DE2736934A1 - Rectifier distortion reduction system - uses transistor switches and transformer having low losses and giving low distortion on AC input - Google Patents

Abstract

The circuit reduces rectifier generated distortion on the AC side. It comprises a rectifier bridge(3) coupled to the supply through a choke (2). The rectifier output feeds a centre tapped transformer via transistor switches (11, 12) at each end of the winding. The transformer output is connected by thyristors and diodes(13-20) to one pole of the DC(5), the other pole being directly connected to the rectifier. The transistor switches and the transformer output switches are controlled to give unidirectional quasi-sinusoidal output to the DC system. The AC side current is thus also sinusoidal. Smoothing can be added to the DC system.

Description

Description and claims

Simple set-up without any losses due to the principle involved in the removal of Mains-frequency, largely sinusoidal current from AC or D & eh voltage networks and to convert the withdrawn electrical energy into galvanically connected DC voltage systems or DC voltage intermediate systems.

Electrical energy networks, especially those of highly industrialized ones Countries are increasingly affected by harmonic currents, which caused by power electronics devices.

Above a certain level, these harmonic currents interfere with both the operation of the energy networks themselves as well as other consumers connected there. It is thus the task of direct current systems or alternating and Three-phase systems with non-network frequencies require electrical energy from the supplying AC or three-phase voltage networks via network-frequency, largely sinusoidal Electricity and, if possible, to be drawn without any losses due to the principle.

This task is achieved with little of the invention presented here Effort solved.

In describing them, let us first focus on the extraction of energy AC voltage networks and only then on the corresponding aldc task in three-phase networks.

In addition, for the sake of clarity, a special embodiment should be made beforehand of the invention will be fully described by way of example. Additions, modifications and realizations with the help of other components will only be presented at a later point and explained.

FIG. 1 initially shows this exemplary embodiment, starting from the left schematically a feeding AC voltage network (1) with the voltage Uv which one after the other a differential voltage choke (2), an uncontrolled rectifier in bridge circuit (3), a push-pull converter with step-variable voltage translation (4) and a DC voltage system (5) with the voltage E are connected downstream.

The push-pull parallel converter contains one that is symmetrical about its center Autotransformer (6) with a total of 3 primary-side and 8 secondary-side taps.

The central lap on the primary side (7) is directly connected to the positive pole of the Bridge rectifier connected. The two external taps on the primary side (9) and (10) are each w turns from the center of the transformer remotely attached and separated from the collectors of two npn switching transistors (11) and (12), their emitters with the negative pole of the bridge rectifier are connected. The two inner taps on the secondary side of the autotransformer are each at a distance of w-1 turns of its center attached and separately led to the anodes of two diodes (13) and (14), their Cathodes are connected to the positive pole of the DC voltage system. The outer Secondary-side taps of the autotransformer are symmetrical in pairs in Distances of (w1 + w2), (w1 + + w2 + w3) and (W1 + w2 + W3 + W4) turns of its Center remotely attached and each separate to the anodes of six thyristors (15) to (20), the cathodes of which are connected to the positive pole of the DC voltage system are connected.

The driving alternating voltage uN has the amplitude u and the angular frequency . F. the following consideration will be the running time t or its related value r = £ ot t calculated from the last zero crossing of the alternating voltage uN and let it be assumed that the two switching transistors (11) and (12) and the six thyristors (15) to (20) can be influenced synchronously with the voltage uN in the following way: From E0 = C to # 1 r + 7r / 22 let the two transistors (11) and (12) be conductive and (as a result) all thyristors blocked.

At the (related) time # 1 = g + # / 22 become the left switching transistor (11) blocked (the right one remains conductive) and the extreme left thyristor (19) ignited.

At the (related) time # 1u = # + 2. # / 22 becomes the correct switching transistor (12) blocked and the left (11) switched on again, furthermore the outermost one right thyristor (20) ignited.

At the (related) time # 2 = # + 3 t- / 22 the left switching transistor becomes (11) blocked and the right one (12) switched on again, furthermore the middle one becomes of the three left thyristors, the thyristor (17) ignited.

At the (related) time g2u = f + 4.; r / 22 becomes the right switching transistor (12) locked again and the left one (11) switched on as well as the middle of the three right thyristor, the thyristor (18) ignited.

Proceed accordingly in a manner as shown in Table I below: Table I For related | Turn on ! Switch off 1 Ignition of of transistor (blocking) of thyristor Time iT xt 1 transistor 4 - 6 + ar T z, F7 r (44) («) f '? c) 6 3 t ({+ {} | 2 toe = g + 4 {{-fZ} For related switching on switching off ignition of of transistor (blocking) of 1thyristor Time i £ ot transistor IJI 5 C) 6 F rr j? j e -t t- E4 a, I * / 22nd Ts: 1 Kc ~ Ll, - rC = - Ciii I. z ef-E + == f + ^, f <v) {çeJ g rÆ 5 F {52 3 * zt i, '{2 i ß {for JI 73 '-r + st {} 4 { ~ .. = = rfU- E ", - erld, (,) B = E rr T fX, nJ ~ ~ =. (41) (/>.) according to t0T = 4 ic VI / cr-7) . () (?) 4 3, w (#i) { 7, 4, <r.; R 4ç} r / 7J) +62 . ~. . . rL 3 "+, = 4« 2 {r6) For related switching on switching off ignition of of transistor (blocking) of thyristor Time . 7 = cOt transistor l y C'f + i + (1?) r {+ ny r = efr 4 e -, 57 {+82 J} ~ JYII r = E + 1. e - zr 7cei = E + 4 Z7 = ZcT-alu, ~ / I f ,; = Flu (#) 5, (4) v f 7 (11) {e J z fi 7- (: 4) {~ {) ea &? + 4 <- ,, - fii) (-a) 6 {{{g, J c A -?. e + i3 for Ü?) et C {z / ZJ 4 f »'= g ~~~ For the following consideration it is assumed that the circumstance to be ensured later is that whenever at least one of the two transistors (11) and (12) blocks, the current i, in the alternating current feed line to the bridge rectifier differs from zero (iN + O) and as a result the current i flowing from the positive pole of the bridge rectifier to the center of the autotransformer is greater than zero (i> 0).

Under this condition the voltage has u from the center of the Autotransformer to the negative pole of the bridge rectifier in the interval from # 5 = # + 9 # / 22 to # '5 = # + 13 r / 22 (and accordingly in the interval from 75 + # = & + # + 9 # / 22 to # '5, + # = # + 71 + 13 # / 22), as long as the same two transistors (11) and (12) are blocked and the current i in equal parts from the diodes (13) and (14) is performed, the value of the voltage E of the DC voltage system (u = E). In the intervals from r + a / 22 to 5 = # + 9 # / 22 and from # '5 = # + 13 # / 22 to # '1 = + 21 # / 22 (as well as correspondingly in the intervals of # 1 +? = 6 + # + # / 22 to # 5 + # = # + # + 9 # # / 22 and from # '5 + 8 ~ = # + # + 13 # / 22 to #' 1 + e = g + # + 21 # / 22), as long as one transistor is conducting and the other is blocked is, the current i is shared by the currently conducting transistor and the last ignited thyristor or the diode of the opposite half of the autotransformer guided.

Thus the voltage is u from the center point of the autotransformer to the negative pole of the bridge rectifier a certain fraction # of the voltage E of the DC voltage system. This fraction is determined from the law of induction as the ratio of the number of turns w (from the center of the autotransformer to its primary-side external taps) to the sum of this number of turns w and that number of turns, which the secondary-side tap of the autotransformer, through which part of the current i momentarily flows out to the DC voltage system, has up to the center of the autotransformer.

For example, in the time interval from # 2 = # + 3; F / 22 to # 2u = # + 4 r / 22, the current i is carried by the right transistor (12) and the middle thyristor (17) of the left half. As a result, # has the value in this interval and the voltage u thus takes the value at. In the intervals from = = # to # 1 = # + # / 22 and E1 = + 21/22 to # 0 + r = 6 + # (and accordingly in the intervals from E0 + = 6 + +7 to r1 + F = # + r + r / 22 and from # '1 + g = 6 + # + 21 # / 22 to # 0 + 2 7F = CC + 2 #) as long as both transistors (11) and (12) are conductive and the current i - if it is different from zero - is carried in equal parts by the transistors, the voltage u from the center point of the autotransformer to the negative pole of the bridge rectifier basically has the value zero, regardless of whether i ~ and thus i are different from zero or not. This circumstance will nozh be used very advantageously.

Under the specified conditions and with a choice of the number of turns ratios of the autotransformer according to the following relations w1 = 0.088 w W2 = 0.227 w w3 0.523 w w4 = 1.677 w is thus obtained for the voltage u from the midpoint of the Autotransformer to the negative pole of the bridge rectifier sketched in Fig. 2 center Course. The value E = for the voltage E of the direct voltage system 0.9932 cos #. û ~ taken as a basis. Above this step curve u = u (#) is the course the voltage us of the feeding AC voltage system.

In addition to the assumptions made so far, the following is from the It was also assumed later that the current is in the AC feed line to the bridge rectifier in the (related) time interval from 1 = # + z / 22 to # '1 = + 21 # / 22 greater than zero, i.e. positive and in the time interval from # 1 + # = 6 + 1 + / 22 to t1 + it = # + a + 21 -r / 22 less than zero, i.e. negative is.

This has the consequence that the acting as a current-controlled switch Bridge rectifier (3) from his right AC connection (21) to his left AC connection (22) in the time interval # + r / 22 # r # # + 21 7r / 22 die Voltage UT = u (because in this time interval the current i ~ is greater than Is zero) and that this voltage uT in the time interval + + z + # / 22 # # # # + # + 21 # / 22 assumes the value uT = -u (because in this time interval the current i, is smaller than is zero).

The voltage uT between the two alternating current connections (21) and (22) of the bridge rectifier (3) thus has the curve sketched in FIG. 2 at the bottom. If the function given by this is subjected to a Fourier analysis, one obtains for the fundamental oscillation it contains with the (related) period duration 2 #, the voltage u1 entered in broken lines with the amplitude: û1 = E 1 / 0.9932 = û ~ .cos #. The harmonics contained in the voltage uT have the circular frequencies ## = #. # and the amplitudes where 9 = s 22 # 1 1 and # = 1,2,3 ... co.

The ordinal numbers # = 21.23; 43.45; 65.67; with the Amplitudes u1 / 21, u1 / 23; Ú1 / 43 ù1 / 45; u1 / 65, u; / 67; ....on.

With regard to harmonics it is of particular importance that on the one hand only fairly high ordinal numbers and thus high frequencies occur and on the other hand, their amplitudes are quite low. With regard to the fundamental u1 is to be noted that this in its amplitude (via the choice of E) and in its Phase position relative to the driving AC voltage u, (via the choice of 6) in a wide range Limits can be freely influenced.

The voltage uD at the differential voltage choke is determined according to FIG. 1 Its fundamental component uD1 = u ~ - u1 defines the fundamental i ~ of the current N in the AC line to the bridge rectifier. Their harmonic components uDç = -u cause harmonics in the current ia. However, these are - at least in the vicinity of the nominal operating state of the system - very much smaller than the fundamental, since the effective impedance of the differential voltage choke increases linearly with increasing frequency and the harmonics contained in uT have high frequencies and also small amplitudes.

For these reasons, only the fundamental vibrations are initially assumed in UD. > uT and the quantities uD1, u1 and i ~ 1 are considered.

Their general relationship is shown in Fig. 3a Vector diagram reproduced: Then the hurries. Current I ~ 1 of voltage U around 900 after and the voltage UD1 follows from the relationship UD1 Us Ua -D1 -One recognizes that via a suitable choice of the amplitude of the voltage U1 and its phase lag c with respect to the voltage U is the angle / by which the current I ~ 1 of the voltage UN lags, can be chosen freely within certain limits. For example can ratios can also be set, as shown in Fig. 3b. there is selected g = 200 and the fundamental amplitude of the voltage u1 between the two AC connections (21) and (22) of the bridge rectifier (3) the setting of the voltage E of the DC voltage system (8) determined so that the fundamental oscillation of the voltage uD at the differential voltage choke of the fundamental oscillation the voltage uT between the two AC connections (21) and (22) of the bridge rectifier lags behind by 900. Consequently is the fundamental oscillation of the current ts in the AC line to the bridge rectifier in phase with the fundamental oscillation of the voltage uT between the two AC connections (21) and (22) of the bridge rectifier.

The diagram in FIG. 4 shows these relationships according to FIG. 3 b the time curves of the voltage ur (23) of the feeding AC voltage system (top), the voltage u (24) from the center point (7) of the autotransformer (6) to the negative pole of the bridge rectifier (3) (middle), the voltage uT (2R) between the two AC connections (21) and (22) of the bridge rectifier (below) and the Current is (26) in the AC line to the bridge rectifier (again above).

Fig. 5 shows the course of the same quantities (u ,, u, UT and i,) for the case that the phase lag of the voltage U1 compared to the voltage U on 100 is withdrawn and the fundamental amplitude of the voltage u1 between the two AC connections of the bridge rectifier via the setting the voltage E of the DC voltage system is set again so that the fundamental oscillation of the current is in phase in the AC feed line to the bridge rectifier with the fundamental oscillation of voltage uT between the two AC connections of the bridge rectifier is located.

The two diagrams show that it is possible without difficulty the circumstances previously presupposed by a suitable choice of and E and in particular to ensure a suitable assignment of these two variables to one another. As assumed, is always when at least one of the two transistors (11) and (12) block the current i in the AC feed line to the bridge rectifier different from zero (i ~ + O) and consequently that of the positive pole of the bridge rectifier Current i flowing to the center of the autotransformer is greater than zero (i> O) In particular, the current i is in the AC line to the bridge rectifier in the (related time interval from r1 =! + r / 22 to #i = # + 21 # # / 22 greater than Zero, i.e. positive and in the time interval from r1 + # = # + # + / 22 to t1 + # =! +! + 21 # / 22 less than zero, i.e. negative. This latter circumstance (is > 0 from # 1 = 6 + # / 22 to # '- + 21 r- / 22 and i ~ <O from # 1 +; r = + 6 + # / 22 to T 'r 6 + # + 21 # / 22) is what is required for proper functioning of the must be complied with in the circuit according to FIG. 1, if this is in accordance with the table I operated. From the in Fig. 4 and Fig. 5 shown sketches it can be seen that thus for the zero crossings of the current iN (26) in the alternating current supply line the bridge rectifier is only stipulated that this is within certain Time intervals take place. The zero crossing from negative to positive has in the (related) Time interval from T = g - r / 22 to 7 = G + F / 22, that from positive to negative in the (related) time interval from r = # + 21 m / 22 to 7 = 6 + a F # / 22. The assignment of the two quantities e and E to one another and to the amplitude and phase position the voltage of the feeding AC voltage system does not have to correspond exactly the vector diagram of Fig. 3b take place. Rather, there is a certain area in which s and / or E can be varied without affecting proper function the circuit is affected. This insensitivity to the arrangement certain changes in parameters C and E will affect their practical implementation very beneficial.

Which are at twice the frequency of the feeding AC voltage system 2f = 2 / 2'r periodically repeating control of the transistors (11) and (12) and the thyristors (15) to (20) according to the table above can be easily connected to the AC voltage system synchronized Switching logic take place. The value E, which is the variable displacement of the various Switching times compared to the zero crossings of the voltage of the feeding AC voltage system and, as emerged from the diagrams in Fig. 4 and Fig. 5, the Determines the power drawn from the AC voltage system, this switching logic is controlled by given outside. Fig. 6 shows the arrangement of FIG. 1 after adding one such switching logic contained in the dashed box (27). This switching logic can be implemented in many ways.

In the example according to FIG. 6, it initially contains a guide RC element, consisting of the adjustable resistor (28) and the capacitor (29), whose Voltage of the voltage of the feeding AC voltage system by the over the size of the resistor (28) lags influencable angle g. This lead RC member are, via the impedance converter (30), decoupled with regard to their repercussions, a total of 18 delay RC elements, consisting of the resistors (31) and the Capacitors (32) connected downstream, the voltages of which correspond to the voltage of the feeding AC voltage system by the angles e + /. lag t / 22, / = 1 to 9 and 13 to 21.

The last delay RC link in this chain is another impedance converter (33) subordinated.

The outputs of the impedance converters connected downstream of the delay RC elements are each connected to a total of 18 comparators (34), their output voltages at each zero crossing of the capacitor voltage applied to the associated impedance converter (30) change their signs.

The outputs of these 18 comparators are linked to a logic unit (35) switched, which the two transistors (11) and (12) according to the further forward listed table on and off and - also according to this table - The thyristors (15) to (20) ignites.

The structure of this r linking unit (35) is so simple that it can be no further explanation is required.

With the current state of the art, the entire can with the dining AC voltage system synchronized switching logic (27), however, in a known, less more complex and at the same time more exact way e.g.

with the help of an oscillator, an electronic counter and a electronic read-only memory. Also allow such solutions it without difficulty, the angle e via the position of a potentiometer or to prescribe or change a control voltage from the outside. In addition, you can thus the switching points specified in the table above even then be adhered to very precisely if the frequency of the feeding AC voltage system (1) changed to a significant extent.

For compliance with those characterized by the phasor diagram according to FIG. 3b Ratios must then, if for the purpose of changing the alternating voltage system (1) the drawn power of the angle C is adjusted, also the voltage E of the absorbing DC voltage system to be adapted to the new conditions.

In the present example, the amplitude of the voltage between the both AC connections of the bridge rectifier (3) the value: ul = E / O, 9932 From the vector diagram according to FIG. 3 b it follows: u1 = uzv * cos Thus has for ratios in accordance with FIG. 3 b, the relationship E = 0.9932 us zip cos »to exist. For the The presented facilities are primarily values in the range of Orbis for # 200 significant. In this range, the term cos E varies in the range between 1 and 0.94. The required change in E thus remains within a range of only 6 t.

Their practical realization will depend on the specific application judge.

If, for example, the electrical Energy with the interposition of a DC power converter to a DC load - for example a battery to be charged - is supplied, E can be via the voltage transformation ratio this DC controller can be influenced accordingly. To clarify are In Fig. 7 a, the two terminals (36) and (37) are drawn again, to which in Fig. 6 the receiving DC voltage system (5) is connected. To this DC system (5) is now in Fig. 7a a DC chopper (38) with a variable voltage transformation ratio connected, which feeds a storage battery (39) at its output. Upper a change in the voltage transformation ratio of the DC chopper (38) the voltage E between the two connection terminals (36) and (37) of the DC voltage intermediate system (5) can easily be adjusted in the desired manner. It is useful to to make this adjustment via a controller, which is the desired value as the setpoint DC voltage Esoll, e.g. according to the above equation, i.e. according to Eso11 = 0.9932 u. . cos C, and which is the actual voltage E. between the two terminals (36) and (37) can serve as the actual value EiSt. For education des, 1 setpoint Esoll = 0.9932 ú û ~. cos 6 is the peak value ûs of the voltage of the feeding AC voltage system (1) and with 0.9932 and with multiply cos C.

You can do this, however. also very beneficial use of the fact make that the voltage on the capacitor (29) of the lead RC element in the switching logic (27) of FIG. 6 has the amplitude u co g (cf. the phasor diagram according to FIG Fig. 3 b), which after their detection then only with the constant factor), 9932 must be weighted in order to be able to be used as the desired target value.

The peak value of this capacitor voltage can either be via a simple peak value meter or - dynamically higher quality - via an electronic one Squaring of this tension, a subsequent removal of what is then contained AC component with twice the frequency (2f = 2 * / 2 r) of the feeding AC voltage system with the help of a so-called notch filter and a subsequent electronic root extraction be won.

Another method for setting the voltage E is based on of Fig. 7b described.

There is an example of the DC voltage system (5) a Inverter (40) connected and the voltage E of the DC voltage system is via the ones supplied to this system (or - in a corresponding manner - those supplied to this system withdrawn) power set or adjusted to the desired value. Will the supplied power increases, so E increases, this power is reduced, so E decreases.

In Fig. 8 a is in the supply line from the DC voltage system (5) a DC load (41) a continuously operating power transistor (42) switched on, the conductance of which is set or changed via its base current. it is regulated that E assumes the desired value.

As a final example of the change in E, FIG. 8 b shows a Arrangement in which in the supply line from the DC voltage system (5) to a DC power consumer (43) a small, electrically isolated DC chopper (44) is inserted, its Output also delivers its power to the direct current consumer (43). Upper a change in the voltage transformation ratio of the DC chopper (44) the voltage E of the DC voltage system (5) can be set or

can be adjusted so that it assumes the desired value.

So far it has been assumed that for the purpose of changing the the AC voltage system (1) drawn power primarily adjusts the angle s and the voltage E of the receiving DC voltage system then the new conditions is adjusted. Of course, the reverse is also possible. Included is used to change the power drawn from the AC voltage system primarily adjusts the voltage E of the receiving DC voltage system and then the angle g adapted to the new conditions. The latter can be like this, for example happen that the values E and ú are input to a function generator, which at its output the value E = = arc cos 0.9932 uw supplies, which in turn is a Switching logic is specified, those with the voltage of the feeding AC voltage system (1) is synchronized and which the two transistors (11) and (12) according to the switches on and off in the table listed above and - also in accordance with this Table - the thyristors (15) to (20) ignites. On the other hand, the one aimed at for C can Value can also be set indirectly, e.g. by setting the time Position of the zero crossings of the Current i (26) in the AC supply line to the bridge rectifier (see Fig. 4 and 5) relative to the voltage uT (25) between the two AC connections (21) and (22) of the bridge rectifier detected and by a uniform relocation of the transistor switching as well as the Thyristor ignition times relative to the voltage of the supplying AC voltage system is set or regulated so that the zero crossings of the current in the AC supply line to the bridge rectifier come to lie approximately in the middle of those time intervals, in which the voltage uT (25) decreases the value zero (cf. Figs. 4 and 5), because meanwhile both transistors (11) and (12) are conductive.

The same effect can be brought about by the fact that the switching logic, which operate at twice the frequency of the feeding AC voltage system 2f = 2co / 2'r periodically repeating control of the transistors (11) and (12) as well as the thyristors (15) to (20) corresponding to the temporal described above Performs one after the other, not with the feeding AC voltage system but - with the elimination of the time shift by the angle C - directly with the current iN is synchronized in the AC power line to the bridge rectifier. For this case becomes a first additional device required which ensures a start-up of the entire facility from its idle state. This can for example done in such a way that the switching logic mentioned for is = 0 of auxiliary pulses which is triggered by the voltage us of the feeding AC voltage system (1) are triggered (and compared to their zero crossings by the in a simple Function generator lagging approximately formed angle g) and that these auxiliary pulses for is + 0 are suppressed.

A second additional device must ensure the stability of this control principle be secured in such a way that in the event of a power influence on the voltage E of the receiving DC voltage system according to the phasor diagram Fig. 3 b sets the angle g belonging to this value E and the positive and negative Half oscillations of the current iw in the alternating current feed line are a mirror image Show course. For this purpose, for example, the direct component of the current i, in the AC supply line are monitored and then, if this is of the desired value Deviates from zero, via a delay in the positive or negative half oscillation corresponding synchronization pulses for the switching logic can be corrected.

For the embodiment of the invention described so far are in The following additional additions and modifications are presented, which one after the other the output circuit, the input circuit, the push-pull parallel converter with stepped variable Voltage transmission, the definition of its parameters (tapping ratios as well as Switching times and thus heights and widths of the voltage levels) and finally affect the entire circuit configuration. In the DC voltage or DC voltage intermediate system (5) a total current is fed in by the arrangement described, which the desired direct component, plus a considerable alternating component with twice the amount Frequency (2f = 2/2 g) of the feeding AC voltage system (1) and finally still contains an infinite number of harmonics with a smaller amplitude.

It is therefore advisable to connect parallel to the input of the DC voltage or DC voltage intermediate system a shunt capacitor and a suction filter to switch for twice the frequency of the feeding AC voltage system.

Fig. 9 shows such an arrangement with a shunt capacitor (45) and a suction filter (46) consisting of a series connection of a capacitor (48) and a throttle (49).

In order to supply the power to the DC voltage or

To be able to completely prevent the DC voltage intermediate system (5), it may be useful to perform all valves leading there in a controlled manner, that is to say to replace the diodes (13) and (14) (see FIGS. 1 and 6) with thyristors and in normal operation of the circuit, these thyristors ignite each time they should take over the current management. Fig. 10 shows such an embodiment of the Push-pull parallel converter with step-variable voltage ratio (4) after replacement the diodes (13) and (14) through the internal thyristors (50) and (51).

A complete suppression of the power supply to the DC voltage or DC voltage intermediate system (5) can of course also in the input circuit brought about e.g. by not having the input rectifier in the bridge circuit (3) is carried out uncontrolled but half or fully controlled or that it is a thyristor downstream or a three-electrode alternating current switch (triac) is connected upstream.

11 shows an example of such an embodiment of the input rectifier (3) with a downstream thyristor (52), which in normal operation of the circuit is kept conductive before the system is put into operation and when it is shut down but no longer receives any control current.

As can be seen easily from the diagrams shown in FIGS. 4 and 5 is, it is unimportant with correct operation of the arrangement whether the differential voltage choke (2) Before or after the uncontrolled rectifier arranged in a bridge circuit is.

Fig. 12 shows an embodiment in which the order of these Components compared to that shown in Fig. 1 is interchanged. Here follows on the feeding AC voltage network (1) so initially the rectifier in a bridge circuit (53) and then the differential voltage choke (2), to which then again on the right the push-pull parallel converter with step-variable voltage ratio to be connected Has. Here, too, would be an uncontrolled one for the rectifier in the bridge circuit (53) Execution used, then this would no longer - as desired - as a current-controlled but work as a voltage-controlled switch and thus function correctly prevent the circuit.

In order to avoid this, the differential voltage choke must be installed in the described installation behind the input rectifier in bridge circuit (53) the latter either fully or run semi-controlled and to carry out its ignition in such a way that the Current i in the AC line can only reverse its direction when it has previously become zero. This can be done in a very simple way by that the non-current-carrying branch is only ignited when the current in the previously current-carrying branch has decayed to zero.

The input rectifier shown in FIG. 12 is an example in the bridge circuit (53) designed as a symmetrically half-controlled bridge, in which used for the two cathode-coupled valves (54) and (55) thyristors are.

For capacitive-symmetrical decoupling of the push-pull converter with stepped variable voltage transmission and the downstream systems from the feeding AC voltage system, it can be very useful to use the differential voltage choke split and the resulting partial throttles symmetrically in the two supply lines to insert the push-pull parallel converter with stepped variable voltage translation, either before or after the input rectifier.

13 shows an example of an embodiment with a two-part differential voltage choke, at which the two partial chokes (56) and (57) between the feeding AC voltage system (1). and the uncontrolled rectifier in the bridge circuit (3), ie "before" the latter are arranged.

FIG. 14 shows the course of the variables indicated in FIG. 1, u, uT and iN in the event that the phase lag of the voltage U1 compared to the Voltage UI (cf. FIG. 3) is reduced to approx. 30 and the fundamental oscillation amplitude the voltage u1 between the two AC connections of the bridge rectifier again so determined by setting the voltage E of the DC voltage system is that the fundamental oscillation of the current ia in the AC feed line to the bridge rectifier be in phase with the fundamental oscillation of the voltage uT between the two AC connections of the bridge rectifier is located.

It is easy to see that if (to values under 3 °) the above-mentioned condition, according to which the current i ~ in the alternating current supply line to the bridge rectifier in the (related) time interval from # 1 = # + # / 22 to # '1 = e + 21 # / 22 greater than zero, i.e. positive, and in the time interval of r1 + Ir = " + # + / 22 to '' + # = g + # + - / 22 less than zero, i.e. has to be negative, is no longer observed.

As a result, the would then act as a current-controlled switch Bridge rectifier (3) from its right AC connection (21) (cf.

this Fig. 1) against his left AC connection (22) not more in the entire time interval # + / 22 - # f # + 21 # / 22 have the voltage uT = + u (because the current i in this time interval is not always greater than zero would be) and accordingly this voltage uT would not be in the entire time interval r + # + r # / 22 # r # + 7r + 21 »- / 22 assume the value uT = -u (because in this time interval the current i ~ would then not always remain less than zero).

Then the voltage uT would be as shown in FIGS. 4, 5 and 14, in the positive and negative half-oscillation from a simple, five-stage each Pyramid lost existing course.

The harmonic content of this voltage would be themselves increase significantly and thus also that of the current i in the alternating current feed line to the Bridge rectifier. So should be for the purpose of a strong reduction in the dining AC voltage system (1) removed and fed to the DC voltage system (5) electrical power is the phase lag of the voltage U1 compared to the voltage Us (see FIG. 3) can be reduced to less than 10 without changing while the curve shape of the voltage uT changes considerably, the inductance must first be the differential voltage choke can be increased. This can be done with little effort e.g.

can be realized in such a way that corresponding to the representation in Fig. 15 two throttles (58) and (59) are provided, which for larger values of the Fundamental oscillation of the current in the AC line to the bridge rectifier (3) can be connected in parallel via the two-pole changeover switch (60) (then located the changeover switch, as shown in FIG. 15, is in position A) and with stronger Reduction of the electrical power taken from the feeding AC voltage system (1) Power can be connected in series (then the changeover switch (60) is in position B). Corresponding can of course also with a single, with more than a coil provided throttle can be effected.

On the other hand, a premature zero crossing of the current i in the AC feed line to the bridge rectifier (see Fig. 14) also through this avoid that, as already mentioned earlier, the input bridge rectifier not uncontrolled but fully or semi-controlled and in the related Time interval ## = 0 to E1 r6 E 2> r to # 1 + 3 # etc. that branch of this bridge is released, which a current i> O in the AC power line to the Bridge rectifier and in the related time interval ## = 7t to # 1 + 2r (, 3ir to # 1 + 4 h- etc. the other branch of this bridge is released.

An example of this is the input rectifier in a bridge circuit in FIG (61) designed as an asymmetrical, semi-controlled bridge, in which for the two Valves (62) and (G3) of the right branch thyristors are used.

In the arrangement fully described above, in of the staircase voltage uT harmonics with the frequencies fy = f #, where = P.22 + -1, + = 1,2,3 ... ##. f is the frequency of the voltage of the feeding AC voltage system, usually has the value 50 Hz in Europe and 60 Hz in the USA Connection the circuit described to the European standard network occur in uT harmonics with the frequencies 1050 Hz, 1150 Hz, 2150 Hz, 2250 Hz on. These harmonics in uT cause harmonics in the current i ~ in the AC power line to the consumer, which have the same frequencies exhibit. Due to the regulations of the energy supply companies, the maximum permissible effective values of these currents are limited directly or indirectly. Currently concern these regulations primarily cover the frequency range from 100 Hz to 2000 Hz of the aforementioned harmonics in current i are in particular those with the Frequencies 1050 Hz and 1150 Hz disturbing.

It is therefore obvious that these harmonics are not only caused by the Damping the differential voltage choke, but also through the appropriate blocking filter in the input circle. 17 shows an example of one from the bridge rectifier (3) and the differential voltage choke (2) existing input circuit, in which the differential voltage choke (2) is followed by two blocking filters (64) and (65) are. These notch filters each consist of a parallel connection of a small one Choke (66) and (67) and a capacitor (68) and (69) and are on the frequencies the special one disturbing harmonics in the current iQ (here 1050 Hz and 1150 Hz). With harmonics that are close together, the corresponding effect also through a single, through parallel connection one Bring about the ohmic resistance of a broadband blocking filter.

Harmonics in the current i in the AC line with frequencies above 10 kHz, in particular above 150 kHz, are primarily for this reason undesirable because they cause interference in radio and television reception can be. To feed harmonics of this frequency range in the current i aom To keep the AC voltage network away, it is recommended, as shown in the illustration 18 in the connection line from the feeding AC voltage system to the bridge rectifier in addition to the differential voltage choke, an input low-pass filter (70) is to be added.

This input low-pass filter (70) is the one shown in FIG Exemplary arrangement of two - small - longitudinal throttles (71) and (72) and two small shunt capacitors (73) and (74).

The course already sketched in FIG. 2, center, is again shown in FIG. 19 the voltage u from the center of the autotransformer to the negative pole of the bridge rectifier shown how it results when the arrangement shown in Fig. 1 accordingly Tabel I operated. This step curve u = u (r) is, as shown in FIG. 19 or the table I can be seen immediately, for the abscissa values r z = # + # / 2, r = E + 2 # / 2, Z = 6 + 3 # / 2 etc. axially symmetrical and is therefore due to its course in the (related) Time interval # = <S to 1 = # + # / 2 already fully characterized. In this (related) time interval, the voltage u has the course of a five-step, ascending stairs. In particular, u = 0 from # = # to # = # +, u = y1 from # = # + to # = # + ß2, u = Y2 from # = # + ß2 to u = y3 + u = y3 from Z = # + to t = C + 6? 4, u = 4 from # = + # / L? 4 to r = C + 35, and u = y5 from # = # + ß5 to # = # + # / 2 (see Fig. 19).

As can be seen from Table I, the voltage levels y1 up to y4 (i.e. not on the basic level u = 0 and not on the final level u = y5) respectively in the middle of the relevant time interval (e.g. at voltage level y1 at the - related - time F1u = # + 1/2 (ß1 + ß2)) the switching state of the in Fig. 1 on transistors connected to the left and right sides of the push-pull part transformer (11) and (12) and thyristors (15) to (20) symmetrically to the center tap of the Push-pull autotransformer swapped (so is e.g. at the voltage level 31 in the - related - time interval from r = + Äi to 2-lu = + 1/2 ((ß1 +! 32) the right one Transistor (12) and the left thyristor (19) conductive and in the subsequent time interval from # 1u = # + 1/2 (/ 1 + 42) to r2 = 6 + / 52 the left transistor (11) and the right one Thyristor (20)).

If this mishandling of the switching status of the left resp. right side of the push-pull part transformer connected transistors and thyristors not only in the middle of the time interval belonging to the voltage level in question made, but, starting with the switching on of this voltage level in equidistant Time intervals, which are capable of the time interval belonging to this voltage level division by a whole, even number z (z> 2), then with increasing values of z while accepting a higher switching frequency a drastic one Reduction of the induction stress of the push-pull part transformer or a significant reduction of the same can be achieved. Since the induction stress of the push-pull autotransformer differently at the various voltage levels is large, it can be useful to use the whole, even number z for the various Choose levels of different sizes. The latter can be even recommend with regard to the noise development of the arrangement.

As can be clearly seen from FIG. 19, if one is at the design of the push-pull economy converter from the winding number ratios mentioned at the beginning goes off and the step voltages Y1 bis only by the condition o Z 1 c 32 < y3 <y4 <Y 5 ~ E and if one restricts the - related - switch-on time intervals 31 to ß5 of the various levels of r = not specified in Table I, but these switch-on time intervals (from r =) only by 0 <ß1 <ß2 <ß3 <ß4 <ß5 <# / 2 restricts, over a total of 10 degrees of freedom, which are e.g. available in this way can that on the one hand the desired fundamental oscillation of the voltage uT between the two AC connections (21) and (22) of the bridge rectifier results and on the other hand the direct or indirect regulations of the energy supply companies with regard to the maximum permissible effective values of the harmonic currents in the AC feed line can be met with the smallest possible throttle. Included E.g. a step curve u = u (#) with ß1 = 5,380; 42 ~ 13,800 33 = 22,930 ; β4 = 34,600; / 35 48,460 and y1 = 0.1392 û1; Y2 = 0.3614 µA1 ; = 0.4901 Ü1 y4 = 0.6846 uA1; y5 = 0.9164 u1 (= E), as shown in Fig. 20 above is to prove to be particularly cheap. At the bottom of Fig. 20 is the associated voltage UT sketched between the two AC connections of the bridge rectifier.

A Fourier analysis carried out for this shows that now no longer only harmonics with the ordinal numbers $ u 22 + 8 = 1,2,3 ... # occur, but all harmonics with odd ordinal numbers, but these with so low amplitudes that those issued by the Association of German Electrical Engineers (VDE) Regulations 0838, which determine the effective values of the various harmonic currents limit indirectly, adhered to with a particularly small differential voltage choke can be.

The aforementioned heights of the voltage levels y1 to y5 place the Number of turns ratios of the push-pull autotransformer fixed (w1 = 0.33f6 66 w w2 = 0.5312w 3 2 = 0.5312w 4 w3 = 0.6659w; w4 = 4.0476w, see Fig. 1) and the step switch-on intervals g1 to determine the time intervals with which the individual voltage levels after the zero crossing of the fundamental voltage uT must be switched on. It is easy to see that one has the above 10 degrees of freedom for the course of the Step voltage u (see FIG. 19) in each case in such a way that the boundary conditions set for the application in question to be met in the best possible way. The number of voltage levels can of course also be added s and thus also the number of step switch-on intervals increased or in the interest a reduction in effort can also be reduced. In the circuit according to Fig. 1 is the number of taps on the secondary side of the push-pull autotransformer (6) (and thus also the number of thyristors) accordingly to increase or to Reduce.

If, as just explained, the switching status of the transistors connected to the left or right side of the push-pull part transformer and thyristors not only in the middle of the voltage level in question Time interval, soiidein, starting with the switching on of this voltage level, at equidistant time intervals from the one belonging to this voltage level Time interval by dividing it by a whole, even number z (z - 2), So it makes sense to not only do this within the switch-on interval of a stage corresponding level value but also the preceding and the following Set the step value in such a way that within the first half of time interval j r belonging to the relevant voltage level at one or more Digits during the - related - time periods g (g are positive, whole, even Numbers and g c z) the previous step value is set and that within the second half of the time interval belonging to the voltage level in question for at one or more places during the - related - time periods g ## / # der the following step value is set.

21 shows an example of a stepped curve UT with the steps y1 to 5, in which within the first half of the voltage level in question corresponding time interval once to the level value of the following voltage level is switched over (for the - related - duration g -) and for which within the second half of the time interval belonging to the voltage level in question each time it switches to the level value of the subsequent voltage level becomes (for the - 'related - duration g> where both z and g for the different Steps or step halves can have different values). So you can either the regulations issued by the energy supply companies or other associations, which are the rms values of the various harmonic currents indirectly limit, can be complied with with an even smaller differential voltage choke or it can be the number of stages and thus the effort for the push-pull parallel converter be kept smaller, since the harmonics in the staircase voltage uT on this Way can be further reduced. As in the others described so far Examples are the quantities E, the voltage of the receiving DC voltage system, and £, the angle by which the fundamental u1 of the staircase voltage uT der Voltage us of the feeding AC voltage system lags, by way of a controller and / or control so that on the one hand the feeding AC voltage system the desired electrical power is withdrawn and the receiving DC voltage system is supplied and that, on the other hand, the current i in the AC power line to the Bridge rectifier always and only goes through zero when the voltage between the two input terminals of the push-pull converter has the value zero.

For some considerations on overload protection of the invention The device will come back to the embodiment of FIG.

There are both high voltages in the feeding AC voltage system as well as incorrect specifications from the control system (in particular due to to large values of e and too small values of E) or by faulty ones triggered by this Control of the transistors (11) and (12) or the thyristors (15) to (20) in particular the two switching transistors (11) and (12) endangered.

As can easily be seen from FIGS. 1 and 4, recommends In the event of an impending, incipient or existing overload, both immediately To put switching transistors (11) and (12) into the blocking state and possibly additionally to ignite all thyristors (15) to (20).

Then the two switching transistors (11) and (12) do not carry any current more and the voltage u takes the value of the voltage E of the receiving DC voltage system (5) and can therefore only rise as quickly as this, with its rate of rise through the differential voltage choke (2) and the parallel to the input of the DC voltage system (5) lying transverse capacitor (45) (cf. FIG. 9) is limited and - if required - can also be limited by the fact that the rectifier in Bridge circuit (see again Fig. 1) as half-controlled or fully-controlled Bridge carried out and not in the event of impending, beginning or existing loading more is released.

The protective measures described are supported by a arrangement to trigger which an impending, beginning or existing overload reliably and registered quickly. So it can be useful to take these protective measures in general to be triggered when the peak value of the voltage us of the feeding AC voltage system (1) or the current is certain upper limit values in the AC supply line exceed. In particular, this protection may not be selective enough if if the overload of incorrect control of the transistors (11) and (12) or the thyristors (15) to (20) goes out. As shown in FIGS. 1 and 4 immediately it is evident that a faulty control of the transistors (11) and (12) or the thyristors (15) to (20) (and also a high voltage in the feeding AC voltage system (1)) when it threatens to become dangerous, if the voltage is too high the differential voltage choke (2). It is beneficial after that that Protective measures then trigger when the amount of the instantaneous value of the voltage uD has reached a certain upper limit value at the differential voltage choke.

From Fig. 4 it can be seen that the voltage uX of the feeding AC voltage system (1), the current i in the AC line and thus also the voltage uD the differential voltage choke certain switching states of the push-pull converter assigned are. The selectivity of all three protection trips can therefore be further increased in that the various switching states of the push-pull converter were determined maximum permissible amounts of the sizes us, iw or

assigned and the protective measures are triggered when in a switching state of the push-pull economy converter, the assigned maximum amount of a of the three quantities u, iw or is exceeded.

Finally, it is of course also possible to reduce the stress on the in primarily endangered transistors (11) and (12) together or preferably to be monitored individually, in that their collector or emitter currents (the latter possibly together) or the collector-emitter voltages applied to them when switched on can be detected. If one of these stress parameters exceeds one for it individually set limit value, the protective measures described above are implemented triggered.

Largely independent of the type of triggering of the protective measures the re-enabling of the device according to the invention is expediently carried out if, on the one hand, the overload signal is no longer a critical operating condition and on the other hand since the overload protection trip a finite non-zero time interval has elapsed.

In the following are a few thoughts on the implementation of the push-pull parallel converter connected.

For this purpose, let us first refer to the basic representation of this push-pull parallel converter (4) in Fig. 1 reference. In the case of a five-step staircase curve the chronological sequence of the switching states of the transistors (11) and, (12) represented by Table I. It is found there that at very many points in time (e.g. z = 1u to 2 '2u) turn one of the two transistors off and the other is set. It should be noted that these switching processes have finite time intervals take up, i.e. run at a limited speed. Furthermore is It should also be noted that the switch-on process is usually completed more quickly than the switch-off process that the push-pull autotransformer (6) finite, from zero has different winding capacities and inductances and that also the Switch-on and switch-off times of the thyristors (15) to (20) and the diodes (13) and (14) are finite. This first suggests the control of the transistors (11) and (12) to unfold from each other in such a way that the shutdown of the one Transistor (and the switch-on process of the associated winding half connected and then current-carrying thyristor or diode element) is already completed before the switching on of the respective other transistor begins.

With regard to switch-on and switch-off relief networks to be expediently used for the switching transistors (11) and (12) it is even advisable to control the of the transistors (11) and (12) to unlap even further, such that the switching on of one transistor only begins when the switching off of the other transistor is already fully completed and following it a finite time interval on the order of 0.1 10 6 sec to 10, 10'6 sec has passed. The aim of this measure is to reduce that part of the switch-on load of the one transistor, which from the charging of the switch-off discharge capacitor of the other transistor results to be kept as small as possible.

To explain the aforementioned on and off relief networks for the switching transistors, the push-pull converter from FIG. 1 is sketched again on the right in FIG. 22 after its switching transistors (11) and (12) have each been provided with an on and off relief network. Lossy discharge networks were used here as an example, which in turn consist of a limiter choke (75), a switch-off discharge capacitor (76), a charging diode (77), a discharge choke (78), a discharge resistor (79), a limiter diode ( 80) and a common Zener diode (81) exist. The function of these relief networks is easy to see. When one of the two switching transistors (11) and (12) is switched on, the associated switch-off relief capacitor (76) is discharged aperiodically to zero capacitor voltage via the associated discharge choke (78), the associated discharge resistor (79) and the transistor; the limiter choke (75) limits the rate of rise of the main current and thus the load on the transistor when it is switched on. The next time this transistor is switched off, its collector voltage does not rise to significant values despite the presence of the limiter choke (75) and finite winding inductances of the push-pull part transformer (6) when the collector current through this transistor has already become zero, as the one caused by the limiter choke (75 ) after the transistor has been switched off, flowing current flows via the charging diode (77) into the previously discharged switch-off relief capacitor (76) and its voltage can only increase steadily in the process; The limiter diode (80) prevents the switch-off discharge capacitor (76) from charging to higher voltage values than the sum of the Zener voltage of the Zener diode (81) and the voltage E of the DC voltage system. (The dimensioning of the inductance of the limiter choke (75) is expediently done so that at maximum current through the limiter choke of the transistor to be switched off, the energy contained in the limiter choke charges the switch-off relief capacitor (76) after the transistor has been switched off just enough for the Zener diode (81) just does not respond; with a smaller current through the limiter choke of the transistor, the switch-off relief capacitor is then recharged when the opposite transistor is switched on under additional load, but this can be accepted because the current through its limiter choke is then also smaller.) 1 with the number of turns ratios w1 = 0.088 w, w2 0.227 w, w3 = 0.523 w, w4 = 1.677 w and thus W1 + W2 + w3 + W4 = 2.515 w occurs the fact that the connection points of the outermost Thyristors by a significantly higher number of turns n away from the center of the push-pull part transformer than the connection points of the transistors are quite disruptive in appearance. On the one hand, this makes the maximum voltage between the two winding ends of the push-pull autotransformer uncomfortably high in relation to the voltage E of the DC voltage system As a result, the desired low-leakage design of the push-pull autotransformer is made very difficult; on the other hand, due to its high number of turns, the leakage inductances of the outermost partial windings are fundamentally very high and, thirdly, the size of the push-pull autotransformer is undesirably high - again due to the high number of turns of the outermost partial windings.

With the aid of a further key concept of the invention, however, this problem can be solved in a simple manner. Reference is again made to FIG. 1 for its explanation. The same ratio can be used there of the push-pull part transformer, which occurs when the left transistor (11) and the extreme right thyristor (20) are energized, even if the outermost thyristors (19) and (20) and their partial windings are omitted, the Transistors (11) and (12) diodes are inserted, the cathodes of which are connected to the collector of the associated transistor and that the two halves of the winding of the autotransformer (6) are additionally symmetrical at a distance of Windings are tapped from its center point and the anode of a thyristor is connected there, the cathode of which is connected to the collector connection of the transistor connected to the same winding half, and that a switching state is brought about in which the left transistor (11), the left primary thyristor, whose cathode leads to the collector of the left transistor (11), and the now outermost right thyristor (18) are live.

23 shows the push-pull parallel converter after the described removal the outermost secondary thyristors (19) and (20) and insertion of the diodes (82) and (83) in the collector leads of the transistors (11) and (12) and after Insertion of the thyristors (84) and (85) between the new primary-side winding taps on the push-pull autotransformer (6) at a distance of wI turns from its center point and the collector connections of the transistors belonging to the same winding half.

In order to obtain a curve for the staircase voltage uT with this arrangement as shown in FIG (18) synchronously to the voltage u of the feeding AC voltage system according to the following table II: Table II Table II Initial state: At the time # = # 0 = #, let (11) and (12) be conductive! For related switching on | Switch off ignition of Time r = Z t of transistor (blocking) of thyristor Transistor i 4 e 22 ~ {{, r / {} 22nd T r = K ') {<} t tv { G 3aa to92 {f + i} C4-2y §-27- {çJ (i) Ir r3 = e + 6 ,?) 61 <) (is) 7 /: ri) t> .2) Ü;) 74 = C4? 7 6fi) t42 2 (ii) fi) T («) "U () = SX (11) {«?) -, ~ t (s + z - {«+ J (/?) t4J Yes -7- (l) (44) (- / 9.) e + a: ri + (1?) '(/ d') (+ tJ <> j.,. "i"! = 06 tt ß {<dJ At (11) (1?) 1 22 - - - ----- - - Table II continued For related switching on! Switch off ignition of Time r = location of transistor '(blocking) of thyristor transistor ~ 7; + + F = ttr + dr + HP) aac / fdnRJ + + r = {t (1?) 2 I 6) eateV (?) G + p = 6+ F +? + T3T (#?) (11) () tqy f ++) {+ t} fi?) 5; 1 + (+ r + b (#J J? 7+ R 6.4) {+9 {v6) J4 23 t + = c + 7 # (44) 7 & + = {«) ~ (il) (1?) & r e + (4) a5t 3Rtt ETC ~ S ~ = 7 - '+ tqR2 {+ «J {«? J ~ 32 z 7E {NJ r { 9 ~ 7 g {~} {«} {86Y g JF {v? J (ii) (19) J ~ + z + 7F (1) (#) Ezt zr J / "C / t $ S} <+ {+ «J / :?) / ~ cm- /, f / + 7 {{«8J CA ns ~ 109 / 01i- - Of course, the two primary-side thyristors (84) and (85) in FIG. 23 can also be replaced by correspondingly controlled transistors. Since these can also be switched off via their control electrode, their emitter connections then do not necessarily have to be connected to the collector connections of the transistors (11) or (12), but can also be connected directly to the negative pole of the bridge rectifier. The arrangement that then arises is sketched in FIG. The essence of the extended key concept of the invention presented with FIGS. 23 and 24 is the fact that the outer taps of the autotransformer connected in its center to the positive pole of the bridge rectifier are divided into two groups, the taps of each of these groups being symmetrical are distributed over both winding halves, and that the two inner taps of the first group are each connected to the anode of a diode or a thyristor, the cathodes of which are connected to the positive pole of the DC voltage system, and that the further outside The taps of the first group are each connected to the anode of a thyristor, the cathodes of which are connected to the positive pole of the DC voltage system, and that with regard to the taps of the second group, the procedure is either such that the two most inner taps are each individually with the collector connection each e Ines switching transistor are connected, the emitter connections of which are connected to the negative pole of the bridge rectifier, and that the taps of this second group located further outside are each connected to the anode of a diode, the cathodes of which are each connected to the collector connection of a switching transistor, whose emitter connections are connected to the negative pole of the bridge rectifier, or that with regard to the taps this second group is proceeded in such a way that the two most outer taps each with the anode, one diode each and the taps further inside of this second group each are each connected to the anode of a thyristor, and that the cathodes of these diodes and thyristors are connected within each circuit half together with the collector terminal of a switching transistor and that the emitter terminals of these two switching trans are connected together to the negative pole of the bridge rectifier. In this way it is ensured that the electrical connection between the taps of the autotransformer belonging to the second group and the negative pole of the bridge rectifier can be interrupted at any time and for the two winding halves independently of one another by switching off the transistors, and that if all the taps of the autotransformer from the negative pole have previously been interrupted of the bridge rectifier are electrically isolated, an electrical connection can be established between any tap belonging to the second group and the negative pole of the bridge rectifier.

This in turn is the prerequisite for that between the center point voltage of the autotransformer and the negative pole of the bridge rectifier u can be generated from the shape as shown in FIG.

In addition to the switching states listed in Table II, the Arrangement according to FIG. 23 and of course with that according to FIG. 24 as well more are brought about; in the arrangement of Fig. 23, for example, that in which the right, internal secondary thyristor (16) and the left transistor (11) as well the left primary thyristor (84), its cathode to the collector of the left transistor (11) are live. Then this results for the push-pull part transformer a gear ratio WI wI + w1 + w2. So, for example, can be explained in further 12 above Example with the steps = = 0.1392 µA1; Y2 = 0.3614 û1; J3 = 0.4901 û1 y4 = 0.6846 u1; y5 = 0.9164 u1 (= E) (this includes the number of turns: w1 = 0.3386 w w2 = 0.5312 w; w3 = 0.6659 w and wI = 0.2751 w) also the level 3 = 0.2202 û1 can be set without the power section of the push-pull converter must be changed. The reverse can be done with freely selectable number of turns ratios w 1 / w, w2 / w, w3 / w and wI / w as well as switch-on intervals (relative to # = #) ß1, ß *, ß2, ß3, ß4 and / ß5 e.g. a curve of the voltage u from the center of the autotransformer lead to the negative pole of the bridge rectifier, as shown in FIG is.

You can see immediately that you are doing this for the formation of the curve shape the voltage u from the center of the autotransformer to the negative pole of the bridge rectifier has a total of 11 degrees of freedom (namely the six switch-on intervals ß1, ß * ß2, ß3, ß4 and ß5 as well as the five voltage levels y1, y2, y3, y4 and y5, which the voltage level y * is assigned by y * = y5 - y2 y1y3y5y2 + y3y1 - y3y2 - y2y1 is), which can again be used, for example, in such a way that on the one hand the desired fundamental oscillation of the voltage uT between the two.

AC connections of the bridge rectifier results and on the other the direct or indirect regulations of the energy supply companies with regard to the maximum permissible rms values of the harmonic currents in the AC supply line can now be met with the smallest possible throttle.

Finally, in the case of the arrangement according to FIG Way, with the one according to Fig. 24) still another switching state can be brought about, which is not yet listed in Table II, namely that in which e.g. the right secondary diode (14) and the left transistor (11) and the left primary thyristor (84), the cathode of which leads to the collector of the left transistor (11), live are. Then there is a further transformation ratio WI for the push-pull transformer nis, namely wI, via which in a, wI + w1 to the above-described analog Way can be decreed. However, this can result in considerable stress the push-pull part transformer and the transistors and thyristors used result, which may suggest that this last-mentioned switching state should not be used.

Overall, efforts will be made in each case to the one described at the beginning To solve the task in the most economical way possible. It can prove to be expedient to highlight compared to the expense of thyristors and taps on the push-pull transformer that described with Fig. 23 to decrease or increase.

Fig. 26 shows a lean version of the push-pull parallel converter with a total of only 4 thyristors (two on the primary and two on the secondary side), while in Fig. 27 a slightly more complex version with a total of 8 thyristors (each 4 on the primary and on the secondary side). The latter allows the Setting of a total of 11 conversion ratios E of the push-pull autotransformer (0, w w w, 1 w + w1 + w2 + w3, w + w1 + w2, w + w1, 1; wI + wII, wI + wII, wI + wII; wI, wI + wII + w1 + w2 + w3 wI + wII + w1 + w2 wI + wII + w1 wI + w1 + w2 + w3, wI, wI;) five of which are completely free wI + w1 + w2 w1 + w1 are selectable and at the same time determine four more, while the two remaining (0 and 1) are fixed anyway. On the other hand, you can use the possible 10 switch-on intervals be completely free. With regard to the voltage stress of the push-pull converter as well as the transistors, thyristors and diodes it can be here especially recommend that one or more of the fundamentally possible To forego switching states.

A large number of switchable voltage levels can also be used realize in another way, namely by having two push-pull parallel converters of the type described are operated in parallel via an AC suction throttle.

Fig. 28 shows such an arrangement in which the transformer centers two push-pull parallel converters (86) and (87) of the simplest version - with two each Primary transistors (88) and (89) or (90) and (91) and two secondary diodes each (92) and (93) or (94) and (95) - to the two external connections of a suction throttle (96), the center of which then takes the place of the central tap (7) of the push-pull autotransformer according to FIG. 1 occurs and therefore with the positive pole of the Bridge rectifier (3) is connected. The emitter connections of all four transistors (88) to (91) are connected to the negative pole of the bridge rectifier (3). the Both AC connections of the bridge rectifier (3) are as in Fig. 1 below Interposition of a differential voltage choke (2) with the feeding AC voltage network (1) connected. This arrangement according to FIG. 28 now allows the setting of a total of 6 gear ratios u / E (0.1 / 2 w / w + w1, w / w + w1, 1, 1. w + 1, 1) of those two completely 2 2 w + w1 2 are freely selectable and at the same time 2 more while the other two (0 and 1) are fixed anyway. About the possible 5 switch-on intervals can be freely used again.

For the formation of an appropriate curve shape of the voltage u vom You have the center point of the suction throttle (96) to the negative pole of the bridge rectifier so a total of 7 degrees of freedom at hand (namely e.g.

the two voltage levels y2 and y5, which are then the voltage levels y1, Y3 and y4 by virtue of y1 = y2, y3 = y5 and y4 = y1 + y 2 2 are assigned as well the five switch-on intervals ß1, ß2, ß3, ß4 and ß5).

With this arrangement a curve of the voltage u from the center point get the suction throttle (96) to the negative pole of the bridge rectifier (3), like basically shown in Fig. (19) are the four switching transistors (88) to (91) synchronous with the voltage etc. of the feeding AC voltage system e.g. according to the following table III.

Table III Table III Let the four transistors (88, 89, 90 and 91) be conductive from # = # to # = # + β1. For related activation of shutdown Time r = oe t transistor (blocking) of transistor e +, / BB c + l'34 + f- # dt! 8) () Lt g + 34 * - () r6) 9) 4th e + p, + 3 Lt (d>) (/] f, + (51) () tac6 Cl e d- 2 + ttic / (£) '7G) {{dg} Lt E + 4 + tc ", (f",; to + v gtß d 0I) Lt e 2 + 3 83-; 5 zo / fJ ° CJ tS, S) zzJR Lt g + 23 {9 /) : + + * - {(gCJ (&&) z 9fy f g + 2 + + -2-2 M 3 tif <J // {° / t) {80 {/ {/ {t) e + 3 i33 LI, <J z Lt + (5 /) (9 /) e "'Yc? 9) g (1 '. + 43sffiL34 / 69 / f'.f J £ 1 {~ p + 2 - 4 tSCJ {) 6 + + 3 (f (6c) *.

Table III continued For related t activation of shutdown Time rt transistor ((blocking) of Trans is tor 6 5 ß {9tf) ~ c + - f3s, 13- ~ l3 «eJ fR) 4- 7r ~ r 1 2 --e-5 ~ ßf {) f /) II + - Lt D +; wRs -t- 3 -it5- ~ -34- toDW) 3t. Iu - (t) ££ dtC / (5i) t S ldj ") f & j £ ,, d / a *) t <iS fw S / 9XJ 6 + Fi. ^ -3t {902 [/ t / Ud 2 P »i} * + z-- 3 3 3 {882, 4 tdy 3 r) t, 'e 4 '4 tllfd / J,' e) tAi'J {«) 6 + ir r 1t3 + (j) (lltC / + (; s ,, s {"". ^ J) -,. (? 5) in addition t- 69) {DS VwJ gii tr f 7r i () 3 {8W) et vDfEJ j9, / r / ts Lt it 7; (3>(& 9) t 9 «} t CF? - - -3 - $% - 2 E + 7; /? RP ?, f f9 ° J bCg) 4th C + -, 7g "» - 9 ß c: 9/0 1 'r () Table III continued For related i switching on! Switch off Time r = or transistor (blocking) of transistor Et g 3- i fF + rfla ff) ^ + rr Tm | , {90Y +, r ru +, 2 {{SJ / 4 e -'- T -t: 3i + 3 P + 3 Jr + / 34 z "" y tseR Jr + * () tr jOJ (51) and j () £ 11W + (0 ° 9) e "zd {gfJ £ 's + 44 + 3 S - 3e {/ dj ", 0) (& 5) b", 8 K) 4th cii] tr + A3 tSJ {J8J s + r + S + 9 33 {"t 8§) £ ffld (Bg) r + g 3 (5 / t / K {J / nd / «tzef ts ^ gJ 4th g + rd 3 M {6S} c / £, e, c / 6 & t ') f6tj ,, s, o' (5,) t + 4. plus (<f) two (&) E ++ / i + (1) / 'u + - s, 4 6 4 ~ Y {igJ - J 6N'9 (Q ") I d8 / Table III continued For related t activation of shutdown Time rk, t ransistor} Srpanesrrisento) rvon transistor £ + Art 4 - gf I c E ßr + 1 (g) 4th 0 E / 35 d- ff - 4th E + + g - 3 v '3 cco) 9 e + r ß9 / 3 "ftc)""H 3 stU 2 t - (8 + twoJ {{@tCX fwN) 4th E d- i, 'rt / tDJ awz gJ 4th 6? + 3 (S6 / (cflf) eJ {9f) (C) / t9CJ 4. 2, 7 7i j33 t9 + oreJ fE 3 E, ß3 + '(irn £ W 6 & jyc, ttcv s (89 / lrc c / t / (4- / j - 2 () e, erc / K- ') (c?) (, D (5t) Et Z t - / B9) Cllr / / 8 // lggl e) + 3 (&<f) aad (5) "G teJ g faS} sq- 2 r (Y, X, {ggy K & d) 2 E 4 '2 3 for () 4th Oj (50) (PS) ,.? .-. R / æ; J 9v) ore - 2 7T (04) Further following a key idea of the present invention, the suction throttle (96) in FIG. 28 can of course also be provided with further taps, which are connected to the plus or minus section of the receiving DC voltage system via diodes and thyristors or transistors. As a result, the number of degrees of freedom in the design of the stepped curve uT (z) can be further increased without the individual magnetic components becoming too complicated or being extremely stressed.

The simplest arrangement is that according to FIG. 29, in which the suction throttle according to FIG. 28 only receives two additional taps has, which via two simple diodes (97) and (98) to the plus rail of the receiving DC voltage system are connected. This arrangement according to FIG. 29 allows as 28 the setting of a total of 6 gear ratios u / E Two of which can be freely chosen, one of which can be chosen with restrictions can and one more is set with it, while the remaining two (0 and 1) are fixed anyway. For the creation of a suitable curve shape for the voltage u from the center of the original, now connected to the push-pull transformer (99) Suction throttle to the negative pole of the bridge rectifier one has thus over a total of 8 degrees of freedom (namely e.g. the voltage levels JL2 s Y5 and y3 # 1 y5, which then the voltage levels y1 2 and y4 by virtue of y1 = 1/2 y2 and y4 = y2 + y3 - y2. y3 / y5 are assigned, as well as the five switch-on intervals ß1, ß2, ß3, ß4 and ß5).

If the interchanging of the switching states of the four transistors (88) to (91) not only - as described in Table III - after the end of each quarter of the time interval belonging to the voltage level concerned, but rather starting with switching on this voltage level at equidistant time intervals, the time interval belonging to this voltage level by means of a division by a number z '(z' = 4.n, where n = 1, 2, 3 ...), then with increasing z 'with the acceptance of a higher switching frequency a drastic reduction the induction stress of all three push-pull part transformers contained in FIG or a significant reduction in size can be achieved. For such high switching frequencies The arrangement according to FIG. 29 is recommended (and of course that according to FIG Fig. 28) in a special way, since it has no thyristors, their release times the possible switching frequency would restrict upwards.

Otherwise, the three now contained in the arrangement according to FIG. 29 can be used Push-pull autotransformers, of course, also with additional secondary and primary-side Taps are provided, which with the interposition of thyristors and Diodes or transistors to the plus or minus rail or to the taps of the following push-pull transformer are performed. Shows only as an example 30 shows a circuit of this type, in which, in addition, the supply lines are also connected the centers of the two outer push-pull parallel converters (86) and (87) still have thyristors were inserted to increase the number of degrees of freedom with as little effort as possible to drive high.

It is of course also possible to use FIGS. 28, 29 and 30 described multiple balanced energy converter via AC suction chokes for their part to operate in parallel again. These AC suction throttles can then also be used again be provided with further taps, which via diodes and thyristors or transistors with the plus or minus rail of the receiving DC voltage system are connected.

In each of the push-pull parallel converters described so far, one Rail of the receiving DC voltage system (in the examples described acted For example, it is always the minus rail) via the uncontrolled rectifier (3) alternating with the left and right conductors of the feeding AC voltage system (1) connected.

In certain cases this can have disruptive consequences, e.g. if one of these conductors is the neutral point conductor (Mp) of a three-phase system acts and if at the same time use of the principle of residual current circuit breaker should be made.

Then namely the said minus rail of the receiving DC voltage system during a half cycle of the voltage of the feeding AC voltage system connected to the potential of Mp, which is practically constant with respect to earth, while the other half-oscillation of the voltage of the supplying AC voltage system, on the other hand with the sinusoidally variable potential of an outer conductor with respect to earth.

This can cause significant currents through the capacities of the recipient DC voltage system to earth are caused, which in turn the Can bring residual current circuit breaker to respond.

To describe the remedial measures that can be easily implemented starting from the particularly simple push-pull parallel converter (100) according to FIG. 31, in which only two (primary) transistors and two Secondary diodes and two secondary thyristors are included.

If now the feeding AC voltage system, as shown in Fig. 32, consists of a center conductor (101) and an outer conductor (102), so can a dynamic change in the potential of the receiving DC voltage system (103) to the neutral conductor (Mp) are prevented by two Push-pull parallel converters are used, whereby the example shown above (104) has the same structure as that in FIG. 31 and the positive half-oscillation of the current i leads in the AC supply line, while the example shown below (105) with swapped collector-emitter connections of the transistors as well as swapped The anode-cathode connections of the diodes and thyristors result in the negative half-oscillation of the current i in the alternating current lead.

During the positive Elalb oscillation of the voltage UT and the current The two transistors of the lower push-pull converter (105) are permanent locked and the upper push-pull converter (104) is operated in the manner like this for push-pull parallel converters connected to full bridge rectifiers has already been described several times. Conversely, remain during the negative half-oscillation the voltage uT and the current i the two transistors of the The upper push-pull converter (104) is permanently blocked and the lower copy (105) is controlled in a mirror-inverted manner, as is half a period the voltage of the feeding AC voltage system happened earlier with the upper one.

In this arrangement of FIG. 32, the receiving DC voltage system (103) a total of the voltage 2E. The center conductor. of the feeding AC voltage system acts as a neutral (106), opposite which the plus rail (107) the potential + E and the minus rail (108) has the potential -E.

Because of the existing voltage symmetry to the center conductor this arrangement can be used without difficulty for connection to a three-phase system be tripled. This should also be done later using a simplified version With the help of sketches.

The two primary-side remaining in this arrangement according to FIG. 32 Gl.eichrichterdioden (109) and (110) can without changing the electrical behavior is effected, doubling their number also in the Leads to the (primary-side) switching transistors are laid. Is this carried out, the arrangement according to FIG. 32 a results from FIG. 32.

The disadvantage of the overall arrangements according to Fig. -32 and Fig. 32 a that namely, the two push-pull AC converters are only used half as well as that described earlier can largely be eliminated by using the two push-pull part transformers be summarized. In this way, from the arrangement according to FIG. 32 a those according to FIG. 32b, which differ from the original one shown in FIG Circuit differentiates as follows: - The input bridge rectifier is omitted, - The single push-pull converter has become a bridge push-pull converter.

As the following examples will further illustrate, arises thereby a bridge push-pull parallel converter from the corresponding single push-pull converter basically in the following way: - The push-pull spare transformer remains unchanged, - Transistors arranged on the primary side (electronic one-way switches) are through Anti-parallel connections of transistors provided with series diodes (electronic Two-way switch) replaces, - thyristors arranged on the primary side (switchable electronic one-way switches) are made by antiparallel connections of thyristors (switchable electronic two-way switches, triacs) replaced, - On the secondary side, they become a rail of the receiving DC voltage system leading diodes and thyristors complemented in a mirror image manner by thyristors and diodes which are led to a second rail opposite the neutral has the opposite potential of the first-mentioned rail.

The electronic ones required in such bridge-type balanced converters Two-way switches can of course also be implemented in other ways, for example such that, as shown in Fig. 33, the DC outputs of diode bridges connected via transistors, after which the remaining AC connections the diode bridges as the main power connections of the resulting electrical two-way switch fungicren can whose switching state via the base-emitter path of the contained To affect transistors.

The operation of the arrangement according to the invention when using Bridge push-pull parallel converters will be explained in somewhat more detail in this FIG. 33 by way of example. With this arrangement according to FIG. 33, a sufficiently large dimensioned Inductance of the differential voltage choke (2) as well as a suitable one Choice and assignment of e and E ensures that the current i in the AC feed line to the center of the bridge push-pull par converter (111) is greater than zero as long as the staircase voltage uT is greater than zero and that this current i is less than zero is, as long as the staircase voltage uT is less than zero, then this staircase voltage decreases uT shows the curve sketched in Fig. 34, provided that the two switching transistors (112) and (113) and the four thyristors (114) to (117) synchronous with the voltage uN des feeding AC voltage system according to the following table IV influenced will.

TABLE IV TABLE IV From # = # to r = C + β1 both transistors (112) and (113) are conductive and (as a result) all thyristors are blocked. For related I switch on I switch I ignition of Time 7 = tt t of transistor (blocking) of I thyristor | Transistor £ + / 84 ~ {J fv E, eÆ + (-j '?) Ki) 2 6443) (6>) E ti,? R Ve 2 ~ {{?} ~. 4th ct 133 - lt {dz3) E * "-; r J {v« 3 e + r - iß} kH3) fz / Pa 2 + - fta?} 6/3) (iis) Jr (4/3) 6+ 7 + 4 (3) {ç «3Y C + tf + i / 3 [fii)) {z + 6J E + t d- C C3, 1if) - E + r 4. 9 +, 4-. (443) {+ «J. c + i- + (4/3) E ~ CF -, f +? VR3- # Z z 3J z J ~ 2 ,, E dt {ß> fade) / J e) + net - 76 - The same conditions can thus be achieved with regard to the staircase voltage and the current in the AC feed line as with the single push-pull energy converters discussed earlier. Thus, most of the considerations made about the single push-pull parallel converter basically also apply to the bridge push-pull converter. This applies in particular to the appropriate choice of e and E as well as the appropriate assignment of these two variables to each other, for the control of the transistors and thyristors via a switching logic synchronized with the feeding AC voltage system, for the setting of the voltage E, for influencing the voltage drawn from the AC voltage system Power, for the synchronization of the switching logic with the current i in the AC supply line, for the insertion of shunt capacitors and suction filters in the output circuits, for the insertion of chokes, blocking filters and low-pass filters in the input circuits, for the increase and use of the degrees of freedom in the formation of the Staircase voltage uT, for switching more than two times to the respective voltage levels, for suitable measures for overload protection, for suitable switch-on and switch-off relief networks for the switching transistors, for the introduction of additional primary-side winding taps on the push-pull part crane sformator as well as for the parallel operation of push-pull power converters via suction chokes and the addition of the last-mentioned to push-pull power transformers.

The introduction of additional, primary-side winding taps is explained in somewhat more detail with reference to FIG. 35. The arrangement shown there represents a bridge counterpart to the single push-pull parallel converter arrangement sketched in FIG The secondary part of this circuit has already been described with reference to FIG. The additional primary taps of the push-pull transformer are each with one Thyristor bridge branch (118) and (119) connected, the free thyristor cathode with the collector nd its free thyristor anode with the emitter connection of the relevant Circuit half belonging switching transistor (112) or (113) is connected. the outer primary-side taps of the push-pull autotransformer are in the same Connected to the neutral (120) as in Fig. 35. The control of the transistors and thyristors of this arrangement is carried out analogously to Table IV and Table II.

The parallel operation of bridge push-pull economy converters via suction throttles and the addition of the latter to push-pull part transformers is based on 36 explained in somewhat more detail. The arrangement shown there is a bridge counterpart to the single push-pull parallel converter arrangement sketched in FIG represent. The electronic two-way switches required on the primary side were again in realized in the simplified manner as presented for the first time in FIG. 33 are.

In addition to this simplification on the primary side, there is another one those on the secondary side. 37 shows the arrangement according to FIG 33, the entire primary part of which has been adopted unchanged.

On the secondary side of the bridge push-pull parallel converter, however, were the thyristors (114) to (117) replaced by diodes and instead in the supply lines to the associated secondary winding taps, so-called triac's (bidirectional thyristor triodes) (121) and (122) inserted, whereby the triac (121) is to be ignited each time 33 the thyristors (114) or (116) would have to be triggered. Is accordingly to release the triac (122) when, according to Fig. 33, the thyrisotrene (115) or (117) would be to ignite.

As already explained, all these bridge-type push-pull converters can without difficulty due to the voltage symmetry they give to the center conductor can be tripled for connection to a three-phase network.

An example of this is an arrangement in FIG. 38 sketched, in which three bridge push-pull parallel converters (123), (124) and (125) according to FIG. 33 primarily via one differential voltage choke each to the outer conductors R, S and T of one feeding three-phase voltage system and secondary with one and the same absorbing DC voltage system with the plus rail (126), the minus rail (127) and the neutrals (128) are connected. In this three-phase arrangement, the Center conductor Mp of the feeding three-phase voltage system (129) not necessarily be connected to the neutral (128) of the receiving DC voltage system. Rather, it can even be very advantageous not to establish such a connection, because then no harmonic currents flow in all three AC supply lines, whose frequency is equal to three times the network frequency or equal to an integer Is multiples of this. As a result, when designing the staircase curves UTR, UTS and UTT the harmonics contained therein with the ordinal numbers 9 = 3 (2p-1), p = 1.2 ... co are disregarded as they do not have any disturbing currents in the AC power lines can cause. About the available Degrees of freedom can thus the remaining harmonics with the ordinal numbers 2 5 (s = 1,2. .00, s 3 (2p-1), p = 1,2 .. 00) can be kept even smaller (since on the aforementioned just no longer be taken into consideration got to).

There is no need for further explanation that in all herewith presented arrangements, especially in the described push-pull parallel converters as well as bridge push-pull par converters - the semiconductor diodes contained by others uncontrolled electrical one-way valves, - the contained thyristors by others switchable electrical one-way valves, - the included triacs by other switchable electric two-way valves and - the transistors contained by other electric One-way switch (e.g. switch-off thyristor tetrodes or erasable thyristor combinations) can be replaced without thereby fundamentally affecting their function being affected.

Exemplary for the replacement of transistors with erasable thyristor combinations let us start from the particularly simple push-pull parallel converter (100) according to Fig. 31, in which only two (primary) transistors as well as two secondary diodes and two secondary thyristors are included.

39 shows the arrangement according to FIG. 31 after the two transistors have each been replaced by an erasable thyristor combination (130) and (131).

The latter consist of a charging throttle (132) each, one main thyristor (133), a quenching capacitor (134), a quenching thyristor (135), a recirculation throttle (136), a recycle diode (137), a reversing throttle (138) and a reversing thyristor (139). Such a replacement of the transistors by such erasable thyristor combinations, as they are known in great variety, is particularly recommended when using the device according to the invention in the area of high performance, e.g. in the preparation of energy for the drive motors electric locomotives.

Finally, referring to FIG. 40, a so-called battery supply device is briefly shown are described in which the device according to the invention in very advantageous Way can be used.

In the exemplary arrangement according to FIG. 40, there is this battery feed device one after the other from the feeding AC voltage network (140), the differential voltage choke (141), the uncontrolled input rectifier in a bridge circuit (142), the push-pull converter with stepped variable voltage transmission (143), a shunt capacitor with a Suction filter connected in parallel for twice the frequency of the feeding AC voltage network (144) and an isolated, direct current converter with controllable ends Gear ratio (145) according to German patent application P 2710938.2 (there Fig. 9). The electrical energy taken from the feeding AC voltage network (140) So the differential voltage choke, the input rectifier, happens one after the other in bridge circuit, the push-pull parallel converter and the forward converter and flows from the latter to the storage battery to be charged (146). The control takes place here of the entire system via the "control unit push-pull parallel converter" (147), the "control unit Flow converter "(148) and the charging current regulator (149). If from a certain Operating state, the actual value 1 is the current with which the battery (146) is charged, is to be increased, then the setpoint Isoll of this current is greater to prescribe. Then the charging current regulator (149) is the transmission ratio ü = Increase UB / E of the direct current flow converter (145). As a result, the Output voltage E of the push-pull converter (143) drops. The control unit (147) the push-pull parallel converter is then (by way of a control or regulation) for it ensure that the angle g corresponds to the new value of E in the manner described several times tracked, is enlarged in the present case.

This has the consequence that the feeding AC voltage network (140) a larger power is taken and this is fed to the battery that is fed. This increases the actual value of the battery's charging current on the now prescribed target value. As indicated in FIG. 40, this rule can for the setpoint of the battery charging current e.g. via a function generator the battery voltage UB can be derived.

Claims (37)

Claims: device without loss of principle due to the principle of extraction of line-frequency, largely sinusoidal current from AC networks and for transferring the extracted electrical energy into galvanically connected DC voltage systems characterized in that between the feeding AC voltage network with the Voltage u, and the receiving DC voltage system or DC voltage intermediate system with the voltage E at least one electrical choke, the so-called differential voltage choke, a rectifier in a bridge circuit and a so-called single push-pull converter is switched with stepped variable voltage translation and that this single push-pull converter contains a so-called push-pull part transformer, which consists of a closed magnetic core and a continuous winding applied to it, which is symmetrical about its center and a center tap used on the primary side, two external taps used on the primary side and an even number on the secondary side has external taps used and that one of the two input-side DC connections of the single push-pull parallel converter through the center tap of the push-pull autotransformer is formed and the other the both input-side DC connections of the single push-pull converter formed by two interconnected main current connections of two transistors with these transistors symmetrical to the center of the push-pull part transformer are arranged and their respective remaining main power connections to the primary side external taps of the push-pull transformer used are connected and that one of the two output-side direct current connections of the single push-pull converter is formed by those of its input-side DC connections, which does not coincide with the center tap of the push-pull autotransformer, and the other of the two DC connections on the output side of the single push-pull converter is formed by two interconnected main power connections of two diodes, these diodes arranged symmetrically to the center of the push-pull power transformer are and their remaining main power connections to the two inner secondary side used external taps of the push-pull power transformer are connected and that the remaining external taps of the push-pull autotransformer are below Interconnection of thyristors to the direct current connection on the output side of the single push-pull parallel converter are performed, which by the two interconnected main current connections of the diodes is formed and that all of the external taps of the push-pull transformer used on the secondary side connected electrical valves are uniformly connected so that a Electric current flow either only from the external taps of the push-pull transformer away or to these external taps is possible, and that the two output-side DC connections of the single push-pull parallel converter with one rail each of the receiving DC voltage system or DC voltage intermediate system are, and that the two input-side DC connections of the single-push-pull converter with one of the two DC connections of the rectifier in each case in a bridge circuit are connected and that the two AC connections of the rectifier in a bridge circuit with the interposition of at least one throttle with the two rails of the feeding AC voltage network are connected. 2. Device according to claim 1, characterized in that the when described single push-pull parallel converter existing possibility, its conversion ratio from input to output voltage then, if for center tapping its push-pull part transformer towards or away from this a current of such Sign flows that it is also via the diodes arranged on the secondary side can continue via the control of the included transistors and thyristors to be able to change in several stages, is used to move between the both input-side DC connections of the single push-pull converter sets a voltage u in the form of an ascending and descending staircase, which in a first time interval of a quarter of the period of the feeding AC voltage system from the value zero with steps leading to higher values continuously to a maximum value increases and then in a second time interval of a further quarter the period of the feeding AC voltage system from this maximum value drops back to the value zero via steps leading to lower values continuously, whereby the ascending and descending part of the stair curve are mirror images of each other run and then in a third and fourth time interval of the processes for a quarter of the period of the feeding AC voltage system of the first and second time interval and in the electrically settled Continue in this way and that the control the transistors and thyristors contained in the single push-pull converter described is made by a switching logic, which is connected to the feeding AC voltage network is synchronized directly or indirectly and that the time shift of the double mains frequency staircase voltage u between the input-side direct current connections of the single push-pull economy converter compared to the also in double network frequency Result of occurring zero crossings of the voltage u, of the feeding AC voltage network and the voltage, E of the receiving DC voltage or DC voltage intermediate system be set so that on the one hand the feeding AC voltage network the desired electrical power is withdrawn and on the other hand the current is in the AC supply line to the rectifier in the bridge circuit always then and only then goes through zero, that is from positive values to negative and vice versa changes over when the voltage u between the input side DC connections of the single push-pull converter has the value zero. 3. Device according to claim 2, characterized in that over the on the shape of the double network frequency staircase voltage u between the input ports DC connections of the single push-pull parallel converter influencing variables, namely the locations of the Taps of the continuous winding of the push-pull autotransformer and temporal The intervals between the switching operations from one stage to the next are arranged in such a way that that the waveform of the current iv in the AC line from the feeding AC voltage network as closely as possible approximates the sinusoidal shape in such a way that the in this Electricity contained, the supplying electricity company or in parallel connected or otherwise influenced consumers disturbing harmonic currents with the smallest possible differential voltage choke limited to still permissible values can be. 4. Device according to claim 2 or 3, characterized in that the magnetic flux, which in the case of the described, is a mirror image of its center symmetrical single-push-pull parallel converter when switching on a certain switching state builds up, is then reduced back to the previous state in that for the same period of time for which said switching state is established was, then the mirror-inverted symmetrical switching state of the single push-pull converter manufactured is that the single counter-clock converter is in the so-called electrical push-pull is operated. 5. Device according to one of claims 2 to 4, characterized in that that the voltage value zero of the double line frequency staircase voltage u between the two input-side DC connections of the single push-pull converter is set in that both transistors are placed in the conductive state and that the lowest level of the staircase voltage u is set by that only one transistor is put into the conductive state and within the opposite Half of the circuit, the thyristor located furthest outside is ignited and that the step following the bottom step of the staircase tension upwards is set in that only one transistor is put into the conductive state and within the opposite half of the circuit the second outermost thyristor is ignited and that in a corresponding manner the subsequent upward stages the staircase voltage and that the second highest step of the staircase voltage through this is set so that only one transistor is put into the conductive state, and no thyristor is ignited and that the highest step of the staircase voltage is thereby is set so that no more transistor is put into the conductive state and no more thyristor is ignited. 6. Device according to claim 5, characterized in that in that Time interval during which a certain step of the staircase voltage u is set is, the switching state of the single push-pull economy converter more than once is a mirror image is symmetrically exchanged between one and the other circuit half. 7. Device according to one of claims 1 to 6, characterized in that that the control of the transistors and thyristors contained there in the electrical steady state with twice the frequency of the feeding AC voltage network is repeated periodically. 8. Device according to one of claims 2 to 7, characterized in that that the time shift of the double line frequency Stair tension u between the load ~ w ~ 7 input-side DC connections of the single push-pull converter compared to the zero crossings which also occur in a double line frequency sequence the voltage u, v of the feeding AC voltage network thereby to the desired Value is set so that the temporal position of the zero crossings of the current i, in the AC feed line to the rectifier in a bridge circuit relative to the voltage u between the two input-side DC connections of the single push-pull converter detected and by a uniform relocation of the transistor switching as well as the Thyristor ignition times relative to the voltage u ~ of the feeding AC voltage network is set or regulated so that the zero crossings of the current in the AC supply line to the rectifier in a bridge circuit roughly in the middle of that Time intervals come to lie in which the voltage u between the two input-side DC connections of the single push-pull parallel converter assumes the value zero. 9. Device according to one of claims 2 to 7, characterized in that that the time shift of the double line frequency staircase voltage u between the two Input DC connections of the Eitçavch push-pull converter compared to the zero crossings which also occur in a double line frequency sequence the voltage us of the feeding AC voltage network thereby to the desired Value is set that the described switching logic, which the control of the transistors and thyristors, not with the voltage u ~ of the feeding AC voltage network but directly with the current i, in the AC supply line is synchronized to the rectifier in the bridge circuit. 10. Device according to one of claims 1 to 9, characterized in that that the differential voltage choke is not in the AC line to the bridge rectifier but in one of the supply lines to the two input-side DC connections of the single push-pull parallel converter is inserted and the rectifier in a bridge circuit to ensure the fact that he is as current-controlled and not as voltage-controlled Switch works, is designed as a half or fully controlled bridge circuit, their control is carried out so that the current i, in their AC supply line reverses its direction only when it has previously become zero, in such a way that the non-live branch only then is ignited when the Current in the current stromPhHrJeF has assumed the value zero. 11. Device according to one of claims 1 to 10, characterized in that that within the switch-on interval of a step of the staircase voltage u between the two input-side DC connections of the single push-pull converter not only the corresponding level value but also the previous and the subsequent step value is set such that within the first half of the time interval # dt belonging to the voltage level concerned at an or several places during the period g (g and t are positive, even Numbers and g <# z 2) the previous step value is set and that within the second half of the time interval belonging to the voltage level in question dt at one or more points during the time periods g # t / z the following Step value is set. 12. Device according to one of claims 1 to 11, characterized in that that the push-pull part transformer contained there used not only two primary side Has external taps, but larger with an even number two such external taps used on the primary side is provided and that the with it additional external taps used on the primary side in the middle of the circuit mirror image symmetrically to the main power connection of one transistor each are performed whose remaining main power connection is of the same type as those main power connections of the already existing transistors, which, with each other connected, one of the two input-side DC connections of the single push-pull converter form and that these remaining main power connections of the thus additionally introduced Transistors also with those main power connections of the already existing transistors, which are already connected to each other, to be merged and that in all connecting lines from the external taps used on the primary side of the push-pull part transformer to the transistors, with the exception of the two inner ones, Diodes are inserted, which are connected to the external taps of the push-pull transformer are connected with the same kind of their main current electrodes with which the connected to the two inner external taps used on the secondary side Diodes are connected there and that all possible transmission ratios -from the input voltage to the output voltage of the resulting '§Single push-pull economy converter with additional primary taps of the push-pull part transformer "for training the staircase voltage u between the two input-side DC connections of the single push-pull parallel converter are used and that the lowest level is zero this staircase voltage u is set in that it is a mirror image of the middle of the circuit symmetrically placed at least two transistors in the conductive state and that the highest level E of this staircase voltage u is thereby set will; that all transistors are put into the blocking state and that another part of the voltage levels is set in that in one half of the circuit put one of the transistors contained there in the conductive state and that the remaining part of the voltage levels is set by that in one half of the circuit one of the transistors contained there in the conductive State shifted and in the other half of the circuit one of the there to the secondary side used external taps of the push-pull part transformer connected thyristors ignited will. 13. Device according to one of claims 1 to 11, characterized in that that the push-pull part transformer contained there used not only two primary side Has external taps, but with an even number greater than two such on the primary side external taps used is provided and that the additional existing ones External taps used on the primary side in mirror image to the middle of the circuit symmetrically to that main power connection of the relevant circuit half belonging transistor are performed, which is already used with a primary side External tapping is connected and that in the two outermost ones Connecting lines from the external taps of the push-pull transformer used on the primary side to the transistors diodes are inserted, which are connected to the external taps of the push-pull transformer are connected to the same type of main power connector as the connected to the two inner external taps used on the secondary side Diodes are connected there and that in the other connecting lines from the primary side used external taps of the push-pull part transformer to the transistors Thyristors are inserted, which are connected to the external taps of the push-pull transformer are connected to the same type of main power connector as the there are connected thyristors to the external taps used on the secondary side are connected and that all possible ratios of input voltage to the output voltage of the resulting "single push-pull parallel converter with additional Primary taps "of the push-pull autotransformer to develop the staircase voltage u between the two input-side direct current connections of the single push-pull converter are used and that the lowest level zero of this staircase voltage u thereby is set so that both transistors are placed in the conductive state and possibly in a mirror-inverted manner to the circuit center even number of thyristors used on the primary side is ignited and that the highest level E of this staircase voltage u is set in such a way that both transistors be placed in the blocking state and that a further voltage level thereby is set that one of the two transistors in the conductive State is offset and that a further part of the voltage levels is thereby set is that one of the two transistors is put into the conductive state and one of the thyristors leading to this transistor is triggered and that another Part of the voltage levels is set in that one of the two transistors is put into the conductive state and in the opposite half of the circuit one of the external taps of the push-pull spartrans used there on the secondary side foriiators connected thyristors is ignited and that the remaining part the voltage levels is set in that one of the two transistors is put into the conductive state and one of the leading to this transistor Thyristors is ignited and in the opposite half of the circuit one of the there to the external taps of the push-pull transformer used on the secondary side connected thyristors is triggered. 14. Device according to claim 12 or 13, characterized in that they of the described possibility that between the two input-side DC connections of the single push-pull parallel converter is one step-shaped voltage u can be formed and that this over switch-on times of the transistors and ignition times of the thyristors with the feeding AC voltage network can be synchronized, makes use in the same or an analogous way as this for arrangements that use a single push-pull parallel converter without additional primary taps contained on the push-pull autotransformer, with claims 2 to 11 is set forth. 15. Device according to claim 12, 13 or 14, characterized in that that to form the staircase voltage u between the two input-side direct current connections of the single-push-pull economy converter with regard to the stress on the transistors and / or thyristors or the push-pull part transformer not all possible Step-up ratios of input voltage to output voltage of the single push-pull converter can be used with additional primary taps of the push-pull autotransformer. 16. The arrangement from one of the devices according to claims 1 to 15 emerging, characterized in that that the one contained there Single push-pull parallel converter is replaced by a circuit that consists of two such There is a single push-pull economy converter, which has an alternating current suction throttle operated in parallel. 17. Device according to claim 16, characterized in that the Center taps of the two push-pull part transformers contained there, respectively are connected to one of the two external connections of the AC suction throttle and the center tap of the alternating current suction throttle on one of the two c-input sides DC connections of the resulting suction throttle single push-pull economy converter forms and that those input-side DC connections of the two contained there Single push-pull parallel converters, which are not through the center taps of their push-pull part transformers are formed, are brought together to a node, the second Input-side direct current connection of the resulting suction throttle single push-pull economy converter forms. 18. Device according to one of claims 1 to 15, characterized in that that the transistors contained there in turn through single push-pull AC converter be replaced, whereby the two input-side DC connections of these, the originally contained transistors replacing single-push-pull parallel converters take the place of the two main power connections of the replaced transistors and that of the two output-side DC connections of the replacing Single push-pull parallel converter, which is achieved by two main power connections connected to one another two diodes is formed, with that output-side DC connection of the resulting "single push-pull economy converter with wired Saugdrosscl" connected st, to which no transistors are connected. 19. The device according to claim 18, characterized in that in the Supply lines to the center taps of the push-pull part transformers contained there Thyristors are inserted, which are connected to the center tap of the push-pull transformer is connected to that of its two main current electrodes, which are not at the same time The variety belongs like the other external connections used on the secondary side thyristor main current electrodes connected to the push-pull part transformer in question. 20. Device according to claim 18 or 19, characterized in that that the transistors contained there in turn by single push-pull converter be replaced, whereby the two input-side DC connections of these, the transistors contained there replacing single-push-pull parallel converters to the Step in place of the two main circuit connections of the replaced transistors and each that of the two output-side DC connections of the replacing single push-pull converter, which is formed by two interconnected main power connections of diodes is, with that output-side DC connection of the resulting "single push-pull economy converter with wired multiple suction throttles "connected to which no transistors are connected. 21. Establishment without losses due to the principle of operation for the extraction of network-frequent, largely sinusoidal current from alternating voltage networks and for the transfer of the withdrawn electrical energy in galvanically connected three-wire DC voltage systems, characterized in that between the feeding AC voltage network with the Voltage u ~ and the absorbing DC voltage system with the voltages + E and -E at least one electrical choke opposite the neutral, the so-called differential voltage choke, and a so-called bridge push-pull converter is connected with a step-variable voltage ratio and that this bridge push-pull converter from the single push-pull converter described in claims 1, 12 to 15 and 17 to 20 it can be seen from the fact that the respective push-pull part transformers remain unchanged remain, the transistors contained there by anti-parallel connections of with Transistors with series diodes (i.e. through so-called electronic two-way switches) are replaced, the there on the primary side used external taps of the push-pull transformer There are no connected diodes, the external taps used there on the primary side thyristors connected to the push-pull part transformers by anti-parallel connections by thyristors or by triacs (i.e. by so-called switchable electronic Two-way switch) are replaced, the output side there to a rail of the receiving DC voltage or DC voltage intermediate system moving diodes and thyristors be supplemented in a mirror-inverted manner to the neutral by thyristors and diodes which are led to a second rail opposite the neutral the has opposite the same potential of the first-mentioned rail, while the both input-side DC connections of the bridge push-pull converter remain the same as with the respective single-push-pull converter from which the bridge push-pull parallel converter emerges. 22. Device according to claim 21, characterized in that the with the bridge push-pull parallel converter described, there is a possibility of its transformation ratios from its input voltage to its output voltages via the control of the contained transistors, thyristors and possibly triacs in several stages to be able to change, is used that between the two input-side DC connections of the bridge push-pull converter a voltage u in the Sets the shape of an ascending and descending staircase, which in a first time interval of a quarter of the period of the feeding AC voltage system of the value Zero with steps leading to higher values continuously to a maximum value increases, then in a second time interval of a further quarter the period of the feeding AC voltage system from this maximum value from progressively to smaller ones Upgrade leading levels again the value zero decreases (whereby the ascending and descending part of the staircase curve run mirror images of each other), then in a third time interval of a further quarter of the period of the feeding AC voltage system from the value zero to a minimum value via steps leading to smaller values continuously falls and then, in a fourth time interval of a further quarter the period of the feeding AC voltage system back to the value zero increases (with the positive and the negative part of the staircase curve being point-symmetrical run to each other) and which are then in the electrically steady state continues in the manner described and that the control of the described in Bridge push-pull parallel converters contained transistors, thyristors and possibly Triacs is made by a switching logic, which with the feeding AC voltage network is synchronized directly or indirectly and that the time shift of the double mains frequency staircase voltage u between the input-side direct current connections of the bridge push-pull economy converter compared to the voltage uw of the feeding AC voltage network and the voltages + E and -E of the receiving DC voltage and DC voltage intermediate system so be set that on the one hand the feeding AC voltage network the desired electrical power is drawn and, on the other hand, the current is in the AC supply line to the rectifier in the bridge circuit always goes through zero if and only if the voltage u between the two input-side direct current connections of the bridge push-pull converter has the value zero. 23. Device according to claim 22, characterized in that over the locations of the taps of the continuous winding of the push-pull autotransformer and the time intervals between the switching processes from one to the next stage accordingly Claim 3 is ordered. 24. Device according to claim 22 or 23, characterized in that that it is operated according to claim 4. 25. Device according to one of claims 22 to 24, characterized in that that it is operated according to claim 5, the corresponding values being reversed Polarity of the double mains frequency staircase voltage u between the both input-side DC connections of the bridge push-pull converter be set in that the with claim 21 in a mirror image of the neutral Manner added transistors and thyristors switched on in an equivalent manner or be ignited. 26. Device according to claim 25, characterized in that it according to claim 6 is operated. 27. Device according to one of claims 21 to 26, characterized in that that the control of the transistors and thyristors contained there in the electrical steady state with twice the frequency of the feeding AC voltage network is repeated periodically. 28. Device according to one of claims 22 to 27, characterized in that that the time shift of the double line frequency staircase voltage u between the two input-side DC connections of the bridge push-pull converter compared to the voltage u ~ of the feeding AC voltage network thereby on the desired value is set that the timing of the zero crossings of the Stromes iN in the AC supply line from the supplying AC voltage network relative to the voltage u between the two input-side direct current connections of the bridge push-pull parallel converter detected and by a uniform shift the transistor switching and the thyristor ignition times are set or regulated in this way is that the zero crossings of the current in the AC feed line approximately in the In the middle of those time intervals come to lie in which the voltage u between the two input-side DC connections of the bridge push-pull converter takes the value zero. 29. Device according to one of claims 22 to 27, characterized in that that the time shift of the double mains frequency staircase voltage u compared to the voltage u, v of the feeding AC voltage network thereby to the desired Value is set that the described switching logic, which the control of the transistors and thyristors, with the current iN in the AC supply line is synchronized to the bridge push-pull converter. 30. Device according to one of claims 21 to 29, characterized in that that according to claim 11 switched back and forth between different voltage levels will. 31. Arrangement from one of the devices according to claims 21 to 30 resulting, characterized in that the bridge-type push-pull converter contained there is replaced by a circuit that consists of two such bridge push-pull parallel converters which are operated in parallel via an alternating current suction throttle. 32. Device according to one of claims 21 to 31, characterized in that that the anti-parallel circuits contained there are provided with series diodes Transistors are replaced by bridge circuits made of diodes, their AC connections as a replacement for the external connections of the replaced anti-parallel circuits of with Series diodes provided transistors are used and their direct current connections via Transistors are connected together. 33. Device according to one of claims 21 to 31, characterized in that that the anti-parallel circuits contained therein are provided with scriend diodes Transistors through Bridge circuits made of diodes are replaced, their alternating current connections as a replacement for the external connections of the replaced anti-parallel circuits of transistors provided with series diodes and their DC connections are connected to each other via transistors and that the ones contained there are connected to the primary side used external taps of the counter-clocking transformer connected anti-parallel circuits of thyristors or triacs are replaced by arrangements of two thyristors, a thyristor with its anode on said external tap and with its The cathode is connected to the cathode collecting point of the bridge circuit made of diodes, while the other thyristor has its cathode on the named external tap and connected with its anode to the anode collecting point of the bridge circuit made of diodes is. 34. Combined device with no losses due to the principle of extraction of line-frequency, largely sinusoidal current from three-phase systems and for Transfer of the extracted electrical energy into galvanically connected three-wire DC voltage systems, arising from the devices according to claims 21 to 33, characterized in that that three identical bridge push-pull parallel converters in a symmetrical manner, each with one of their DC connections on the input side each via a differential voltage choke the three outer conductors of a feeding three-phase voltage network are connected and that the remaining input-side DC connections of the bridge push-pull converter are merged to a point, which is with the neutral of the receiving Three-wire DC voltage system is connected and that the bridge push-pull converter with their output-sidec: v DC connections in a uniform manner with the External conductors of the receiving three-wire DC voltage system are connected. 35. Device according to claim 34, characterized in that the Neutral of the receiving three-wire DC voltage system with the Mp conductor of the feeding three-phase voltage network is connected. 36. Combined device with no losses due to the principle of extraction of line-frequency, largely sinusoidal current from three-phase systems and for Upper guide of the removed electrical Energy in galvanic connected three-wire DC voltage systems, from the devices according to the claims 21 to 33, characterized in that three identical bridge push-pull parallel converters in a symmetrical manner with their two input-side direct current connections Via interposed differential voltage chokes to the three outer conductors of one feeding three-phase voltage network are connected and that the bridge push-pull converter with their output-side DC connections in a uniform manner External conductors of the receiving three-conductor equilibrium voltage system are connected. 37. Device according to one of claims 1 to 36, characterized in that that the semiconductor diodes contained there by other uncontrolled electrical One-way valves are replaced and / or that the thyristors contained there by others Switchable electrical one-way valves are replaced and / or that the contained therein Triacs (three-electrode alternating current switches) by other switchable electrical Two-way valves are replaced and / or that the included transistors by other electrical one-way switches (e.g. switch-off thyristor tetrodes or erasable Thyristor combinations) are replaced.