Title of Invention

A BRUSHLESS POLYPHASE AC GENERATOR

Abstract

A brushless polyphase AC generator, the brushless polyphase AC generator including a stator (50) and its winding (53); a cylindrical rotor (60) having a plurality of permanent magnets (62) each disposed in the circumferential direction and rotating relative to the stator; magnetic pole sensors (29) for detecting the rotary position of a rotor, wherein a phase current is supplied to each phase of the windings for angle-advancement according to the detection signal of the magnetic pole sensor, the rotor has an interpole portion (613) between each adjacent two of the permanent magnets, wherein the phase current supplied to each phase is angle advanced though a amount of angle represent a circumferential width of the interpole portion so that the timing with which the phase current is supplied may coincide with the timing with which the magnetic field detected by the magnetic pole sensor is changed.

Full Text

FORM 2 THE PATENTS ACT, 1970 [39 OF 1970] THE PATENTS RULES, 2003 COMPLETE SPECIFICATION [See Section 10; rule 13] "A BRUSHLESS POLYPHASE AC GENERATOR" HONDA GIKEN KOGYO KABUSHIKI KAISHA, of 1-1, Minamiaoyama 2-chome, Minato-ku, Tokyo, Japan, The following specification particularly describes the nature of the invention and the manner in which it is to be performed:- Technical Field The present invention relates to a brushless polyphase AC generator and an excitation control apparatus therefor and, more particularly, to a brushless polyphase AC generator and its excitation control apparatus that are suitable for excitation made for causing the advancement of the object angle. Background Art Conventionally, a starter motor and generator for use on an internal combustion engine were individually separately equipped. However, for example, the official gazette of Japanese Patent Application Laid-Open No. Hei-10-148142 discloses a starter / generator system wherein the function of the starter and that of the generator have been integrated with each other. On the other hand, as a starter motor for use on the internal combustion engine there is known an external-rotation permanent magnet type rotary electric machine having a cylindrical rotor that rotates around the outer-periphery of the stator. Also, in such a permanent magnet type rotary electric machine, in order to mitigate the distortion of the magnetic flux between the rotor and the stator and thereby prevent the occurrence of the torque vibrations, for example the official gazette of Japanese Patent Application Laid-Open No. Hei-8-275476 discloses a permanent magnet type rotary electric machine wherein an interpole portion is formed between adjacent two of the permanent magnets. In the conventional permanent magnet type rotary electric machine equipped with the interpole portions, these interpole portions function as part of the permanent magnets, too. For this reason, regarding the timing at which excitation is made to the rotary electric machine, it is preferable that the object angle be advanced through an angle corresponding to the width in the rotation direction of the interpole portion. In the prior art, the standard excitation timing (0° object angle) is detected as the change in the detection signal of a magnetic pole sensor and, according to this standard excitation timing, the position at which the object angle is to be advanced was determined through the performance of a relevant calculation. Therefore, especially in a low-rotation range in which the rotor rotations number becomes unstable, the object-angle advance position could not be accurately obtained. An object of the present invention is to provide a brushless polyphase AC generator and its excitation control apparatus that have been arranged so that the phase current supplied to each phase may enable only a prescribed angle to be accurately advanced. Disclosure of Invention To attain the above object, the present invention has features in the respect that the following measures have been taken. (1) A brushless polyphase AC generator including magnetic pole sensors each for detecting the rotary position of a rotor and including a plurality of phases to each of that a phase current is supplied, the phase current having its supply timing angle-advanced through a prescribed amount of angle according to the detection signal of the magnetic pole sensor. Each of the magnetic pole sensors is disposed so' that the timing with which the phase current is supplied for angle advancement may coincide with the timing with which the magnetic field detected by the magnetic pole sensor is changed. (2) An excitation control apparatus for the brushless polyphase AC generator having themagneticpole sensors according to the output signal from each of that one full rotation of the rotor is divided into a plurality of stages, whereby the respective phase currents are controlled in units of the stage. The phase of the phase current supplied to each phase is angle advanced by a half of the angular range corresponding to the one stage. According to the above-described feature (1), when the rotation position of the rotor has reached changeover timing for the excitation made for causing the advancement of the object angle, in response thereto the detection signal of the magnetic-pole sensor changes. Therefore, the changeover timing for advancement of the retard angel can be accurately detected according to the detection signal of the magnetic-pole sensor. According to the above-described feature (2), when the rotation position of the rotor has reached changeover timing for the excitation made for causing the advancement of the object angle not only at the time of normal-rotation of the rotor but also at the time of reverse-rotation thereof, in response thereto the detection signal of the magnetic-pole sensor is displaced. Therefore, it is possible to accurately detect the changeover timing for angle advance. Brief Description of Drawings Fig. 1 is an entire side view of a scooter type two-wheeled motor vehicle of the present invention; Fig. 2 is a sectional view of a swing unit shown in Fig. 1, taken along a crank shaft; Fig. 3 is a partially cut-away plan view taken along a plane perpendicular to a rotary shaft (crank shaft) of a combined starter/generator (a permanent magnet type rotary electric machine); Fig. 4 is a sectional side view of Fig. 3; Fig. 5 is a plan view of a rotor yoke; Fig. 6 is a side view of the rotor yoke; Fig. 7 is a partial enlarged view of the rotor yoke; Fig. 8 is a view illustrating the function (during the supply of the power) of the gap portions provided in the rotor yoke; Fig. 9 is a view illustrating the function (during the generation) of the gap portions provided in the rotor yoke; Fig. 10 is a partially enlarged view of Fig. 9; Fig. 11 is a partially enlarged view of Fig. 10; Fig. 12 is a block diagram of a control system for the combined starter/generator; Fig. 13 is a view typically representing the operation timing in an embodiment of the present invention with which the excitation is controlled; Fig. 14 is a signal waveform diagram illustrating a case where excitation for normal rotation through an angle of 120° has been executed with the advancement of 5° object angle; Fig. 15 is a signal waveform diagram illustrating a case where excitation for normal rotation through an angle of 180° has been executed with the advancement of 10° object angle; and Fig. 16 is a signal waveform diagram illustrating a case where excitation for reverse rotation through an angle of 120° has been executed with the advancement of 5° object angle. Best Mode for Embodying the Invention The present invention will be described in detail herein with reference to the drawings. Fig. 1 is an entire side view of a scooter type two-wheeledmotor vehicle to which the vehicular power generation control unit of the present invention is applied. Front and rear portions of a vehicle body are connected together through a low floor portion 4. A body frame serving as a skeleton of the vehicle body is roughly composed of down-tubes 6 and main pipes 7. A fuel tank and a container box (neither shown) are supported by the main pipes 7 and a seat 8 is disposed thereon. In the front portion of the vehicle body, a handlebar 11 is supported by and above a steering head 5 through a shaft, while a front fork 12 extends downward from the steering head and a front wheel FW is supported through an axle at a lower end of the front fork 12. The handlebar 11 is covered from above with a handlebar cover 13 which also serves as an instrument panel. Brackets 15 are projected from lower ends of rising portions of the main pipes 7 and hanger brackets 18 of a swing unit 2 are respectively connected to and supportedby the brackets 15 swingably through link members 16. A single-cylinder two-stroke internal combustion engine E is mounted on a front portion of the swing unit 2. A belt type continuously variable transmission 10 is constituted backward from the engine E and a reductionmechanism 9 is connected to a rear portion of the continuously variable transmission 10 through a centrifugal clutch, with a rear wheel RWbeing supported by the reduction mechanism 9 though an axle. A rear cushion 3 is disposed between an upper end of the reduction mechanism 9 and an upper bent portion of a main pipe 7 . In the front portion of the swing unit 2 are disposed a carburetor 17 connected to an intake pipe 19 extending from the engine E and an air cleaner 14 connected to the carburetor 17. Fig. 2 is a sectional view of the swing unit 2 taken along a crank shaft 201, in which the same reference numerals or marks as above represent the same or equivalent portions. The swing unit 2 is covered with a crank case 202 which is constituted by combining left and right crank cases 202L, 202R with each other. The crank shaft 201 is supported rotatably by bearings 208 and 209 which are fixed to the crank case 202R. A connecting rod (not shown) is connected to the crank shaft 201 through a crank pin 213. The left crank case 202L also serves as a belt type continuously variable transmission case and a belt driving pulley 210 is mounted rotatably on the crank shaft 201 which extends up to the left crank case 202L. The belt driving pulley 210 comprises a fixed pulley half 210L and a movable pulley half 210R. The fixed pulley half 210L is fixed to a left end portion of the crank shaft 201 through a boss 211 and the movable pulley half 210R is splined to the crank shaft 201 on the right-hand side of the fixed pulley half 210L so as to be movable toward and away from the fixed pulley half, A V belt 212 is entrained between both pulley halves 210L and 210R. On the right-hand side of the movable pulley half 210R a cam plate 215 is fixed to the crank shaft 201 and a slide piece 215a provided an outer periphery end of the cam plate 215 is slidably engaged with a cam plate sliding boss portion 210Ra formed axially at an outer periphery end of the movable pulley half 210R. The c^m plate 215 located on the right-hand side of the movable puUey half 210R has a tapered outer periphery surface inclined toward the movable pulley half 210R and a dry weight ball 216 i$ accommodated in a space formed between the tapered surface and the movable pulley half 210R. As the rotational speed of the crank shaft 201 increases, the dry weight ball 216 located between the movable pulley half 210R and the cam Plate 215 and adapted to rotate together with them moves in a centrifugal direction with a centrifugal force and the movable Pulley half 210R is pushed by the dry weight ball 216 and moves leftward, approaching the fixed pulley half 210L. As a result, the V belt 212 sandwiched in between both pulley halves 210L and 210R moves in a centrifugal direction and its winding diameter becomes larger. In the rear Portion of the vehicle is provided a driven pulley (not shown) in a corresponding relation to the belt driving pulley 210 and the v belt 212 is entrained on the driven pulley. With this belt transfer mechanism, the power of the engine E is regulated automatically and is transmitted to a centrifugal clutch to drive th^ rear wheel RW through the reduction mechanism 9, etc. A combined st^rter/generator 1 as a combination of a starter motor and an AC generator is disposed within the right crank case 202R. In the combined starter/generator 1, an outer rotor 60 is fixed with q screw 253 to a tapered front end portion of the crank shaft 201 and an inner stator 50, which is disposed inside the outer rotor 60, is secured to the crank case 202 threadedly withbolts 279. As to the construction of the combined starter/generator l, it will be described in detail later with reference to Figs. 3 to 7. A fan 280 has a central conical portion 280a, a skirt portion of which is fixed to the outer rotor 60 with bolts 24 6, and the fan 280 is covered with a fan cover 281 through a radiator 282. A sprocket 231 is fixed onto the crank shaft 201 at a position between the combined starter/generator 1 and the bearing 209 and a chain for driving a cam shaft (not shown) from the crank shaft 201 is entrained on the sprocket 231. The sprocket 231 is integral with a gear 232 which is for the transfer of power to a lubricating oil circulating pump. Figs. 3 and 4 are respectively a partially cut-away plan view taken along a plane perpendicular to a rotary shaft (crank shaft 201) of the combined starter/generator 1 (a permanent magnet type rotary electric machine) and a sectional side view thereof, and Figs. 5 and 6 are respectively a plan view of a rotor yoke and a partially enlarged view thereof, in which the same reference numbers or marks as above represent the same or equivalent portions. As shown in Figs. 3 and 4, the starter/generator 1 according to this embodiment is composed of a stator 50 and an outer rotor 60 adapted to rotate along an outer periphery of the stator 50. The outer rotor 60 is made up of an rotor yoke 61 formed by laminating ring-like silicon steel sheets in a generally cylindrical shape, as shown in Figs. 4 and 5, N-pole permanent magnets 62N and S-pole permanent magnets 62Sinsertedalternately within plural apertures 611 which are formed in the circumferential direction of the rotor yoke 61, as shown in Figs . 3 and 7, and a cup^iike rotor case 63 which connects the rotor yoke 61 to the crank shaft 201, as shown in Figs. 3 and 4. The rotor case 63 is provided with a pawl portion 63a at a circumferential end thereof. By bending the pawl portion 63a inwards, the rotor yoke 61 of the aforesaid laminated structure is held grippingly in the axial direction thereof and the permanent magnets 62 (62N, 62S) inserted into the apertures 611 of the rotor yoke §i are held at predetermined positions in the rotor yoke 61. The stator 50 is constituted by laminating silicon steel sheets and includes a stator core 51 and stator salient 52, as shown in Fig. 3 . A. stator winding 53 is entrained on each stator salient 52 in a singie-pole concentratedmanner and amain surface of the stator 50 is covered with a protective cover 71. As shown in Figs. 5 and 6, twelve apertures 611 for axial insertion therein of permanent magnets 62 are formed at intervals of 30° in the circumferential direction. The portion between adjacent apertures 611 functions as an interpole 613. As shown in Fig. 7, permanent magnets 62 each having a generally drum-like section are inserted into the apertures 611 respectively. In this embodiment the shape of each aperture 611 and the sectional shape of each permanent magnet 62 are not the same. With the permanent magnets 62 inserted into the apertures 611, first gaps 612 are formed in both side portions in the circumferential direction of each permanent magnet 62 and second gaps 614 are formed on the stator side at both end portions of each permanent magnet 62. Subsequently, the action of the slit portion 614 provided in the rotor yoke 61 and that of the gap portion 612 formed between the rotor yoke 61 and the permanent magnet 62 will be explained with reference to Figs. 8 and 9. Fig. 8 is a view illustrating the magnetic flux density distribution at the time when having caused the starter / generator device 1 to function as a starter motor, while Fig. 9 is a view illustrating the magnetic flux density distribution at the time when having caused this device 1 to function as a generator. When causing the starter / generator device 1, functioning both as a starter and as a generator, to function as the starter motor, supplying an excitation current from the battery 42 to each stator winding 53 via the control unit 40 is accompanied by the following action. Namely, as illustrated in Fig. 8, a line of magnetic force that has generated from a stator salient pole 52N, which has been excited to have an N pole, in the radial direction goes through the stator-side obverse surface of the S-pole permanent magnet 62S to the reverse surface thereof. Then most part of it passes through the core portion 615 of the rotor yoke 61 and the interpole 613 thereof and then through the stator salient pole 52S that is adjacent to the stator salient pole 52N and that has been excited to an S pole. It then passes through the stator core 51 to return to the stator salient pole 52N that has been excited to the N pole. At this time, the gap portions 612 are formed at the both side portions that are existent in the peripheral direction of each permanent magnet 62, so the leak magnetic flux from the side portion of each permanent magnet 62 into the interpole 613 is decreased. Therefore, most of the lines of magnetic force go from each permanent magnet 62 into the core portion 615 of the rotor yoke 61, and further, go through the interpole 613 and reaches the stator 50 side. As a consequence, the vertical components of the magnetic flux passing through the air gaps between the outer rotor 60 and the stator 50 increase, and therefore the drive torque can be more increased than in the case having no gap portions 612 provided. Furthermore, in this embodiment, since as the stator side as well on both side portions of the permanent magnet 62 there are formed the slits 614 for limiting the magnetic path existent in the peripheral direction, the leak magnetic flux passing through the inner side of the rotor yoke 61 is also decreased. As has illustrated in Fig. 10 on an enlarged scale the interior of a circle indicated in a broken line in Fig. 8, one (614A) of the slits 614 obstructs the entry into the inner-side peripheral portions 616 of the rotor yoke 61, of the magnetic flux Bl passing through the interpole 613 of the rotor yoke 61. That slit 614 thereby so acts as to highly efficiently guide more of the magnetic flux Bl to the stator salient pole 52S. The other (614B) of the slits 614 obstructs the entry into the interpoles 613, of the magnetic flux B2 passing from the permanent magnet 62N through the inner-side peripheral portion 616 of the rotor yoke 61. That slit 614B thereby so acts as to highly efficiently guide more of the magnetic flux B2 to the stator salient pole 52S. In consequence, the vertical components of the magnetic flux passing through the air gaps between the outer rotor 60 and the stator 50 further increase. Resultantly, the drive torque as the starter motor can be further increased. When causing the starter / generator device 1 to function as a generator, as illustrated in Fig. 9 the magnetic flux that generates from each permanent magnet 62 forms a closed magnetic circuit together with the stator salient pole and stator core. Therefore, it is possible to generate in the stator winding a generator current corresponding to the number of rotations of the rotor. In this embodiment, the regulation voltage that is to be regulated by a regulator 100 as later described is set to be at the value of 14. 5V. When the output voltage that generates when having caused the starter / generator device 1 to function as the generator reaches that regulation voltage, it is arranged that the phase current be short-circuited. Resultantly, short current flows into each stator winding 53 with the phase of lag. Resultantly, the lines of magnetic force that pass through the stator 50 decrease with the result that the leak magnetic flux that connects adjacent two, to each other, of the permanent magnets 62 increases. Therefore, the driven torque of the starter / generator device 1 decreases. Therefore, the load of the internal combustion engine E decreases. Namely, as has illustrated in Fig. 11 on an enlarged scale a circle indicated by a broken line in Fig. 9, between adjacent permanent magnets 62S and 62N, there generate the following magnetic fluxes. A magnetic flux B3 passing through the outer-side peripheral portion 617 of the rotor yoke 61; amagnetic flux B4 passing through the interpole 613 of the rotor yoke 61; a magnetic flux B5 passing through the inner-side peripheral portion 616 of the rotor yoke 61; and a magnetic flux B6 passing through the inner-side peripheral portion 616 of the rotor yoke 61, air gap, and stator salient pole 52N. According to this embodiment, in the permanent magnet type rotary electric machine wherein the rotor yoke 61 of the outer rotor 60 has the interpole portions 613 between the respective permanent magnets 62, the gaps 612 and slits 614 are provided between the respective permanent magnets 62 and the rotor yoke 61. Therefore, the leak magnetic flux is decreased between each adjacent two of the permanent magnets and the magnetic flux that vertically intersects the air gap portions between the outer rotor 60 and the stator 50 increases . Accordingly, itispossible to increase the drive torque when causing the permanent magnet type rotary electric machine to function as a starter motor without increasing the driven toque when causing it to function as a generator. Fig. 12 is a block diagram of a control system for the combined starter/generator 1, in which the same reference numerals as above represent the same or equivalent portions. In an ECU (electric control unit) are provided a three-phase full wave rectifier 300 for full wave-rectifying a three-phase alternating current produced by the generator function of the combined starter/generator 1 and a regulator 100 which restricts an output of the full wave rectifier 300 to a predetermined regulating voltage (a regulator operating voltage: say 14.5V) . To the ECU are connected a rotor angle sensor 29, an ignition coil 21, a throttle sensor 23, a fuel sensor 24, a seat switch 25, an idle switch 26, a cooling water temperature sensor 27, and an ignition pulser 30, and detection signals are inputted from these portions to the ECU. A spark plug 22 is connected to a secondary side of the ignition coil 21. Further connected to the ECU are a starter relay 34, a starter switch 35, stop switches 36 and 37, a stand-by indicator 38, a fuel indicator 39, a speed sensor 40, an auto-by starter 41, and a headlight 42. A dimmer switch 43 is provided in the headlight 42. An electric current is fed to the above various portions from a battery 46 via a main fuse 44 and a main switch 45. The battery 46 is directly connected to the ECU through the starter relay 34, while it has a circuit for connection to the ECU via the main fuse 44 alone. Next, a method of controlling the excitation for advancing the object angle according to this embodiment will be explained with reference to the waveform diagrams of Figs. 13 to 16. In this embodiment, one full rotation of the rotor is divided into a plurality of stages (#0, #1, #2, ) according to the detection signals from the respective magnetic pole sensors 29U, 29V and 29W, and the respective phase currents are controlled in units of the stage. As illustrated in Fig. 13, in this embodiment, the portion, corresponding to 60° (mechanical angle), of the rotor is set to have an electrical angle of 360", which is divided into six stages (#0 to #5) . Accordingly, one stage corresponds to the mechanical angle of 10°. In the low-rotation range, and at the time of reverse rotation, of the rotor, the excitation for normal rotation (reverse rotation) made through the electrical angle of 120° is executed with the advancement of 5° (mechanical angle) . In the high-rotation range of the rotor, the excitation for normal rotation made through the electrical angle of 180° is executed with the advancement of 10° (mechanical angle). Fig. 14 is a signal waveform diagram illustrating a case where the excitation for normal rotation of the 120° angle is executed with the advancement of the 5° angle. Fig. 15 is a signal waveform diagram illustrating a case where the excitation for the 180°-angle normal rotation is executed with the 10°-angle advancement. Fig. 16 is a signal waveform diagram illustrating a case where the excitation for the 120°-angle reverse rotation is executed with the 5"-angle advancement. In this embodiment, it is arranged that each of the respective magnetic pole sensors 29U, 29V, and 29W detects the change in the magnetic field and that, with the timing at which that detection signal is thereby displaced, the timing at which excitation is made with respect to each corresponding phase be changed over. Saying more concretely, in the case of Fig. 14 where the excitation for normal 120"-angle rotation is executed with the advancement of the 5 ° -angle, the following operation is performed. With the timing at which the detection signal of the V-phase sensor (the magnetic pole sensor 29V) falls, i.e. with the timing at which the stage #0 is changed over to the stage #1, the excitation in the normal direction with respect to the V-phase is started while, at this timing, the excitation in the normal direction with respect to the U-phase is kept stopped. Similarly, with the timing at which the detection signal of the U-phase sensor (the magnetic pole sensor 29U) rises, i.e. with the timing at which the stage #1 is changed over to the stage #2, the excitation in the reverse direction with respect to the U-phase is started while, at this timing, the excitation in the reverse direction with respect to the W-phase is kept stopped. Similarly, with the timing at which the detection signal of the W-phase sensor (the magnetic pole sensor 29W) falls, i.e. with the timing at which the stage #2 is changed over to the stage #3, the excitation in the normal direction with respect to the W-phase is started while, at this timing, the excitation in the normal direction with respect to the V-phase is kept stopped. Similarly, even in the case of the 10°-angle advancement by the normal 180°-rotation excitation illustrated in Fig. 15, with the timing at which the stage #0 is changed over to the stage #1, the excitation in the normal direction with respect to the U-phase is switched to the excitation in the reverse direction. Similarly, with the timing at which the stage #1 is changed over to the stage #2, the excitation in the reverse direction with respect to the W-phase is switched to the excitation in the normal direction. Similarly, with the timing at which the stage #2 is changed over to the stage #3, the excitation in the normal direction with respect to the V-phase is switched to the excitation in the reverse direction. In other words, in this embodiment, the respective magnetic pole sensors 29U, 29v, and 29w are disposed at their prescribed positions so that they may detect the change in the magnetic field with the timing for the angle-advance supply of each phase current and that the output of their detection signal may thereby be varied. In this embodiment, the respective magnetic pole sensors have been disposed at their prescribed positions so that the timing for switching the angle-advance supply of the phase current may coincide with the timing for the displacement of the detection signal from the magnetic pole sensor 29. Therefore, it becomes possible to perform accurate control of the excitation when using the phase current for advancing the angular phase. Further, in this embodiment, since the angle degrees for the advancement of the angular phase have been set to be 5° that is a half of the 10° corresponding to one-stage angular phase. Therefore, even in the case of the 5°-angle advancement by the reverse 120°-rotation excitation, illustrated in Fig. 16, using the same magnetic-pole sensor 29 as in the case of the normal rotation, the following merit is obtained. Namely, it is possible to make the timing for switching the angle advance excitation coincide with the timing for the displacement of the magnetic pole sensor signal. Accordingly, according to this embodiment, not only at the time of normal rotation but also at the time of reverse rotation, it becomes possible to accurately control the excitation when using the phase current for the angle advancement. Industrial Applicability According to the present invention, the following effects are brought about. (1) Since the timing at which the excitation is switched when controlling the angle advancement coincides with the timing at which the change in the magnetic field is detected by the magnetic pole sensor, it becomes possible to accurately control the excitation when controlling the angle advancement. (2) Since the angle degrees for the advancement of the angular We Claim: 1. A brushless polyphase AC generator, the brushless polyphase AC generator including a stator (50) and its winding (53); a cylindrical rotor (60) having a plurality of permanent magnets (62) each disposed in the circumferential direction and rotating relative to the stator; magnetic pole sensors (29) for detecting the rotary position of a rotor, wherein a phase current is supplied to each phase of the windings for angle-advancement according to the detection signal of the magnetic pole sensor, the rotor has an interpole portion (613) between each adjacent two of the permanent magnets, wherein the phase current supplied to each phase is angle advanced though a amount of angle represent a circumferential width of the interpole portion so that the timing with which the phase current is supplied may coincide with the timing with which the magnetic field detected by the magnetic pole sensor is changed. 2. A brushless polyphase AC generator as claimed in claim 1, which is a starter motor that is connected to a crank shaft (201) of an internal combustion engine to thereby crank the internal combustion engine. 3. An excitation control apparatus for the brushless polyphase AC generator as claimed in claim 1 or 2, wherein the excitation control apparatus for the brushless polyphase AC generator has the magnetic pole sensors according to the output signal from each of that one full rotation of the rotor is divided into a plurality of stages, whereby the respective phase currents are controlled in units of the stage, wherein the phase of the phase current supplied to each phase is angle advanced by a half of the angular range corresponding to the one stage. 4. An excitation control apparatus for the brushless polyphase AC generator as claimed in claim 4, wherein between at the time of normal rotation and at the time of reverse rotation the advancing amount of angle is the same. 5. An excitation control apparatus for the brushless polyphase AC generator as claimed in claim 4 or 5, wherein, when the rotation speed of the rotor exceeds a prescribed value of standard speed, the advancing amount of angle is changed over to the angle corresponding to the one-stage phase. 6. An excitation control apparatus for the brushless polyphase AC generator as claimed in any one of claims 4 to 6, wherein, when the rotation speed of the rotor is below the prescribed value of standard speed, excitation for angle advancement of 120 (electrical angle) is made for each phase. 7. An excitation control apparatus for the brushless polyphase AC generator as claimed in any one of claims 4 to 7, wherein, when the rotation speed of the rotor exceeds the prescribed value of standard speed, excitation for angle advancement of 180° (electrical angle) is made for each phase. Dated this 17th day of March, 2003. [RANJNA MEHTA DUTT] OF REMFRY AND SAGAR ATTORNEY FOR THE APPLICANTS

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314-mumnp-2003-claims(granted)-(2-12-2005).doc

314-mumnp-2003-claims(granted)-(2-12-2005).pdf

314-mumnp-2003-correspondence(14-12-2005).pdf

314-mumnp-2003-correspondence(ipo)-(9-12-2005).pdf

314-mumnp-2003-form 19(8-10-2004).pdf

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314-mumnp-2003-form 2(granted)-(2-12-2005).doc

314-mumnp-2003-form 2(granted)-(2-12-2005).pdf

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314-mumnp-2003-form 3(17-3-2003).pdf

314-mumnp-2003-form 3(2-12-2005).pdf

314-mumnp-2003-form 5(17-3-2003).pdf

314-mumnp-2003-form-pct-ipea-409(17-3-2003).pdf

314-mumnp-2003-form-pct-isa-210(17-3-2003).pdf

314-mumnp-2003-petition under rule 137(2-12-2005).pdf

314-mumnp-2003-power of authority(17-9-2003).pdf

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