RU1804687C - Device for summing currents of electrodes in current collection zone of sectionalized magnetohydrodynamic generator - Google Patents

Abstract

Use in systems of summing currents of electrodes and loading MHD, 1 generator. SUMMARY OF THE INVENTION: A device for summing currents of electrodes comprises thyristor bridges (4) consisting of thyristors (5,6). The circuits of the first diagonals of thyristor bridges include an electrode (1), a direct current switch (11), a smoothing reactor (10), and an electric energy receiver (8). The second diagonals of the thyristor bridges include switching capacitors (15), two-winding communication transformers (16), alternating current transformers (17), C of the control unit (18) to the switching coils (12) of the DC switches, the signals are supplied with the corresponding AC transformers 3 ill. ..

Description

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The invention relates to magnetohydrodynamic technology, in particular to a system for summing electrode currents and loading MHD, and can be used in industrial MHD installations. 5

The purpose of the invention is to increase the reliability of the device for summing electrode currents in the current collection zone.

In FIG. 1 shows a device for summing the currents of six electrodes; FIGS. 2-10 an equivalent circuit of two pairs of thyristor bridges; Fig. 3 is a schematic diagram realizing the operation of the automatic block and / -, V; -.// .:: -;.: ;; ..; ; : A summing device is connected to the electrodes 1 of the anode group of channel 2 of the CHDG

Property 3, Bridges 4 of the summing device: consist of thyristors 5 and b. Points 7, combining the cathodes of thyristors 5 and 6 in bridges 4, are the first points of the first diagonal; - - the bridges 4 are connected to the receiver / 20 of electric energy 8. Point 9. unite-: Future anodes of thyristors $ and b in bridges 4, V are the second points of the first diagonal -;

 whether 4 l bridges are connected to the electrodes 1 .-,:; through chains consisting of; afterbirth, 25 telnr included smoothing: pea who ;; Ditch 10 and DC circuit breakers 11 :; ; 6 switching coils 12, /:;: d :; & - H :: Points 13.14 combine the anodes with cat-g; thyristor days 5, 6 in bridges 4 and are 30 points of the second diagonal of bridges 4. In the second: second diagonals of bridges 4, chains are included, 1 consisting of series connected; switching capacitors 15, windings of communication transformers 1 b and transformers 35 AC 17. To the unit of the automation 18 are connected on the one hand the outputs of the transformer 16, and on the other ctOfliO, coil-winding 12 switches 11.; ; / - The electrodes 19 of the cathode group of the channel 2 40 through EE summing device .20, vyplt. analogous to a summing device 3, connected to an electric receiver

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At a signal from the Btixoiia of the automation unit 18, the switches 11 are turned on;

 There are pairs of electrodes of channel 1 of the MHD generator 2 to pairs of thyristor bridges 4, 50 connected by a double-circuit communication transformer16. Thyristor mo-v: sv4 work in dual mode. Thyristors 5 are open and conduct current in the first half-cycle, and thyristors 6 are open and conduct current in the second half-55th period. In the first half-cycle, the current of the pair of electrodes 1 flows through switches 11, smoothing reactors 10, thyristors 5, current transformers 17, winding trance-.

communication formors 16, switching capacitors 15, charging them, an electric energy receiver 8, a similar summing device 20, and a pair of electrodes 19.

In the second half-cycle of thyristor bridges 4, the current of the pair of electrodes 1 flows through switches 11, smoothing reactors 10, thyristors 6, switching capacitors 15, recharging their windings of communication transformers 16, AC transformer 17, electric energy receiver 8, similar device 20 and a pair of electrodes

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If the windings of the communication transformers 16 are turned on and on, then the currents are distributed uniformly across the pair of electrodes. In the event of a failure in the current switching, for example, in one of the thyristor bridges 4 under consideration at the output of the corresponding current transformers 17, the signal becomes zero and, upon command from the automation unit 18, the circuit switches off the pair of thyristor bridges where 11 occurred accidents. In this case, the system does not collapse, and the law of distribution of the current rio to the current-collecting electrodes in the zone is not violated.

: All of the above allows us to make an unambiguous conclusion about what is offered by me: the summation device is more: reliable in operation than the prototype .; : ;; iv The system under consideration, in addition to high reliability, also has. the possibility of realizing from a number of certain concoctions in the distribution of current over the electrodes of the current; removable grain, which can be carried out not only with the aid of the variation of Ctr; but also by changing the values of the switching capacitors at constant Ktr. The latter circumstance can be very convenient when implementing the trapezoidal laws of current distribution over the electrodes of the current collector zone. Consider this with a specific example. Figure 2 shows an equivalent circuit to. one of the half-cycles of the operation of two pairs of thyristra x bridges connected by means of communication transformers. The windings of the communication transformers are included in the opposite direction. The transformation ratio is 1.

. -. . ..,: - /. - -. Let the value of the switching capacitors included in the diagonal-thyristor bridges, at the input of which the voltage 11e2 tb-i, be applied. It is less than the value of the switching capacitors in the thyristor bridges, at the input of which the voltage Usi acts. From the equivalent circuit it can be seen that some conclusions of the switching capacitors are rigidly interconnected and connected to the electric energy receiver, and the other conclusions of the capacitors can also be considered 5 combined, since their potentials are close to each other. Equality of potentials is ensured by means of communication transformers, compensating for the variability of the interelectrode values 10

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Thus, we can assume that the switching capacitors in this circuit are connected in parallel and the voltages on them, regardless of their value, should be the same. With the same gender - -; on the thyristor operation of bridges; v; circuits x, where the values of the switching capacitors are less, and less 1 leak; (10 currents.:;: L ;;;;:., 20 /: d ;;;: Therefore, with a proportional у- - decrease in the values of commuting.con-vD of the densifier with distance from that-, the main zone will be realized Г ; trapezoidal distribution law

 by electrodes of the current-collecting zone. ; D -

: -l Fig. 3 shows one of the VRMOS :: :: schemes that implement the operation of the auto-: x block; matiky. On the diagram; the chains shown; J; allow turning on and off a pair of 30 DC circuit breakers (Ba and B2); For V :; the remaining pairs of circuit breakers are under construction; ;: similar to bbzrmU Consider the operation of the K circuit, pre-presented in Fig.3; WITH

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The transistor tin is tripped; f le Rz, closing its own (“contacts are switched on in the circuit; ECH whose relay is PL At the output of the comparator K:;;

/ there is a low signal, and TraI--. resistor T2 is off. When you press the button 40 On. off Intermediate relay PI is activated; and is held by its contact; enabled state. To the coils in the case of Paradise Р 2, the circuit breaker is applied to voltage and the circuit breakers are switched on, the block contacts of which are closed:;

; cabins in the switching circuit of relay P4. ; On J; the outputs of transformers of alternating TB- / kA voltage is formed, proportionally; the current flowing through the 50 primary winding of the transformers. This: D: the voltage is rectified and applied to. comparator input, where compared to Unop.

When the input signals are equal, the comparator does not receive a high level signal 55. The transistor is turned on; T, the relay RA activates, closing its con-; the clocks in the base circuit of the transistor TL, connecting it to the output of the comparator, closes. RA contact parallel to transistor 2.

In the event of a switching failure in any thyristor bridge, the signal supplied to the input of the comparator becomes equal to zero, a low-level signal appears at the output of the comparator, by which the transistors Tc and T2 are turned off. Relay P3 is de-energized, opening its contacts in the switching circuit of relay Pi. Relay Pi switches off, the voltage is removed from the switching coils of switches Ba and B 2. The switches disconnect, opening their block contacts in the switching circuit of relay P, the relay disappears. The contacts are opened in the base circuit of the transistor Ti and parallel to the transistor. The transistor turns on, the relay reacts; it closes its contacts in turn on the Pi relay. Automation circuit ready for. KEYWORDS

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, About r m at l; and and a goiter of a shadow; l v v; The summation device trkrv elbk - trodbv in the current-collecting area of the seysyrnirirovannogo magnetohydrodynamicheskyrgr; - generator containing thyristor., You, the first points of the first diagonals of which; rykh are united by themselves and connected.;. to the electric energy receiver, and the second points of the first diagonals are connected X0 to the corresponding electrodes of the MHD generator: a torus, a switching capacitor and double-winding transformers, communications; included in the second diagonals of thyristor; bridge bridges, with the exception of the fact that; ; : in order to increase the reliability of operation, the device is additionally equipped with smoothing; ./ reactors ,; dc circuit breakers -1 with switching coils; thyristor unit, and thyristor 1: bridges connected to the electrodes located symmetrically relative to the center of the current collection zone, in pairs connected by double-winding communication transformers, in which each winding is connected last; with a switching capacitor and AC transformers into the second diagonal of the corresponding thyristor bridge, while the second points of the first diagonal of the thyristor bridges are connected to: the corresponding electrodes of the IIGD generator through chains, each of which consists of a smoothing reactor connected in series and you - -d key has a built-in power supply, the power-on coil of which is connected to the corresponding: output of the automation unit, and the inputs of the automation unit are connected to the corresponding transform torams of Gothenburg. ; -; v ;;; : - .- ::; -. . . .-;, -, ...,,

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