DE1918606C - Step switch for regulating transformers - Google Patents

Description

c ^ ,. «"! ίίΐϊΐ! " ⁸ ι of the ^{step switch} after each with a main contact 13 or 15 of the moving

Invention is particularly voueilhaft when the control ii _chen contact members 11 and 12, respectively. the

of the diverter switch two auxiliary contacts 14 and 16 of the movable contact

Jm the steady state of the members 11 and 12 are rzw via lines 23. 24

c »» - 'I ^e S ^en · This makes the 5 with the primary winding each of a control transformer

• - ~ w, <. « T " ⁰¹¹⁸ JfI ^ State of the tap changer 25 or 26. Since the primary windings of this

, η halved each circuit, and only in the whole control transformers 25 and 26 across the lines

The semiconductor valves 21 and 22 are also connected to the main contacts 13 and 15 for a short time during the switchover

of a circuit fully loaded, so that the movable contact members U and 12 are connected accordingly

smaller controllable semiconductor valves are used, is connected to the control transformers 25 and 26

be able. _{in the stationary} state of the step selector W in each case

add another appropriate embodiment of a step voltage of the transformer Tr an.

Scha ers then exists that parallel to each anti- The control circuit is controlled by the control trans

parallel connection of the controllable semiconductor valves per formators 25, 26 via the resistors 27, 28, the

A voltage measuring device is located, which iiher te HrV, rV * _n ai »irh ™ ht * T ta in ,. * aa; * T ^ rAi _n A * ti

HrucKenaicicnncnier each one AND gate of the control fed. The tax circle consists essentially

^St η "* Ta ^S T ^U u ^ ^{lichen from the} trigger stage.", The AND gates 33

Due to the design of the step switch according to and 34 and the pulse generator 35, 36.
brtinuung is achieved that the vo.i the stages parallel to the antiparallel circuits controllable voltage aogleitende power supply of the control ao semiconductor valves 17, 18 or 19, 20 are voltage circuit is never interrupted, even if detection devices 41, 42. They control over the Bridging parallel circuits of the diverter switch gr ^ ichrichter 43 and 44 the AND gates 33 and 34 are energized at the same time, so that at any time one and indicate whether the circuit St ₁ or St ₂ is blocking trouble-free switching of the diverter switch.

can be taken xann. This is the prerequisite 25. The control roller 50 has a sliding contact 51.

for a switching method in which the previously different alternating on the contact tracks 52, 53, 54

used mechanical permanent main contacts and 55 loops. This sliding contact 51 is with the

It is efficient not only to drive these contacts, but also to drive the movable contact members 11 and 12

but also the necessary drive means of the tap selector W are coupled. The control drum 50

can be saved. ₃ ″ _{firstly gives} control signals to AND gates 33

r " α ^z . ^eicnnun ß ^{is an} embodiment of the or 34 and secondly control signals to the E-'ngäng-e E _x

It shows or E _{2 of} the flip-flop 32, with its output

Hg-I a circuit diagram of the multiple switch with terminals A ₁ and A ₂ with input terminals E ₂

Control circuit and a schematic representation of AND gates 33 and 34, respectively, are connected. the

of the Sturenwahlers, ₃₅ resistors 56, 57, 58, 59 are used for preloading

l x 1 g. 2 to 6 the different switching positions of the control roller 50. The diodes 60, 61, 62, 63 in front

Step converter during the switching process of the step AND gate 33 and the diodes 64, 65, 66, 67

switch and _{before the} AND gate 34 are used for decoupling

f 1ig. 7 the mechanical control drum with the various control commands. The initial

Steps of the step selector corresponding to 40 terminals A ₁ of AND gates 33, 34 feed depending on

Switching steps. Release via pulse generators 35, 36 each

The step switch consists of the diverter switch L thyristors 17, 18 or 19, 20 of the circuit St ₁

and the tap selector W, which is connected to the taps A and St ₂ .

B, C, D üer step winding of the transformer Tr The arrangement should be based on a switchover

connected. Oi *. Taps A, B, C. D are explained in more detail 45 of the tap changer according to the invention

dm with fixed contacts A _1, B _1, C _1, D ₁ a are:

Switching level of the step selector and at the same time as the starting point for the switchover is the position of fixed contacts A ₂ , B ₂ , C ₂ , D _{2 of} a second ^J .es step selector W according to FIG. 2, which are also connected to the switching level of the tap selector W. The position of the step selector W according to FIG. 1 corresponds to fixed contacts A ₁ , B ₁ , C ₁ , D ₁ of one 50. The moving main contacts 13 and 15 are level via a line 10 with the fixed contacts B ₁ and B ₁ contact, standing contacts. A ₂ , B ₁ , C ₂ , D _{% of} the other level The movable auxiliary contact 14 is permanently connected to the. The stage selector JK is still connected to contact C ₁ . The control with two movable contact elements 11, 12, transformer 25 therefore receives the step voltage via the lines 21, see each of two mechanically coupled 55 23, the main and auxiliary contacts 13, 14 and 15, 16 between the taps B and C of the control winding of the transformer Tr and in the same two switching levels that is fixed. DeT movable auxiliary contact 16 of the stepped contacts A ₁ , B ₁ , C ₁ , D ₁ or A ₂ , B ₂ , C ₂ , D ₂ selector is located with the fixed contact A ₂ . The moving main and auxiliary contacts 13, connection. The variable transformer 26 receives a step voltage at such a distance of half over the lines 22, 24 rigidly coupled to each other that they are simultaneously on two fixed contacts between the taps A and B of the step neighboring , eg B ₁ , C ₁ winding of the transformer Tr is pending. Both control or A ₂ , B ₂ , each can rest on a switching level. transformers 25, 26 feed in parallel in the

The diverter switch L consists of two parallel control circuits.

lying circuits 5Z ₁ and St ₂ , which in turn consist of 65 The sliding contact 51 of the control roller 50 is there

Anti-parallel connections of controllable semiconductor valves this time I ₀ contact connection between

(Thyristors) 17, 18 and 19, 20 order. The two of the Konfiktbahnen 52 and 53. The resistors 58,

Circuits St _{1 and} St ₁ are supplied via lines 21, 22 59, as a result of which voltage and likewise the

5 6

Inputs E ₁ and E _{2 of} both AND gates 33 and 34. lane 53 (position J ₄ ), the switchover is as follows: As soon as both inputs of the AND gate maintain voltage in the first following zero crossing of the load, their outputs A ₁ also carry voltage, current after the running of the sliding contact 51 the pulse generators 35 and 36 are released on the contact track 54 the switching of the load and ignite both circuits St ₁ and St _{2 of} the load transfer current from the circuit St ₁ to the circuit switch / ,, the thus in parallel the load current St _{2 of} the diverter switch and thus from the tap from tap B of the step winding of the transformer B to tap C of the step winding of the transformer Tr via the lead Tan lead the load. Transformer Tr takes place. The flip-flop 32 is now

Now comes a command to switch the stage voltage via its output A ₃ voltage to input E ₁ 2;

switch, for example, from the tap B to the io of the AND gate 33. Likewise, the input E _{receives 1}

Tap C, the moving contact of the AND gate 33 begins via the transformer 41 and

link 12 with its main and auxiliary contacts 15 the bridge rectifier 43 voltage, since now the ___

and 16 is applied in the direction of the fixed contact C ₁ or step voltage on the circuit St ₁ . /

Move Bi (Fig. 3). As the sliding contact 51 continues to rotate

In this case, the supply of the control circuit 15 of the control drum 50 runs at the time t _{t of} the loop via the control transformer 25. With contact 51 on the contact track 53, whereby the movement of the step selector ff begins and AND gate 33 at its inputs E ₁ and E _{2 of} the sliding contact 51 of the control roller 50 against additional voltage receives. As the sliding contact 51 rotate clockwise. In the process, the sliding contact 51 leaves the contact track 53 (position J ₁ ) until it returns to its starting position I _0. ^ao path 53 is constantly touched, the circuit also remains. As a result, the pulse generator 35 is no longer released via the AND-St ₂ regardless of the further switching sequence current gate 33, that is, blocked. In the leader.

Position t _{2 of} the sliding contact 51 of the control roller 50 While the sliding contact 51 moves further from the movable main contact 15 and also the position t _A to ^, the contact member 11 opens the movable auxiliary contact 16 of the step selector further 35 with the movable main and auxiliary contacts 13 iin open- The sliding contact 51 is now but both and 14 its contact position and moves in -nit the contact track 52 as well as with the contact direction of the fixed contacts C, and D _{1 of} the jahn 55 contact, whereby the resistor 56 and tap selector (Fig. 5). The supply of the control input E _{2 of} the flip-flop 32 voltage received circuit is now done via the control transand thereby the flip-flop in that switch position 30 formator 26. At the time t _s the control roller 50 runs, in which its output terminal A _{1 of} the grinding point 51 is brought up again the contact track 52 carries voltage and thus also the input E _{t of} the. As a result, the AND gate 34 enables the pulse JND gate 34th generator 36, so that this firing pulses are sent to the In F i g. 4 is the step selector W in a switching circuit St ₁ supplies. As soon as the contact member 11 comes division, in which the movable 35 groove the movable main and auxiliary contacts 13,14 -lauptkontakt 15 runs on the fixed contact C ₁ on the fixed contacts C ₁ and D ₁ (Fig. 6), ind the movable auxiliary contact 16 on the fixed- the circuit St _{1 is} energized, and the standing contact B _{2 is} seated. The circuit Si ₁ circuits St ₁ and St _{t of} the diverter switch share les diverter switch continues to carry load current, while the load current that flows from tap C to the end of the circuit St _t the step voltage between 40 step windings via the Y line . The len taps B, C of the tap winding of the transformation sliding contact 51 remains in its original ormators Tr is applied and the transformer 42 DA initial position I ₀ and is ready for another switching lurch a DC through the rectifier bridge 44th If this switchover occurs in the direction of the voltage signal at the input E _{1 of} the AND tap D of the step winding, then Jatters 34 repeats itself. The curve just described is thus present at both inputs E _{x 45.} If the switchover in E ₂ of AND gate 34 is to take place without the control but back in the direction of tap B , voltage via the control roller 50, voltage on, and so the sliding contact rotates in the opposite sliding contact 51 of the control roller 50 in the sense of rotation and the movable contact members 11 leave the contact track 52 with a further rotation and 12 move so that first the contact member 11 is in position Z ₃ ). From this point in time to 50 and then the contact member 12 switches in the direction of revolving the sliding contact 51 to the contact tap B of the step winding

1 sheet of drawings

Claims (4)

1 2 There are arrangements for load switching of the claims: Step winding of regulating transformers with controllable semiconductor valves, such as thyristors or triac; 1. Step switch for regulating transformers with known, in which, however, the readiness in the diverter switch arranged, even in the stationary S position of the supply voltage for the control of the nary state without permanent main contact, the load semiconductor valves is entered. Since the antiparallel circuits carrying the control switch are usually at a potential with respect to earth of the semiconductor valves whose ignition pulses are above, a control voltage supply via a control circuit from the step voltage to an isolating transformer is required. Which can be derived here, and with a tap selector whose io resulting displacement currents via the capacitive contacts with the respective activities of the transformer, which can have an unfavorable influence on the control taps of the transformer tap winding, as well as the stresses, are identified by a corresponding one Space with larger net. that the step selector (W) for the potential differences between switch and earth taps (A. B, C) of the mare's performance two 15 let it jcuui.ii ία «« ... "...» ι ..: .—, j: - O _n -.... ^ switching levels besi'.a each with a fixed supply of the control directly or indirectly from the contact (A ₁ , B ₁ , C ₁ or A ₂ , B ₂ , C ₂ ), derived from the respective step voltage. For this purpose, the two of a tap (A and B known (Belgian patent 612 572), the steps or C) are galvanically connected to each other, voltage via the free selector contact in front of and with each movable contact element (11 or ao switchover on the According to 12), which consists of a mechanical switchover, the non-current-coupled main contact (13 or 15) and auxiliary selector contact are opened so that the contact (14 or 16) consists, each Contact supply of the control ^ romkreises only while the element (11, 12) is guaranteed in its switching level to the permanent switchover. standing contacts (A ₁ , B ₁ , C ₁ or Λ ₂ , B ₂ , C ₂ ) 25 Furthermore, according to the German interpretation of two adjacent taps (A, B or B, C) 1 249 398, the control units of a the tap winding became known in the same switching level of the tap changer, in which the switches on and at the same time i-.it the tapping of the regulating winding in three levels, each of which is mechanically placed between the two, and always one selector contact per coupled main and Auxiliary contacts (13, 14, 30 switching level are available, with at least two or 15, 16) stepped main selector contacts lying on a switching level always closed and all voltage to a control transformer (25 or three selector contacts for the full load current off) Supply of the control circuit is applied. must be laid. This means that when using 2. Tap changer according to claim 1, characterized in that the controllable rectifier then has three pairs of antiparallel, that the control circuit required a 35 switched thyristor, and moreover contains mechanical control roller (30), which must have three disconnectors to drive the thyristor current the movable contact members (11, 12) are connected upstream. After that, however, the of the step selector (WO is coupled. Circuit considerably more expensive. 3. Step switch according to claim 1 or 2, the invention has the object, characterized in that the controllable 40 step switch of the type described above has a semiconductor valve (17, 18 and 19, 20) of the load continuous supply of the control devices for the Changeover switch to form two circuits (St ₁ and Sf ₂ ), thyristors in the simplest manner with the slightest indentation in the steady state of the tap changer set of thyristors and auxiliary switches to allow parallel. This is achieved by the fact that according to the invention 4. Step switch according to one of claims 1 45 step selector for the taps of the step winding up to 3, characterized in that it has parallel to two switching levels, each with a fixed antiparallel connection of the controllable half-contact, each of which has a tapping conductor valve (17, 18 and 19, 20) a voltage are galvanically connected to each other, and with each detection device (41 or 42) is located, which is via a movable contact member, which is made up of each bridge rectifier (43 or 44) an AND 50 with each other Control mechanically coupled main gates (33 or 34) of the control circuit. contact and auxiliary contact, each Contact member in its switching plane on the fixed contacts of two adjacent taps ——— * of the step winding in the same switching level 55 switches and at the same time with the step selection the mechanically coupled between the two The invention relates to a step switch main and auxiliary contacts of a switching level for regulating transformers with step voltage in the diverter switch to apply to a control transformer, even in the steady state without supplying the control circuit.
Permanently main conUikt the load current leading anti-60 The control circuit consists in advantageous parallel connections of controllable semiconductor valves, whose way of known electrical assemblies and Züiulimpulse over a control circuit from an electrical or mechanical command generator. Step voltage can be derived, and with a step The command transmitter is, for example, a magnetic selector, the fixed contacts of which are connected to each band or a photoelectrically operating perforated disk, some taps on the step winding of the transmission. Through these stages switch circuit a mechanical control roller, which is with a cm. '. Xhtbogcnfreies switching of the load current driving the movable contact members of the tap is coupled ^{NRR "iil11} selector.