " two kinds of different structures is just arranged and deposit, self-evident better structure is subsidiary simultaneously the startup and two electric capacity single-phase motors (Fig. 1) of running electric capacity.

The factor of decision motor-driven ability is the intensity of rotating magnetic field, and to the fixing electromagnetic structure of other factors, magnetic field intensity depends on the electric current of coil and the product of the number of turns (number of ampere turns), and the effect of voltage is to overcome the enough electric currents of reactance generation.In the practical application of motor device, for the reactance factor that overcomes the electric motor starting process reduces the big electric current that causes significantly, the means of taking start-up course to reduce the motor supply power voltage usually reduce the starting current of motor windings.

Though the principal element of decision motor effect and current drain is electromagnetic structure, because the overall targets such as influence to different factors in the different needs of continuous driving force and startup ability, the Electromagnetic Design in the practicality are difficult to plan as a whole standard, so can only formulate the standard of directiveness at electromagnetic structure, and formulate corresponding national standards to the power grade related with the related overall dimensions (seat No.) of product application apparatus with power consumption.Inquire into from the angle of protection of consumers' rights and interests, for the purposes scope of appointment, the electromagnetic structure of same standard, the power grade of various criterion and supporting seat No. just have implicit mandatory country one to one or industry standard.Because monophase machine needs the extra auxiliary winding that produces auxiliary magnetic field that increases, usually to the requirement of monophase machine support than planning standard with the high grade of three phase electric machine support of power grade.

Summary of the invention:

For overcoming the influence that the big electric current of electric motor starting process causes electrical network, improve the starting characteristic index of motor, it is a kind of the parts that reduce the electric motor starting function of current that the utility model provides, and is integrated into the asynchronous motor from tape starting step-down winding of motor internal.Concrete technical measures are the main winding positions in the motor operate as normal, the auxiliary winding of an additional homophase coiling, and in the start-up course of motor, power supply is connected in series on the main winding circuit by the changeover contact that is independent of electromagnetic structure; And when normal operation, be converted to main winding independent operating state (Fig. 2).

Because start-up time, the very short overheated factor that can ignore long-time running was selected the line footpath coiling auxiliary winding little than main winding, increased the reactance of starting state to make full use of the confined space, fully reduced the electric motor starting electric current as far as possible.

The startup factor is taken all factors into consideration in contrast, different capacity grade building machine seat number is formulated the common asynchronous moter of national standard, the utility model is owing to increased the number of turns behind the auxiliary winding of start-up course series connection, the overall number of ampere turns of electric current after main winding reduces relatively increases to some extent, because of having improved the overall efficiency that detent torque strengthens motor, can or seldom take into account the startup factor, only pressing on the basis of the well-designed electromagnetic parameter of standard that runs well, reduce the dimensional standard (seat No.) of a grade.

For the auxiliary winding of capacitor operating or startup, the two electric capacity single-phase motors of running, the utility model only makes full use of the auxiliary winding that when starting series connection is applied to main winding, changes to be concatenated on the auxiliary winding circuit when normal operation.So auxiliary winding is at the electric current of start-up course, because of main winding reduces the pressure drop " increase " that starting current reduces; Because of auxiliary winding wire diameter is bigger than auxiliary winding, instead the winding of combination total number of ampere turns when reducing electric current increases to some extent during normal operation.Facts have proved because of the overall lifting of service performance like this, on the integrally-built basis of appropriate design, can reduce the dimensional standard of a grade again, make the seat No. of this structure monophase machine, even than the common three phase electric machine also little No. (or littler No. two than common monophase machine) with power.

Description of drawings:

Fig. 1 is common startup---the circuit theory diagrams of the two electric capacity single-phase motors of running.

Fig. 2 is the principle schematic of power supply through changeover contact changing-over main winding or auxiliary winding.

Fig. 3 starts step-down winding and two supporting monophase machine elementary diagrams of condenser network.

Fig. 4 is the three phase electric machine principle schematic of the auxiliary winding of band.

Fig. 5 is the wiring schematic diagram of two condenser network monophase machines of special centrifugal switch tape starting step-down winding.

Fig. 6 is the structural representation of special centrifugal switch KJ among Fig. 5.

The unified numbering of each map logo is as follows:

The LZ main winding; LF is an auxiliary winding; FZ is auxiliary winding; K is a centrifugal switch; QC is for starting electric capacity; YC is running electric capacity; J is a switching relay; DD is moving disconnecting point; DH is a normally opened contact; The three-phase terminal of power supply when A, B, C are normal the operation; AQ, BQ, CQ are the startup terminals of three phase mains; , O is the center tie point of three phase windings.

Embodiment: further introduce execution mode of the present utility model below in conjunction with accompanying drawing.

Embodiment one: start step-down winding and two supporting monophase machines of condenser network

Because of being in closure state in start-up course, centrifugal switch K is communicated with startup electric capacity QC in Fig. 3 circuit, power supply inserts motor circuit by the moving disconnecting point DD of switching relay J, auxiliary winding FZ and main winding LZ tandem working, after the approaching specified running speed of rotating speed, because of the adhesive of centrifugal switch K relay, power supply directly is communicated with main winding LZ through normally opened contact DH, auxiliary winding FZ and running electric capacity YC, auxiliary winding LF series operation.

Embodiment two: the three phase electric machine of the auxiliary winding of band

Fig. 4 simply described star connection three phase electric machine on original three-phase main winding, add the auxiliary winding of step-down of limiting starting current respectively.Three phase mains connects A, B during normal operation, the C terminal is equal to common three phase electric machine; Three phase mains connection AQ, BQ, CQ terminals during startup, the control circuit of startup---operation can be selected for use arbitrarily, and background technology does not describe in detail.

Embodiment three: two condenser network monophase machines of special centrifugal switch tape starting step-down winding

Use special centrifugal switch KJ to replace switching relay in Fig. 5 circuit.Common centrifugal switch described simply itself be exactly a moving disconnecting point, as long as on reed and insulation board correspondence position, handle DD1 and the DD2 of two groups of contacts in just can solution figure side by side; At the vacant position riveted joint in the corresponding reed HP of an insulation board JB both sides metal " bridge " JQ, corresponding D H contact (with reference to figure 6 structural representations) is inlayed in the position of corresponding reed contact CD.

Claims

1. asynchronous motor from tape starting step-down winding is characterized in that: the auxiliary winding of main winding serial connection homophase coiling cooperates the changeover contact of gating main winding or series circuit to be connected to circuit.

2. according to the described asynchronous motor from tape starting step-down winding of claim 1, it is characterized in that: auxiliary winding wire diameter is less than main winding.

3. according to the described asynchronous motor of claim 1, it is characterized in that from tape starting step-down winding: do not take into account the startup factor only by normal operation standard design electromagnetic parameter, can be by reduce a seat No. with power grade.

4. according to the described asynchronous motor of claim 1 from tape starting step-down winding, it is characterized in that: the auxiliary winding of capacitor operating or two electric capacity single-phase motors, conversion is serially connected with the main winding and auxiliary winding circuit when starting or turn round, can be by reduce two seat No. with power grade.

5. according to the described asynchronous motor of claim 1, it is characterized in that: the auxiliary winding of the subsidiary respectively step-down of three phase windings of the auxiliary winding three-phase motor of band from tape starting step-down winding.

6. according to the described asynchronous motor of claim 1 from tape starting step-down winding, it is characterized in that: special centrifugal switch is to handle two groups of contacts on common centrifugal switch reed, corresponding one by one with insulation board, correspondence position of insulation board riveted joint is inlayed the metal " bridge " of contact.