Untitled record

PATENT

FRENCH REPUBLIC

MINISTRY

INDUSTRY AND TRADE

SERVICE Gr. 5. _ _ΠINDUSTRIAL PROPERTY ^0E%

N ° 1.007.883

Wind installation for isolated operation. (Invention VXtfti ^ dâoMANi.)

Company known as: OFFICE OF SCIENTIFIC AND TECHNICAL STUDIES residing in France (Seine).

Requested April 10, 1948, 10 '¹ 51^m, in Paris.

Issued February 13, 1952. - Published May 12, 1952.

(Patent of invention whose delivery was deferred in execution of article 11, § 7, of the law of July 5, 1844 modified by the law of April 7, 1902.)

The present invention relates to the problem of supplying energy to isolated farms, for example farms, using wind energy for this purpose. In operations of this kind, the energy requirements are generally as follows:

at. Low electrical power continuously available for lighting, the nature of the current being a priori indifferent;

b. A relatively large power available most of the time, preferably in three-phase current of variable frequency and close to 50 pps, but remaining very often unused;

vs. An intermediate power between the previous ones, of any mechanical or electrical form, used whenever it is available to raise the water by means of pumps.

Wind power that exists everywhere seems very suitable to meet these needs. By using electric pumps it will be possible to have a certain latitude in the installation of the wind turbine and it will be ensured that the available power will always be used at least in part. It therefore seems advisable to use a powerful wind turbine, with little variation in speed, operating a three-phase alternator 50 pps, 110 V for needs b and c.

With regard to a it seems essential to have recourse to a storage battery and consequently to use direct current. The production of this current can be obtained by a dynamo which can be used with advantage both as an exciter of the main machine and as a charger.

Direct current can also be obtained by any charger (rectifier, vibrator or converter) from the three-phase.

But the following difficulty presents itself:

If the wheel is capable of starting in very light winds, the accumulators will almost never discharge but the production of three-phase will be poor. In fact, the efficiency of a wheel at constant speed is maximum for a wind speed appreciably 2 - 41044 double the starting speed and decreases beyond that fairly quickly. However, weak winds are insufficient for needs b and c if we want to give the wheel moderate dimensions.

If, on the other hand, we adapt the wind turbine for medium winds we will have an economical wheel for the driving force but immobilizing quite often for a few days and thus risking not ensuring the continuity of the lighting unless we have 'a very strong and therefore very expensive battery. .

The present invention therefore relates to a wind turbine installation for isolated operation which is remarkable in that it comprises, in combination, a large diameter wind turbine, of large power, at approximately constant angular speed, coupled to a three-phase alternator and suitable for medium winds, that is to say for a starting speed of around 4 to 5 m / sec., and a small diameter wind turbine, of low power, with variable angular speed, actuating a dynamo and suitable for very low winds, preferably for a starting speed close to 2 m / sec or even lower.

In order to reduce the cost of a similar installation which would require two pylons and two infrastructures, a particularly advantageous embodiment consists of a combination of only one of the two wind turbines, the small wheel being disposed at the hub of the large one and carried by the same pylon as she. Such a machine constitutes a new industrial product.

There is no disadvantage in thus occupying the central part of the big wheel because the aerodynamic use of the center of the swept circle is always almost zero.

Preferably the large wheel and the small wheel are arranged on either side of the axis of the pylon in order to balance the forces on the latter.

On the other hand, we can remove the rudder

Booklet price: 100 francs.

[1.007.883] orientation by placing the large wheel downwind and the small wheel upwind.

An interesting improvement to this double wind turbine is to rotate the large and the small wheel in opposite directions, and to link the armature of the dynamo to one of them and the inductor to the 'other. With a specially designed dynamo, we manage to remove the drive gears, the effective speed of the dynamo being those added to the big wheel and the small wheel when it should excite the alternator and that of the small wheel only when the large wheel does not rotate, it is only used to charge the batteries.

Yet another improvement resides in that the small wheel is surrounded by a fairing, preferably in the form of a divergent downstream of the small wheel which is disposed substantially at the neck, and preferably preceded by a converging leader.

In the case of a large leeward wheel and a small windward wheel, an annular fairing carried by the large wheel can form an intermediate deflector with a diameter smaller than that of the small wheel and distribute the divergence of the flow.

By way of non-limiting example, there is shown schematically in the single figure of the attached drawing a double wind turbine having the various characteristics mentioned above.

In this embodiment, a large wind wheel, designated as a whole by 1, comprises blades 2 carried externally by a hollow hub 3, the fairing of which diverges from upstream to downstream has a profiled wall. This hub has an internal cross member with profiled arms 4 by means of which it is wedged on a horizontal shaft 5. The central part of the cross member is faired by a warhead 6 which rotates with the wheel 1. The shaft 5 journals in two bearings 7 carried by the two arms of a fork 8 resting on a pivot 9 disposed at the top of a pylon 10. In the axis of the latter is disposed a vertical rotating shaft 11 which crosses the pivot 9 and carries a bevel gear 12 wedged on it engaged with a wheel 13 of larger diameter, with bevel teeth, fixed on the shaft 5. The arms of the fork 8 extend quite high above the shaft 5 and carry a fairing or cover 15, of larger diameter than the hub 3, but also with a profiled wall and diverging from upstream to downstream except in its upstream terminal part which forms a converging primer; at its lower part, this fairing 15 is crossed by a pylon 10 which externally carries a raceway 16 on the opposite faces of which the fairing 15 is supported by rollers 17. At the neck of the converging formed by the fairing 15 is disposed a wind wheel 18 of diameter much smaller than that of the wheel 1. This wheel 18 rests on an extension of the shaft 5 by means of bearings 19; its hub 20 carries one of the elements, 21, armature or inductor, of a dynamo, the other element 22 of which is fixed on the shaft 5; furthermore, the small wheel 18 is established so as to rotate in the opposite direction to the large wheel 1. Upstream of the wheel 18 is disposed the usual distributor 24 fixed to the fairing 15 which carries in its center a bearing 25 supporting the end of the shaft 5. Finally a cover section 26 is fixed to the fork 8 and extends suitably towards upstream the warhead 6; it is itself preceded by a section 27 integral with the wheel 18 and a warhead 28 fixed to the distributor 24.

The whole head of this double wind turbine is thus carried by the fork 8 and is oriented automatically under the action of the wind, without any other rudder. The various elements are established and proportioned to meet the energy needs in each. that particular case that arises, while remaining within the general framework defined in the preamble.

Of course, the invention is in no way limited to the details of embodiment shown or described, which have been given only by way of example.