FR2904896A1 - ARRANGEMENT OF AN ELECTRONIC CIRCUIT IN A ROTATING ELECTRICAL MACHINE AND ROTATING ELECTRIC MACHINE COMPRISING SUCH AN ARRANGEMENT - Google Patents

Abstract

The invention relates to an arrangement of an electronic circuit (201) in a rotating electrical machine, such as an electromagnetic retarder, comprising a wound inductor rotor (101) and a current generator with a feed rotor (124). ) having coils for electrically feeding the wound inductor rotor (101) via the electronic circuit (201) .In accordance with the invention, the electronic circuit (201) is mounted adjacent to the supply rotor (124). also relates to an electromagnetic retarder comprising such an arrangement.

Description

1 Arrangement of an electronic circuit in an electric machine

  TECHNICAL FIELD OF THE INVENTION The present invention relates to an arrangement of at least one electronic circuit in a rotating electrical machine such as an electromagnetic retarder, as well as to a rotating electrical machine comprising such a device. arrangement. STATE OF THE ART Rotating electrical machines, for example electromagnetic retarders, comprise means for creating a stream of a gaseous fluid, typically a stream of air, for cooling the induction coils disposed in a ring on a surface. rotor of the electric machine and inside a stator that surrounds the rotor. When this electric machine is a retarder, the stator is intended to be mounted on a chassis of a vehicle. One of the cooling means is a fan described for example in the documents EP-A-0331559 and FR-A-1467310. In electromagnetic retarders, the fan is also often used to cool other heating elements, for example electronic circuits. Some speed bumps have two fans; they are usually hooked to a retarder shaft. Thus, when a retarder 2 comes into operation, the fan (s) create a stream of air flowing to the retarder coils and to the electronic circuits for cooling. This cooling makes it possible to avoid a fall in performance of the hot retarder. Overall, a fan helps create up to ten percent of the total retarding torque generated by the retarder.

  In recent electromagnetic retarders, because of their architecture, the inductor rotor is powered by a generator, for example a three-phase generator, through one or more rotating diode bridges. The diode bridges, mounted on radiators to ensure their cooling, are placed in a zone through which a cooling gaseous fluid is conveyed by means of the fan or fans of the retarder. Because of the space occupied by the diode bridges with their radiators, these are generally arranged in the rear part of the retarder, seen in the direction of the flow of the gaseous fluid, for example close to the radial fan.

  Thus, the electromagnetic retarders comprise, as described for example in documents FR-A-1 467 730 and EP-BO 331 559, a wound inductor rotor and a current generator provided with a supply rotor for supplying direct current. the coils of the inductor rotor via a rectification component current rectifying device. In these documents, the rectifier is a rectifier bridge carrying rectifying components in the form of diodes 29048963 mounted in pairs, one diode of one pair being connected to ground and the other diode of that pair being connected to ground. supply line of the inductor rotor coils. In the document FR A 1 467 310, the diodes 55 of the rectifier bridge are mounted in a support 56 secured to the front face of the inductor rotor of the retarder (FIG. 1 of the document) so that the diodes are implanted in a hot region. knowing that the coils of the inductor rotor can reach temperatures of the order of 200 C. In the embodiment of Figure 2 of EP-BO 331 559, the diodes 18 of the rectifier bridge are mounted on a web 20 forming 15 mounting flange to a plate secured to the output shaft of the gearbox so that the diodes are located in a region with high mechanical stress. In a variant, as can be seen in FIG. 3 of said document, the diodes are implanted at the inner periphery of the inductor rotor on the side opposite the current generator so that the electrical connections between the diodes and the rotor of the generator are of great importance. length and that the diodes are implanted in a region of high heat. In addition, the diode bridges are cooled with an already hot gaseous fluid, having passed in front of the induction coils of the rotor. If, in addition, the retarder is equipped with a disengageable fan, the diode bridges may not be sufficiently cooled during and especially after use of the retarder. OBJECT OF THE INVENTION The object of the invention is to overcome the various disadvantages mentioned above. More particularly, the invention is intended to provide a solution which makes it possible, if possible, to optimize the mounting of one or more electronic circuits in a retarder, in particular of the components of the rectifier, such as diodes or transistors. of the MOSFET type. Furthermore, it would be desirable to be able to reduce the length of the electrical connections between the components of the electronic circuit (s) and the rotor of the current generator and to reduce the number of connections, on the one hand, and to be able to reduce the mechanical stresses. components, on the other hand. In general, the invention must provide a solution which makes it possible to ensure better cooling of one or more electronic circuits, hereinafter also briefly referred to as electronics, of a rotary electrical machine, for example an electromagnetic retarder, and to reduce the temperature of the components of the electronics, and this with simple, robust, and space-saving means and which, when the solution had to comprise additional parts compared to the fans used before the invention , can be housed inside the electric machine so that they do not contribute to an increase in the size of the electric machine, especially when it is an electromagnetic retarder.

  The object of the invention is achieved with an arrangement of an electronic circuit in a rotating electrical machine, such as an electromagnetic retarder, having a wound inductor rotor and a current generator with a feed rotor. for electrically feeding the wound inductor rotor via the electronic circuit. According to the invention, the electronic circuit is mounted axially adjacent to the supply rotor. The adverb axially is used here as opposed to the adverb laterally and must express that the electronic circuit is disposed substantially within a dummy cylindrical envelope surrounding the feed rotor. This arrangement of the invention brings first the advantage that the length of the electrical connections between the supply rotor and the components of the electronic circuit, for example the rectifying components of a rectifier bridge, is substantially reduced. Another advantage is that the or each of the electronic circuits is close to the supply rotor of the current generator while being implanted in an area not dedicated to a connection in rotation with the retarder shaft, so that this zone is less mechanically stressed. Furthermore, the electronics of the rotating electrical machine 30 are located in a colder zone than that of the wound rotor. In a particular application, where the electric machine is an electromagnetic retarder having a wound inductor rotor and a current generator provided with a supply rotor for electrically feeding the wound inductor rotor via a component current rectifying device The rectifier circuit is a rectifier mounted axially adjacent to the supply rotor. To overcome the drawbacks mentioned above of rotating electrical machines such as retarders used before the invention, the invention therefore proposes in a first embodiment to arrange the electronics in a position axially adjacent to the supply rotor and thus in the front part of the retarder, seen in the direction of the flow of the cooling gaseous fluid, that is to say directly at the inlet of the gaseous fluid in the space to be cooled of the retarder, even before the place where is arranged an axial fan in the retarders used before the invention.

The arrangement of the electronics in front of an electromagnetic retarder cleverly utilizes the retarder design. The retarder comprises a rotating shaft adapted to be hooked to a main or secondary output shaft of a gearbox, to an input shaft of a rear axle of a motor vehicle, to a rear axle of a trailer or semi-trailer or to a speed-increasing gearbox, as well as a rotor integral in rotation with the rotating shaft, induction coils disposed in a ring on the rotor and inside a stator surrounding the rotor and intended to be mounted on a chassis of the vehicle, a generator mounted on one end of the rotating shaft of the rotor and supplying the induction coils, and an axial-acting fan for introducing a fluid gaseous cooling inside the retarder and to circulate on the induction coils and electronics. The output of the gaseous fluid is assisted by means giving the flow of the gaseous fluid a transverse orientation with respect to the axis of the retarder. Instead of cooling the electronics, as before the invention, by a gaseous fluid already heated, since passed in front of the induction coils, the invention therefore has the electronics in a place where the gaseous fluid is not still heated, that is to say before the induction coils. The invention thus makes it possible to increase the performance and the reliability of the retarder by better controlling the cooling of the electronics. The solution that the invention proposes, is simple to integrate into the design of a retarder, 20 is not bulky, is lightweight and very economical. The invention also relates to the features hereafter considered in isolation or in any technically possible combination. the or each of the electronic circuits is disposed, seen in the direction of the flow of cooling gaseous fluid, alternately at the front or rear of the rotor of the generator of the rotating electrical machine; the or each of the electronic circuits is disposed inside the body of the rotor of the generator of the rotating electrical machine, that is to say, it is or they are implanted in the thickness of the body supply rotor; The or each of the electronic circuits is integral with the body of the supply rotor; the or each of the electronic circuits forms a unitary assembly with the body of the supply rotor; The electronic circuit is a current rectifying device comprising two radiators, respectively a negative radiator intended to be connected to ground and a positive radiator electrically insulated with respect to the body of the supply rotor; the electronic circuit is mounted on one or more supports forming one or more radiators, the or each of the radiators being provided with ridges for increasing the exchange surface; The negative radiator is also electrically insulated with respect to the body of the supply rotor when the latter must not be connected to ground; the radiators are made of metal to better evacuate the heat; the diodes are mounted by force-fitting in the radiators and comprise for this purpose a knurled body; - alternatively, the diodes are reported by brazing on the radiators; the radiators are provided with radial fins or radial ribs to both increase the heat dissipation and channel the flow of a gaseous cooling fluid, the radiators thus forming a radially-acting fan; the stator feed body is mechanically connected to the body of the stator wound by tie rods; a fan is associated with the straightening device; The generator stator hood is pierced centrally in order to channel the flow of a cooling gaseous fluid, generally air, from licking the radiators (ribbed or finned) of the components of the electronic circuit, for example a current rectifying circuit; the circulation of the cooling gaseous fluid is caused by a larger diameter fan than that of the feed rotor body; thanks to this arrangement, the bunks of the generator rotor of the generator are well cooled.

Of course, the number of components of the electronic circuit or circuits, for example of one or more rectification bridges, depends on the number of phases of realization of the generator. In the example shown, the generator is of the three-phase type. Alternatively, the generator may have 5, 6 or 7 In body of the wound rotor, is a rotor with salient poles. In a variant, this body is grooved for assembling windings with at least two stages, as described in document FR A 1 467 730. The object of the invention is also achieved with an electromagnetic retarder in which the electronics is arranged as described above. BRIEF DESCRIPTION OF THE DRAWINGS Other features and advantages of the present invention will become apparent from the description of the phases. the exemplary embodiment of the feed rotor, all shown, the like the body 2904896 10 hereafter of an embodiment of the invention, this description being made with reference to the accompanying drawings in which. FIG. 1 is a perspective view, with local cutaway, of an electromagnetic retarder having a plurality of fans mounted on a rotating shaft of the retarder integral with an output shaft of a gearbox; FIG. perspective view, with local cutaway, of one of the two ends of a retarder of the invention, end which comprises an arrangement of electronic circuits according to a preferred embodiment of the invention, - Figure 3 is a view in perspective, with local detachment, of the retarder of FIG. 2, shown with a view of the other of the two ends of the retarder and a representation of the cooling flow, FIG. 4 is a perspective view, with axial section, of the retarder 2, with a view of the same end of the retarder as in FIG. 3, FIG. 5 is a view in axial section of the retarder of FIG. 2, showing the arrangement of electro circuits. According to the invention and the flow of a cooling gaseous fluid through the retarder of FIG. 1, FIG. 6 is a perspective view of the insulating support of the radiators of the rectifier bridge, and FIG. perspective view of current rectifier bridge radiators equipped with diodes.

These figures are given by way of illustration and are not limiting of the invention. In these figures, identical or similar elements will be assigned the same reference signs. DESCRIPTION OF A PREFERRED EMBODIMENT OF THE ARRANGEMENT ACCORDING TO THE INVENTION FIG. 1 recalls the general structure of an electromagnetic retarder with two fans mounted on a rotating shaft of the retarder. The electromagnetic retarder is shown in perspective view with axial partial section and as being mounted on a gearbox 105 of a motor vehicle. This retarder is intended to slow down a transmission shaft of the vehicle and more particularly here the output shaft of the gearbox 105, here via a speed multiplier described for example in the document FR-A-2861912 to which reference will be made by generating an alternately distributed magnetic field in an internal ferromagnetic part 121 of a stator 110 which also comprises a cooling jacket 103 in helical form in a single turn. The jacket 103 is provided with an intake duct C and an exhaust duct D. The jacket 103 delimits, with the inner part 121, a chamber inside which a cooling fluid circulates, here that of the engine of the vehicle. The retarder comprises a rotating shaft 102 hooked to the output shaft of the gearbox 105 and a rotor 101 integral in rotation with the rotating shaft 102. Induction coils 107 are arranged in a ring on the rotor 101 and inside the stator 110 surrounding the rotor 101. The stator 110, which includes the cooling water jacket 103 and the inner part 121, is intended to be mounted on a chassis of the vehicle. The retarder also comprises a current generator 106, here of the three-phase type, mounted on one end of the rotating shaft 102 of the rotor 101, a rotor 124 (see FIGS. 2 and 3) constituting an armature of the generator 106 and two fans 108 and 109A for circulating a cooling gaseous fluid, generally air, on the induction coils 107, thus for cooling the rotor 101. The fan 109A is axially acting while the fan 108 is radially acting, that is to say of the centrifugal type, the blades of these two fans being configured accordingly. Fan 109A is disengageable in this embodiment. The generator 106 provides the excitation energy necessary to generate the alternating distribution magnetic field. This generator 106 comprises an inductor stator formed by a ring 25 of coils or windings 104 of electrical wires around nuclei constituting multiple magnetic poles with alternating polarities, and the induced rotor 124. This induced supply rotor 124 comprises a body, here in the form of a bundle of sheets, as can be seen in FIGS. 2 and 3. This body is provided with grooves for the mounting of induced coils or, alternatively, of two-stage windings as described in document FR-A A-1 467 730. The rotor 124 is connected to the rotor 101 by tie rods. The inductor stator surrounds the induced rotor with a low air gap. A rectifier bridge 201 is interposed between the induced rotor of the generator 106 and the coils, as described in documents EP-A-0331559 and FR-A-1467310.

The coils 104 are powered by a DC power source such as a vehicle battery equipped with the retarder. The intensity of this current is adjusted according to the resistant resisting torque that the retarder must produce. In fact, by adjusting the intensity of the induction current of the coils 104, the intensity of the electric current generated by the induced rotor of the generator 106 is regulated, and, finally, the intensity of the eddy current generating torque slow-down and heating resistor 15, generated in the ferromagnetic part 121 of the stator 110 of the retarder. The generation of the electric supply current required for the generation of eddy currents by a generator 106 integrated in the retarder provides a twofold advantage. The first advantage consists in a very low external electrical energy input taken from the vehicle battery, for example of the order of 20 to 30% of the total energy required. The second advantage is that the generation of the electric current by the generator itself consumes some mechanical energy taken from the tree to slow down.

The excitation current generated by the induced rotor 124 of the generator 106 supplies the induction coils 107 of the retarder rotor 101 to generate a magnetic field. The coils 107 are formed by windings of electrical wires 35 around cores forming integral parts of the rotor 101. The cores belong to the body of the rotor 101 made of ferromagnetic material and form salient poles. The magnetic field induces the stator 110 of the retarder and generates eddy currents therein, in particular in the inner part 121 of the stator 110 made of a ferromagnetic material. The eddy currents being opposed, by their effects, to the cause that gives them the meaning, namely the rotational movement of the rotor, the rotational movement of the rotor 101 thus generates an inverse torque of rotation, thus a resisting torque of Slowdown of the shaft 102. Note that the body of the rotor 101 is made of ferromagnetic material and here consists of a package of 15 sheets. The generation of eddy currents being accompanied by a heating, by Joule effect, in particular of the inner part 121 of the stator 110, this part is cooled by the fluid flowing in the cooling jacket 103. At the same time, there is creating a stream of air inside the retarder, under the action of the fans 108 and 109A. Air enters the retarder axially through a perforated lid 113 under the action of the fan 109A, then circulates inside the retarder cooling including the coils 107 to be finally discharged radially by the rear fan 108, centrifugal type , through a perforated support 114.

Note that the fan 109A has blades whose feet are anchored in a sleeve 111 inside which is mounted a bearing, here a ball bearing (not visible), intervening between the outer periphery of the shaft 102 and the inner periphery of the sleeve 111. The heads of the blades are anchored in an outer peripheral ring 119. The fan 109A is a disengageable fan. This fan is engaged when the coils 107 are electrically powered, i.e. when the retarder is operating. The fan is disengaged, being free to rotate through the aforementioned bearing, when the retarder does not work, that is to say when the coils 107 10 are not electrically powered. To do this, the fan 109A carries a ring 112 made of ferromagnetic material, which extends below the heads of the coils 107. Thus, when the coils 107 are electrically powered, a magnetic field is generated which allows a magnetic looping with the ring 112. This looping rotates the fan 109A axial action which rotates with the stator 110 and the shaft 102 of the retarder.

The fan is then engaged; otherwise it is disengaged and does not rotate with the stator 110 and the shaft 102. The fan 109A is of small axial size and reduces the no-load losses and the consumption of a torque on the shaft 102 during the periods non-use of the retarder. For the purposes of the following description, the end of the retarder through which the air enters the retarder, here constituted by the perforated cover 113, is called the front of the retarder, and the opposite end , here constituted by the perforated support 114, is called the back of the retarder. The cover 113 and the support 114 are fixed for example by screwing onto the cooling jacket of the retarder.

Figure 2 is a perspective view, locally broken away, of the front of a retarder according to the invention with a fan 109 not disengageable. This figure shows more particularly an arrangement of electronic circuits, here a current rectifying bridge 201, for supplying DC current to the coils 104 of the generator 106, according to the preferred embodiment of the invention.

Indeed, the present invention proposes to arrange the retarder electronics in a position adjacent to the feed rotor 124 and thus in the front portion of the retarder. The rectifier bridge 201 is mounted on a disc-shaped support 202 which is disposed at the front of the generator 106 and has a central and external peripheral return (see FIG. 4) as well as ears 302 enabling it to be mounted just behind. the perforated lid 113.

It will be noted that the support 202 is made of electrically insulating material, here made of plastic material. This support 202, in hollow form, has at its outer periphery four perforated ears 302 (see FIG. 6) for fixing it by means of screws or rivets to the body of the induced rotor supply 124. The ears 302 are angularly distributed at 90 with respect to each other. Two of these diametrically opposed lugs 302 are radially inwardly extended by separation ribs 303. These ribs 303 serve to separate the two radiators 304, 305 (see FIG. 7) from the rectifier bridge 201. The radiators 304 305 are metallic and each extend generally 180 as can be seen in FIG. 7. They comprise notches for the passage of the fastening lugs 302. The heatsink radiators 304, 305 are each fixed on the front face of the insulating support 202, stiffened by its flanges, 5 for example using screws not shown. The radiators 304, 305 are in contact with the front face of the support 202 belonging to the disk thereof. The radiators 304, 305 each carry current rectifying elements, here in the form of diodes. The rectifier bridge 201 comprises branches, here four branches, each comprising two diodes connected in series between the ground and a supply line of the coils 107 as visible for example in the documents FR-A-1 467 310 and EP-B -0 331 559. Compared to these two documents, there are six diodes and two additional diodes, called freewheeling. The six diodes are mounted in pairs at the rate of two diodes per branch. One of the 20 radiators, for example the radiator 304, carries the so-called negative diodes, intended to be connected to ground, and the other of the radiators, therefore the radiator 305, carries the other diodes, that is to say say the so-called positive diodes. The diodes have a knurled body for forced fitting into the radiator 304, 305, and an axially oriented shank (see FIG. 4). The tails of the diodes pass through the support disk which carries, at its rear face, metal traces 30 (not shown) for interconnecting the diodes. It is interesting to note here that the cover 113 has a substantially planar disc portion 115, an outer rim 116 facing rearward of the retarder and a central recess or recess 117, also facing rearwardly of the retarder and contributing to forming a front bearing for the rotating shaft 102. While the disc portion 115 and the rim 116 5 are fully closed, the recess 117 is provided with inlet openings 118 distributed in a ring around the opening of the cover 113 allowing access of a cooling gaseous fluid inside the retarder. More specifically, the depression has at its inner periphery a bushing, as can be seen in FIGS. 4 and 5. A bearing, such as a ball bearing 301, is interposed radially between the outer periphery of the front end of the bushing. shaft 102 and the inner periphery 15 of the depression, which thus has a dual function. It should be noted that the shaft 102 has a corrugated rear end (see FIGS. 3 to 5) for complementary engagement with a corrugated internal bore provided by a gear 20 belonging to a speed multiplier mentioned above between the shaft 102 and a gearbox. secondary shaft of the gearbox connected to the main output shaft of the gearbox. Slowing down the shaft 102 causes the secondary and main shafts of the gearbox to slow down and thus to slow down the motor vehicle. Furthermore, each radiator 304, 305 of the rectifier bridge 201 is provided with fins or ribs 204 disposed radially around the central opening of the support. Thus, each radiator forms a radially-acting fan guiding the gaseous fluid, entering via the inlet openings 118, along the radiators of the rectifier bridge 201 to cool them, before the rim 116 of the lid 2904896 19 opens 113 directs the gaseous fluid to the coils 104 of the generator 106 and then to the inside of the retarder. Each diode body is implanted between two ribs 204 and is thus well cooled. Consequently, the exclusive arrangement of the inlet openings 118 on the depression 117 of the cover 113 contributes significantly to a reduction of the aeraulic losses due to the reorientation of the flow of gaseous fluid arriving at the retarder with an axial orientation and landing on the radiators and the support 202. The axial inlet and the radial distribution of the flow of the cooling gaseous fluid are indicated in FIGS. 2, 3 and 5 by straight and curved arrows. It is easy to understand that, in an alternative arrangement of the electronic circuits, the support 202 with the rectifier bridge 201 can also be mounted at the rear of the generator supply rotor or inside the rotor body. power supply of the generator of the rotating electrical machine. In the latter case, the rectifier bridge is implanted in the thickness of the feed rotor body. Advantageously, the diodes consist in this case in parts devoid of orientation tails. However, whatever the arrangement of the rectifier bridge 201, the coolant gas flow first meets the radiators of the rectifier bridge 201 and its support 202 and cools them before entering the retarder to cool the coils. induction of the retarder rotor. According to an alternative embodiment, not shown in the drawings, the face of the radiators 2904896 20 of the rectifier bridge 201 which is exposed to the flow of gaseous fluid, may be provided with ridges to increase the exchange surface. Figure 3 is a perspective view, with local cutaway, of the retarder of Figure 2, with a view of the rear end of the retarder and representation of the flow of gaseous cooling fluid within the retarder. At the inlet of the retarder, there is found the supply rotor 124 of the generator and the rectifier bridge (not visible here), then, in the axial assembly order, the axial-action fan 109 and the rotor with the induction coils 107 surrounded by the stator 110 of the retarder and in particular 15 of the cooling jacket 103. The flow of gaseous cooling fluid passes through the coils 104 of the generator rotor 106 and is then accelerated by the fan 109 through the induction coils 107 of the retarder rotor. Thus, the cooling gaseous fluid successively cools, on its path in the form of a cylindrical envelope, the coils 104 of the generator 106 with the rectifier bridge 201, and the induction coils 107 before leaving the inside of the retarder by the It will be noted that the outer ring 119 of the fan extends above the gap between the stator coils 104 and the rotor windings of the generator 106. (see FIG. 4).

FIG. 4 is a perspective view, with axial section, of the retarder of FIG. 2, with a view of the rear end of the retarder. At the inlet of the retarder, there is found the perforated cover 113 and then, in the axial assembly order, the rectifier bridge 201 with its support 202, the rotor 2904896 21 for supplying the generator 106 with its coils, the axial-action fan 109 and the rotor with the induction coils 107 surrounded by the stator 110 of the retarder and in particular the cooling jacket 103. FIG. 4 shows more particularly the shape of the depression 117 of the perforated cover 113 and the shape of the central return 203 of the support 202 of the rectifier bridge 201. The depression 117 forms, with a bearing ring 301, the front bearing of the rotating shaft 102 of the retarder. At the same time, the shapes of the central return 203 and the recess 117 allow a compact arrangement of the rectifier bridge 201 and the feed rotor of the generator 106 while creating an optimal path, and particularly effective for cooling the bridges. rectifiers 201, for the passage of cooling gaseous fluid. FIG. 5 is an axial sectional view of the retarder of FIG. 2, showing the arrangement of electronic circuits according to the invention and the flow of a gaseous cooling fluid through the retarder of FIG. more particularly, at the inlet of the retarder, the perforated cover 113 and then, in the axial assembly order, the rectifying bridge 201 with its support 202, the rotor of the generator 106 with its coils, the fan with axial action 109, mounted on an annular spacer 209, and the rotor with the induction coils 107 surrounded by the stator 110 of the retarder and in particular the cooling jacket 103. Fixing members such as tie rods pass through the spacer 209 for fixing the bodies of rotors 101 and 124 with the spacer.

In particular, FIG. 5 shows the flow of a gaseous fluid cooling through the retarder and in particular in front of the support 202 of the rectifier bridge 201 to cool it first. The gaseous fluid, generally air, arrives at the cover 113 and enters the retarder through the inlet openings 118 of the cover 113, that is to say in the form of as many partial flows as the cover 113. Each of the partial flows enters the retarder with a non-axial orientation, essentially determined by the arrangement of the corresponding inlet lug 118 in the curved portion of the depression 117 of the lid 113. .

The set of partial flows forms a cooling jacket for the generator 106 and the rectifier bridge 201 and a cylindrical cooling flow axially passing through the induction coils 107 of the retarder rotor.

Once again, we see the merit of the invention which consists in arranging the electronics of the retarder, here the rectifier bridge 201 with its radiators and their support 202, at the front of the retarder, adjacent to the supply rotor of the retarder generator 106 so that the cooling gaseous fluid first passes the rectifier bridges 201 to cool them before entering the interior of the retarder rotor to cool the induction coils 107 therein.

Of course, the present invention is not limited to the embodiment described or its variants described. Thus, the non-disengageable fan 109 can be replaced by a disengageable fan 109A, thanks to the crown 112, at least two stages to improve the performance of the fan and reduce the no-load losses. Such a fan facilitates cooling of the coils, while limiting the consumption of a torque on the shaft, especially during periods of non-use of the retarder. For this purpose, such a fan comprises a hub and at least two sets of blades arranged radially around the hub. The first set of blades is disposed directly around the hub and forms a first stage of the fan, and the one or more other sets of blades are arranged around the first set of blades and successively form, towards the outside of the fan, a second stage. , a third floor etc. of the fan, each stage having a number of blades greater than that of the lower stage. The design of a fan with at least two stages also makes it possible to optimize the efficiency of the fan by varying the inclination of the blades from the center to the periphery.

In general, with the fan 109 declutchable one or two stages, the invention provides a solution to improve the performance of the retarder, including reducing the no-load losses. In other words, the invention facilitates the cooling of the retarder electronics, while limiting the consumption of a torque on the shaft, especially during periods of non-use of the retarder.

Claims (17)

  An arrangement of an electronic circuit (201) in a rotating electrical machine, such as an electromagnetic retarder, having a wound field rotor (101) and a current generator having a feed rotor (124) having coils for electrically feeding the wound inductor rotor (101) via the electronic circuit (201), characterized in that the electronic circuit (201) is mounted adjacent to the supply rotor (124).   2. Arrangement according to claim 1, characterized in that the electronic circuit (201) is disposed at the front of the rotor (124) of the rotating electrical machine, seen in the direction of the flow of a cooling gaseous fluid .   3. Arrangement according to claim 1, characterized in that the electronic circuit (201) is disposed at the rear of the rotor (124) of the rotating electrical machine, seen in the direction of the flow of cooling gaseous fluid.   4. Arrangement according to claim 1, characterized in that the electronic circuit (201) is disposed within the body of the supply rotor (124) of the rotating electrical machine.   5. Arrangement according to any one of claims 1 to 4, characterized in that the electronic circuit (201) is integral with the body of the feed rotor (124).   An arrangement according to any one of claims 1 to 4, characterized in that the electronic circuit (201) forms a unitary assembly with the body of the feed rotor 2904896 (124).   7. Arrangement according to any one of claims 1 to 6, characterized in that the electronic circuit (201) is a current rectifier device comprising two radiators (304, 305), respectively a negative radiator intended to be connected to the mass and a positive radiator electrically isolated from the body of the supply rotor. 10   8. An arrangement according to claim 1 with an electronic rectification circuit comprising respectively a negative radiator and a radiator according to any one of the 6, characterized in that the (201) is a device of two radiators (304, 305), two positive, the electrically powered.   9. The energeters are isolated relative to the rotor body according to claim 7 or 8, characterized in that the radiators (304, 305) are made of metal.   An arrangement according to any one of claims 7 to 9, characterized in that the electronic circuit (201) comprises diodes having a knurled body to be press fit into the radiators (304, 305).   11. Arrangement according to any one of claims 7 to 9, characterized in that the electronic circuit (201) comprises diodes reported by brazing on the radiators (304, 305).   An arrangement according to any one of claims 7 to 11, characterized in that the radiators (304, 305) are provided with fins (204) or ribs for channeling the flow of a cooling gas fluid. 2904896 26   Arrangement according to any one of the preceding claims, characterized in that the body of the feed rotor (124) is mechanically connected to the body of the wound stator by tie rods.   14. Arrangement according to any one of the preceding claims, characterized in that a fan (109) is associated with the electronic circuit (201). 10   15. Arrangement according to any one of the preceding claims, characterized in that the cover (113) of the stator of the generator is centrally perforated for channeling the gaseous cooling fluid licking the ribbed radiators or finned components of the electronic circuit (201).   16. An electromagnetic retarder having a rotating shaft (102) with means (109) for circulating cooling gaseous fluid on induction coils (107) for generating, upon command, eddy currents in a stator (110). ) surrounding the rotating shaft (102) and the induction coils (107), characterized in that it comprises at least one electronic arrangement according to one of 1 to 15.   17. Retarder (201) disposed according to any one of the electromagnetic claims according to claim 16, characterized in that the means (109) for circulating a cooling gaseous fluid is a fan of larger diameter than that of the rotor body. food.