FR2578135A1 - THERMO-INDUCTIVE GENERATOR FOR THE PRODUCTION OF HOT FLUID - Google Patents

Abstract

1. A thermoinductive generator for producing a hot fluid, the generator being of the short circuited transformer type comprising a magnetic circuit (1), a primary winding (2) fed with electrical current, and a tubular secondary winding (4) which is electrically short circuited and through which a fluid to be heated flows, the generator being characterized in that said tubular secondary winding comprises, for each phase, a plurality _n of elementary tube circuits (5, 6, 7, 8) which are hydraulically connected (10 to 16), said elementary tube circuits including electrical coupling means (18 to 29), and in that the various elementary circuits are put electrically into service by thyristors (30 to 33) controlled by electronic means.

Description

_- 1 -

  The present invention relates to a thermoinductive generator for the production of hot fluid.

the production of hot fluid.

  British Patent No. 2 105 159A discloses a thermoinductive generator of the transformer type comprising a magnetic circuit,

  a primary winding, supplied with electric current and a winding

  tubular secondary flow traversed by a fluid to be heated, said

  tubular secondary winding being electrically short-circuited

cooked.

  In this document, mention is made of a thyris-

  tors, but the solution presented implies - that the regulation is done at the primary of the transformer because of the complete short-circuiting of the turn of the secondary heating coil, - that the primary voltage is weak and compatible with ee that can support the thyristors, hence a limitation of the power of the devices, - to regulate by variation of the phase angle if one wants a continuous regulation. - from zero to the maximum power without having peaks of intensity when switching on. This solution gives a bad cosine f in the zone of low power called o bad performance. Indeed, the cosine f is all the better than the power

is strong.

  In the case of a high-voltage primary, it is also possible to regulate with a load regulator in the primary, but it is a

expensive solution.

  We can finally work by "wave trains" with a contactor or a circuit breaker acting by "all or nothing" but we have in this case a very high power demand at each engagement, which

  overcurrent on the power grid.

  Finally, the known use of single-phase units coupled

  phased leads, again, at a higher cost than that of an oircuit

three-phase magnetic.

  The purpose of the proposed solution is thus to obtain an apparatus whose cost is lower than that of known heating assemblies, such as for example electric boilers with electrodes which require in particular

plus an isolation transformer.

  And more, to allow the obtaining of a regulation in stages

  sufficiently fine from the power zero up to the maximum power

  male with supportable currents for the power supply. The subject of the invention is thus a thermo-inductive generator for the production of hot fluid, of the short-circuit transformer type comprising a magnetic circuit, a primary winding supplied with

  electrical current and a secondary tubular winding which is electrically

  short circuit and traversed by a fluid to be heated, characterized

  in that said tubular secondary winding comprises a plurality of

  n hydraulically connected tubular elementary circuits

  said tubular elementary circuits comprising means for coupling

  electrical ranges, and in that the different elementary circuits are electrically operated by thyristors controlled by

electronic means.

  According to a preferred embodiment, the n elementary circuits are

  distributed over three columns of a three-phase magnetic circuit.

  Tubular elementary circuits can be connected hydraulically

  electrically in series, in parallel or in parallel series.

  We will now describe a particular embodiment of the invention with reference to the attached drawing in which:

  Figure 1 shows a general view of a thermo-inductive generator.

tif according to the invention.

  Figure 2 shows the same generator as Figure 1 but

  seen from the power supply side of the high voltage outputs.

  FIG. 3 gives an embodiment of assembly of the winding

  secondary showing hydraulic and electrical couplings.

  FIG. 4 is a corresponding electrical and hydraulic diagram

in Figure 3.

  Figure 5 shows the electrical diagram equivalent to the

figure 4.

  FIG. 6 shows the electronic control and control diagram of the thyristors for an assembly comprising four control stages.

  Figures 7 and 8 are flow diagrams.

  The invention can be described as follows, with the help of

Figures 1 to 8.

  On a three-phase magnetic circuit 1 (fig.2) are mounted eoncen-

  trially on each of the three cores a primary winding 2 constituting

  killed by electrical wires and connected to the high-voltage network by plug-in terminals 3 and a secondary winding 4 (fig.1) formed of tubes mounted hydraulically in series, in parallel or in combination

both.

  FIG. 1 illustrates the assembly, by core, of four tubes 5, 6,

7 and 8 in parallel.

  The tubes open into intermediate collectors 9 to 14

  then in general collectors 15 and 16 (fig.3).

  Said tubes are, at least in part, electrically isolated from

  manifolds by sleeves 17, according to the selected electrical coupling.

  FIG. 3 clearly shows the hydraulic assembly in parallel, on each column, of the four tubular elementary circuits 5, 6, 7 and 8 and also of the set of each column, in parallel with the

  collectors 15 and 16. In this way, a sufficient flow rate is ensured.

  at a speed dependent on the installation without loss of load

too important.

  The electrical coupling is achieved by bars 18 to 29, insulating sleeves 17 and groups of thyristors head to tail 30, 31, 32

and 33.

  Figure 4 provides a better view of the electrical circuit. In this diagram, we can clearly see the sets in series, in groups of two, by means of the bars 18 to 23, the tubular elementary circuits 8 and 7 of a

  part and 5 and 6 on the other hand for each column.

  In this scheme, the hydraulic circuit results in a heat exchanger comprising a primary 34 and a second (ire 35. A pump 36

ensures the circulation.

  Figure 5 shows the equivalent electrical diagram of the

  Figure 4, the same references representing the same elements.

  The group of thyristors 30 includes the thyristors 30A and 30B, the -4group 31 the thyristors 31A and 31B, the group 32 the thyristors 32A and

  32B and the group 33, the thyristors 33A and 33B.

  FIG. 6 gives the electronic regulation and control diagram of the thyristors corresponding to FIG. 5, and therefore for the thermoinductive generator represented in the preceding figures.

  In this figure, eight squares, the eight thyris-

  twisted 30A to 33B. These thyristors are controlled by modulators 40,

41, 42 and 43.

  The orders are given by a sequencer 44 which has four

  outputs, one per modulator according to a known principle.

  The usage related information is collected by a regulator 45 which compares the displayed temperature with that measured by

via a probe.

  Figure 7 gives the diagram obtained for 80% of the power and

Figure 8 for 20%.

  The zones marked 61 and 71 give the duration of a cycle in the

two cases.

  The operation of the whole can be decerit as follows

  From the unrepresented supply network, an electric current is injected into the primary winding, a current which generates a field which, via the magnetic circuit, will generate at its

  turn a current in the tubes of the secondary winding.

  The windings of this winding which are short-circuited will heat up and consequently heat the fluid which passes through the tubes and the collectors. This operation is equivalent to that of a transformer whose

  the secondary is loaded resistance bar.

  Ignition of all or part of the thyristors makes it possible to commission one or more secondary winding portions and thus allows regulation, the orders being given by the assembly

  described in relation to FIG.

-5 -

Claims (6)

  1 / thermo-inductive generator for the production of hot fluid of the short-circuit transformer type comprising a magnetic circuit (1), a   primary winding (2) supplied with electric current and a winding   tubular secondary supply (4) electrically short-circuited and   traveled by a fluid to be heated, characterized in that said winding   tubular secondary element comprises a plurality of n elemen-   tubular hoses (5, 6, 7, 8) hydraulically connected (10 to 16),   tubular elementary circuits comprising electrical coupling means   (18 to 29), and in that the individual elementary circuits are electrically operated by thyristors (30 to 33) controlled by electronic means.   2 / thermo-inductive generator according to claim 1, characterized in that the n elementary circuits are distributed over three columns of a three-phase magnetic circuit (1).   3 / thermo-inductive generator according to claim 2, characterized in   the n elementary circuits are hydraulically connected in series.   4 / thermo-inductive generator according to claim 29 characterized in that the n elementary circuits are hydraulically connected in parallel through collectors (9 to 16) of arrival and output. Thermo-inductive generator according to claim 2, characterized in that the n elementary circuits are hydraulically connected in seriesparallel via input and output collectors. exit.   6 / thermo-inductive generator according to one of the preceding claims   characterized in that insulating electrical sleeves (17) are conveniently located between the collectors (9 to 14) and the circuits   tubular elements according to the electrical coupling chosen.   7 / thermo-inductive generator according to one of the preceding claims   characterized in that the electronic control means of the thyristors comprise a regulator (45), a sequencer (44), and modulators (40 to 43).