Change distribution moves in, transformer is indispensable, the dispute of basic common sense that be familiar with and masters transformer often is necessary, the basic knowledge reserve of transformer is person of each electric power’s necessary skill!

 

1, what calls transformer?

 

In alternating current road, the device that lift voltage or drops calls transformer, transformer can transform the voltage of either numerical value into the voltage that our place with same frequency needs to be worth, in order to satisfy the transportation of electric energy, allocate and use a requirement.

 

For example the report that power plant hair comes out, voltage grade is inferior, must lift voltage ability carries the more remote region that use phone, the area that use phone must turn applicable voltage into grade through step-down again, supply power plant reachs equipment of day of commonly used phone to use.
 

 

2, how is transformer to alternate of voltage?

 

Transformer is made according to electromagnetism induction. It uses silicon steel by piece (or silicon steel piece) the core that folds and two groups of coil that are circled on core are formed, each other are isolated from each other between core and coil, without the connection of any report.

 

Call transformer and coil of connective of power source a side primary coil (or call former edge) , call transformer and coil of connective of the equipment that use phone secondary coil (or deputy edge) . When receiving the primary coil of transformer alternating current source to go up, metabolic lines of force can arise in core.

 

Because secondary coil is circled on same core, secondary coil of cut of lines of force, inductive electromotive force arises necessarily on secondary coil, make coil two end occurrence voltage. Because lines of force is to hand in,change, so the voltage of secondary coil also is to hand in change. And frequency and power source frequency are identical.

 

Director reasoning is solid, primary coil and secondary coil voltage compare transformer and the specific value of v/LIT all over the ground number of primary coil and secondary coil is concerned, can express with next type: Primary coil voltage / v/LIT all over the ground number of primary coil of = of secondary coil voltage / secondary coil circles number explains v/LIT all over the ground number is more, voltage is taller. Because this can see, secondary coil is less than primary coil, it is step-down transformer. It is a step-up transformer instead.

 

3, what kind does transformer design have?

 

By photograph number cent has single-phase with three-phase transformer

 

By utility cent has electric power transformer, transformer of special power source, pressure regulating transformer, measure transformer () of voltage transformer, electric current transformer, transformer of small-sized power source (lead equipment) with Yu Xiaogong, safe transformer.

 

By the structure cent has core type and shell type two kinds. Coil has double winding and much winding, from Ou transformer.

 

By cooling means cent has type of refrigeration of oily dip type and air.

 

4, by what is transformer part formed partly?

 

Transformer component basically is comprise by core, coil, in addition still gasoline tank, oily pillow, insulated sleeve and cent receive first class.

 

5, what use does transformer oil have?

 

The action of transformer oil is:

(Action of 1) , insulation

(2) , medicinal powder hot action

(3) , eliminate electric arc effect

 

6, what is from Ou transformer?

 

Have a group of coil only from Ou transformer, secondary coil comes out from primary coil take a percentage of a deal, its electric energy is delivered, besides electromagnetism induction is delivered, what still have report is deferent, silicon steel of this kind of transformer piece want than general transformer with copper cash amount little, often use as adjust voltage.

 

7, how pressure regulating is voltage regulator?

 

The construction of voltage regulator and from Ou transformer identical, it is core consummate annular coil is circled on annular core only.

 

Secondary coil take a percentage of a deal touchs a head with an OK and slip brush, make surface of coil of the edge that touch a head annular and slip, achieve flowing adjustment voltage action.

 

8, is transformer primary is the voltaic concern of coil and secondary coil what kind of?

 

When transformer contains load to move, the change of secondary coil electric current, can cause the change with primary coil corresponding electric current. According to magnetism situation balance principle derivation goes out, primary civilian the electric current of secondary coil and coil circle number becomes inverse ratio, v/LIT all over the ground number is much at the same time electric current is small, v/LIT all over the ground number is little at the same time electric current is big.

 

Can express with next type: Primary coil electric current / v/LIT all over the ground number of secondary coil of = of secondary coil electric current / primary coil v/LIT all over the ground number.

 

9, the voltage change ratio that what is transformer?

 

The voltage change of voltage regulator leads one of main function index that are transformer. When transformer to laden power supply when, the voltage that carries in the load of transformer can drop necessarily, descendent voltage value and rated voltage are worth photograph comparing, take percentage namely voltage change ratio,

 

Usable formula states; voltage change leads =[(sub and rated voltage – load carries voltage) / sub and rated voltage] ×100% . Normally electric power transformer, receive on when rated load, voltage change ratio is 4 ～ 6% .

 

10, how to make sure transformer has a rated voltage output?

 

The regular job of transformer of influence of too tall or too low metropolis mixes voltage service life, so must pressure regulating.

 

Pressure regulating method is derivative in primary coil a few take a percentage of a deal, receive begin is received to go up in cent, cent receives begin to touch a head to change the v/LIT all over the ground number of coil through roll. Want to turn cent accepts the position of switch only, can get the rated voltage of need is worth. Those who want an attention is, pressure regulating should be in normally the laden and junior travel that cuts off transformer place to receive.

 

11, is the small-sized transformer that uses normally what kind of? Is application in what circumstance?

 

Small-sized transformer shows the capacity installs the following single-phase transformer in 1 kilovolt, use as likely the power source transformer that electric device control character uses, the power source transformer of electronic equipment reachs the power source transformer that safe illume uses.

 

12, what loss does transformer have in move? How to reduce a loss?

 

Transformer runs medium loss to include two shares:

 

(1) , cause by core, after coil electrify, because lines of force is to hand in,change, cause the backset in core and magnetic hysteresis loss, caustic of iron of a general designation of this kind of loss.

 

(The 2) , resistor that is coil oneself causes, when transformer primary coil and secondary coil have electric current to tell past the appointed time, be about to produce electric energy loss, this kind of loss calls copper caustic.

 

Of iron caustic and cupreous caustic mixing is transformer loss, these losses and transformer capacity, voltage and utilization rate of equipment and installations are concerned. Accordingly, when choosing transformer, should make equipment capacity is mixed as far as possible make dosage actually consistent, in order to raise utilization rate of equipment and installations, the attention does not make transformer light convey by vehicles goes.

 

13, the nameplate that what is transformer? Data of what main technique is there on nameplate?

 

The nameplate of transformer indicates standards of the function of this transformer, technology and use circumstance, choose with what will satisfy an user, the main technique data that chooses an attention normally has:

 

(The kilovolt of 1) , nominal capacity brings number. Namely the output capacity of the transformer below rated condition. Be like line of =U of single-phase transformer nominal capacity line of =U of capacity of transformer of three-phase of ×I line; ×I line.

 

(Bend over of 2) , rated voltage is counted. Indicate respectively the carries voltage and secondary coil upright voltage of primary coil (when receiving load) value. The upright tension that notes three-phase transformer shows line of line voltage U is worth.

 

(Amperage of 3) , rated electric current. Point to mix in nominal capacity allow temperature rise condition to fall, primary coil and secondary coil allow the cost of line of I of line electric current that passes for a long time.

 

(4) , voltage is compared. Show primary coil is rated voltage and secondary coil are rated of voltage than.

 

(Means of 5) , wiring. Only discretion presses single-phase transformer each group of coil, furnish only single-phase use, three-phase transformer has Y/ △ type. Outside dividing above technology data, the impedance per cent of number of the rated frequency that still has transformer, photograph, temperature rise, transformer.

 

14, how to choose transformer? How to determine the reasonable size of transformer?

 

Want to investigate the power source voltage of the place that use phone above all, the uses electric bear and place place actually condition of the user, consult next the choice of technical data one by one of transformer nameplate designation, answer to consider integratedly from transformer capacity, voltage, electric current and ambient conditions commonly, among them the capacity that the capacity chooses to should use electric device according to the user, property and the bear quantity that use time will come decide place needs, will choose transformer capacity with this.

 

When moving normally, the 75 ～ that should make transformer susceptive is transformer nominal capacity with electric bear 90% the left and right sides. Transformer goes out to bear actually like actual measurement in moving bear 50 be less than % when, should change small size transformer, if be more than transformer nominal capacity,should change instantly big transformer.

 

In the meantime, in the choice transformer decides according to circuit power source the primary coil voltage of transformer is worth, choose the voltage value of secondary coil according to using electric device, had better choose for low-pressure three-phase 4 lines make power supply. Can offer motivation to use phone with report and illume at the same time so.

 

The demand that should notice to voltaic choice bear can satisfy electromotor when electromotor starts (when because electromotor starts electric current,wanting to move than sinking big 4 ～ 7 times) .

 

15, why cannot transformer cross bear to move?

 

Crossing bear to move is the voltaic value that the regulation on nameplate exceeded when showing transformer moves.

 

Cross bear cent to pass negative charge to cross bear and accident normally two kinds, former it is to show in normal power supply the circumstance falls, the user increases with n and cause, it often makes transformer temperature elevatory, make transformer insulation ageing, lower service life, do not allow transformer to cross bear to move so.

 

Inside short time of the transformer below special situation cross bear to move, also cannot exceed the 30%(winter) of rated bear, 15% must not exceed in the summer.

 

To latter, the accident crosses bear and had allowed time requirement to see next tables.

 

 

16, which a few kinds of tests should transformer do in move?

 

To make sure transformer can move normally, often should undertake following a few tests:

 

(1) , temperature checks. Transformer moving condition is normal, the discretion of temperature is very important. Oil of regulations provision upper levels is lukewarm must not exceed 85C(namely temperature rise 55C) . General transformer determines of special temperature device.

 

(2) , bear determines. To raise the utilization rate of transformer, reduce the loss of electric energy, move in transformer in, must determine the power supply ability that transformer can assume truly. Determine the job uses electric peak period to undertake in each season normally, determine directly with pincerlike ammeter. Voltaic value should be transformer the 70 ～ of rated electric current 80% , the specification when exceeding passes negative charge, answer to be adjusted instantly.

 

(3) , voltage determines. Regulations requirement voltage changes limits should be in less than of rated voltage ±5% . If exceed this one range, should use minute of connect to undertake adjustment, make voltage reachs formulary range. Measure secondary coil to carry voltage and the end that did not carry an user respectively with volmeter commonly voltage.

 

(4) , insulation resistance determines. Run state normally to make transformer is in from beginning to end, must have insulation resistance determine, be isolated from in case ageing and reason of hair make trouble. When determining, should try to make transformer stops to move, use shake the watch determines value of transformer insulation resistance, requirement place measures resistance not under 70% what what measure a value before, choose shake when the watch, low-pressure coil can use social estate of voltage of 500 bend over.