Three-phase dual-phase electric machine and control method for such machine

Abstract

The present invention relates to an electric machine having a first three-phase winding and a second three-phase winding, the stator being formed of a cylindrical yoke made of a soft ferromagnetic material having a set of radially extending teeth that support a plurality of the windings, the windings being separate from one another, the first three-phase winding being connected in a delta configuration and the second three-phase winding being connected in a star configuration.

Description

Detailed Description of the Invention

[0001] [Field of the Invention] This application relates to the field of polyphase electrical machines and their control. More particularly, this application relates to machines having a plurality of winding systems that need to operate at relatively high ambient temperatures (typically 160°C).

[0002] Preferably, the present invention will find privileged use in demanding automotive applications, such as within an electric camshaft phaser or in an actuator for a wastegate of a turbocharger. In these applications, there is a significant source of heat dissipation nearby, and significant compactness is required for integration into the environment. However, the present invention is not limited to these applications.

[0003] [Prior Art] In the prior art, the following documents are already known, presenting a polyphase electrical architecture (configuration) having two three-phase systems: Document EP3098963 presents, for example, a three-phase dual architecture that minimizes the common mode of a machine when driven in vector control. With vector control, good machine performance regarding torque regularity can be obtained. However, vector control has the drawback that it requires complex control by precise position sensors and advanced control electronics.

[0004] Also, document US2014375232 presents a three-phase dual architecture having two separate power sources with an energy transfer circuit between the two three-phase systems. Again, in this case, the control of the machine is vector control, and moreover, the power supply needs to be doubled.

[0005] Furthermore, document WO2016012703 presents a three-phase dual architecture for automotive applications, having two separate control modules. These two modules are interconnected to minimize their total losses. While the type of control is not specified, a certain phase angle control is required for the two electronic modules. It is also well known that creating a 30° offset between two three-phase systems is necessary to obtain an equivalent to a balanced six-phase architecture.

[0006] Finally, reference EP3224929 presents a three-phase dual architecture using star and delta connections. Two such three-phase networks are coupled to two voltage sources having different values.

[0007] [Issues not resolved by conventional technologies] In the context of automotive applications operating at medium power (typically tens of watts to several kilowatts), conventional architectures are not efficiently and economically applicable. In fact, by employing complex vector control or two separate electronic modules, these solutions become excessively bulky and expensive compared to competing three-phase solutions, the latter being the most common in these applications today.

[0008] Furthermore, existing three-phase dual systems often use electromechanisms with several windings per phase. The mixing of different phases from two three-phase systems, resulting in typically 12 or more windings to handle, makes manufacturing uneconomical and industrially complex.

[0009] Conventional technology lacks a simple and economical solution that would enable the creation of compact actuators for medium-power automotive applications that offer the advantages of a three-phase dual system compared to a simple three-phase system (i.e., larger and more consistent average torque, harmonic components in the signal, and more favorable torque).

[0010] [Purpose of the invention] The main objective of the present invention is to provide a simple and economically feasible three-phase dual electromachine for medium-power applications in the automotive industry.

[0011] In particular, one of the objectives of the present invention is to propose a general connection configuration for a three-phase dual machine optimized for block control, by using separation teeth to magnetically separate multiple phases of each semi-machine and multiple phases between two semi-machines. As a result, the proposed connection configuration is suited to the simplicity of block control compared to vector control according to the prior art.

[0012] One of several other objectives of the present invention is to significantly limit or simplify the number of motor windings, thereby enabling improved compactness compared to equivalent three-phase solutions.

[0013] Furthermore, within the scope of the present invention, particularly in the context of using block switching, a simple control for such a machine is proposed. This control is supported by economical electronic equipment and is far simpler to implement than vector control, while retaining the aforementioned advantages.

[0014] More specifically, the present invention relates to an electric machine comprising a stator formed of a cylindrical yoke made of a soft ferromagnetic material having a set of teeth extending radially, the set of teeth supporting a plurality of windings, the plurality of windings being separate from each other, the first three-phase winding being electrically connected in a delta configuration, and the second three-phase winding being electrically connected in a star configuration, wherein the total number of teeth of the stator is equal to 3(N1+N2)(k+1), where k is a natural number of 1 or more representing the number of consecutive coils of the same phase in the winding, N1 and N2 are the number of groups consisting of consecutive coils of the same phase in the first and second windings, respectively, and the two windings are separated by at least one tooth that does not support any winding.

[0015] In the spirit of this invention, "number of consecutive coils of the same phase" means the number of coils belonging to the same phase and the same semi-machine that are adjacent to each other and not separated by teeth that do not have windings.

[0016] Similarly, in the spirit of the present invention, “number of groups consisting of consecutive coils of the same phase” means the number of groups consisting of consecutive coils belonging to the same phase of the same semi-machine, separated by at least one separating tooth. These groups of coils may be separated by a single separating tooth, or by multiple teeth and other groups consisting of coils belonging to other phases.

[0017] Preferably, the multiple windings are supported by the main teeth, and the teeth that do not support any windings are separating teeth, and the angular width of the separating teeth, defined by the width of the free end of the tooth as viewed from the center of the electric machine, is less than or equal to the angular width of the main teeth. In this way, the magnetic flux collected by the teeth with windings is maximized.

[0018] A preferred machine would have a total of 12 teeth, alternating between teeth with 6 windings and teeth without windings, according to the relationship N1=N2=k=1. As a result, the manufacture of the machine would be economical.

[0019] In one possible embodiment, the first three-phase winding is supported by a first group of continuous stator teeth, each having alternating teeth with and without windings, and the second three-phase winding is supported by a second group of continuous stator teeth, each having alternating teeth with and without windings, and the first group of stator teeth and the second group of stator teeth are separated from each other.

[0020] In another embodiment, the first three-phase winding and the second three-phase winding are arranged alternately to form a periodic pattern consisting of a first tooth of the stator supporting the coil of the first winding, a second tooth of the stator not supporting any winding, and a third tooth of the stator supporting the coil of the second winding, wherein the first, second, and third teeth are continuous in the circumferential direction of the stator.

[0021] Preferably, the first winding is distributed angularly across a first sector of 180°, the second winding is distributed angularly across a second sector of 180°, the first sector and the second sector are isolated from each other, each of the multiple windings is electrically connected to a set of multiple electric tracks, and the multiple sets of multiple electric tracks are isolated from each other and distributed angularly across two isolated 180° angular sectors.

[0022] Furthermore, the present invention relates to a control method for a machine having the above-described three-phase double winding, characterized in that each three-phase winding is controlled by a block sequence, each three-phase winding is controlled in a state where they are electrically offset from each other by 30°, and as a result, 12 electrically uniformly distributed control vectors are generated.

[0023] Preferably, the first winding and the second winding are powered by two different power bridges, each equipped with six electronic switch cells.

[0024] The above block control is performed using pulse width modulation (PWM), where a first PWM is applied to the first winding and a second PWM is applied to the second winding, and the first and second PWMs are applied in such a way that they cancel out or minimize the overlap time during which positive AC is applied simultaneously.

[0025] In one embodiment, the plurality of PWMs are applied to the plurality of electronic switch cells. In a variant embodiment, the electromechanical device further includes a bridge rectifier formed by four electronic switch cells that receive, as an input, a two-wire electrical signal from a central control unit upstream of the plurality of power bridges each having six electronic switch cells. The block control is performed using pulse width modulation, referred to as PWM. The PWM control is applied as an input to the bridge rectifier. The bridge rectifier performs active rectification of the PWM control, and the two power bridges are controlled at full pitch.

[0026] The control of the two three-phase windings can be performed by one and the same microprocessor or by two separate microprocessors.

[0027] Furthermore, the present invention relates to an adjusting device for continuously phase-shifting the rotational angle of a camshaft that controls the gas exchange valves of an internal combustion engine with respect to a drive element, particularly a chain or a belt, the adjusting device comprising a brushless adjusting electric motor having a stator that is stationary with respect to an outer ring gear, the brushless adjusting electric motor being coupled to a reduction gear having three inputs / outputs including the outer ring gear (4), an input element, and an output disk, the outer ring gear being driven by the drive element, and the output disk being fixed to the camshaft, wherein the brushless adjusting electric motor is an electromechanical device according to the above-described plurality of variant forms.

[0028] Furthermore, the present invention relates to a system comprising an electromagnetic actuator for controlling a wastegate of a turbocharger and the wastegate, wherein the motor is an electromechanical device according to the above-described plurality of variant forms. <Preliminary Explanation of the Drawings>[

[0029] ​Other features and advantages of the present invention will become apparent by reading the following detailed embodiments with reference to the accompanying drawings. The accompanying drawings illustrate the following:

[0030] [Figure 1] Figure 1 is a schematic cross-sectional view of the machine according to the present invention in the first embodiment.

[0031] [Figure 2] Figure 2 is a schematic cross-sectional view of the machine according to the present invention in a second embodiment.

[0032] [Figure 3] Figure 3 is a schematic cross-sectional view of the machine according to the present invention in a third embodiment.

[0033] [Figure 4] Figure 4 is a schematic cross-sectional view of the machine according to the present invention in a fourth embodiment.

[0034] [Figure 5] Figure 5 is a schematic cross-sectional view of the machine according to the present invention in the fifth embodiment.

[0035] [Figure 6] Figure 6 is a perspective view of the machine according to the present invention having the electrical connections of the above phases according to the first embodiment.

[0036] [Figure 7] Figure 7 is a perspective view of the machine according to the present invention, having the electrical connections of the above phases according to the second embodiment.

[0037] [Figure 8] Figure 8 is a schematic cross-sectional view of the machine according to the present invention in another embodiment.

[0038] [Figure 9a] [Figure 9b] Figures 9a and 9b are two schematic cross-sectional views of a machine according to the present invention in a particular embodiment.

[0039] [Figure 10] Figure 10 is a schematic diagram of the connection of the machine according to the present invention to a control converter in a first exemplary embodiment.

[0040] [Figure 11] Figure 11 is a schematic diagram of the connection of the machine according to the present invention to a control converter in a second exemplary embodiment.

[0041] [Figure 12] Figure 12 is a timing chart of block control using pulse width modulation, which can be used to control a machine according to the present invention.

[0042] [Figure 13] Figure 13 shows two detailed pulse width modulation timing charts for different duty cycles, and two different methods applicable to machines according to the present invention.

[0043] [Figure 14] Figure 14 is a timing chart of block control using pulse width modulation that can be used for controlling a machine according to the present invention.

[0044] [Figure 15] Figure 15 shows a first embodiment of a mechatronics assembly that implements the machine according to the present invention.

[0045] [Figure 16] Figure 16 shows a second embodiment of a mechatronics assembly that implements the machine according to the present invention.

[0046] [Figure 17] Figure 17 shows a third embodiment of a mechatronics assembly that implements the machine according to the present invention.

[0047] [Figure 18] Figure 18 shows a cross-sectional view of an apparatus according to one embodiment.

[0048] [Figure 19a] [Figure 19b] Figures 19a and 19b are schematic diagrams of the connection of the machine according to the present invention to a control converter, and represent two switching states used to characterize the phases of the first three-phase winding.

[0049] [Figure 20a] Figure 20a shows the voltage measurement results at the two terminals of the three-phase inverter.

[0050] [Figure 20b] Figure 20b shows the measurement results of the current flowing through the current measuring element during one of the coil characteristic evaluation sequences.

[0051] [Figure 21a] Figures 21a and 21b are schematic diagrams of the connection of the machine according to the present invention to a control converter, representing high torque control and its low torque adaptation, with deactivation of one of the two three-phase windings.

[0052] [Detailed description of the embodiment] Figure 1 shows a first embodiment of the electrical machine according to the present invention. This first embodiment comprises a stator (3) composed of two semi-machines ((1) and (2) respectively). Each semi-machine supports three-phase windings (4a, 4b, 4c) and three-phase windings (5a, 5b, 5c). The subscripts a, b, and c represent the phases of the formed three-phase system, respectively. The stator (3) is in the shape of a cylindrical ring (6), from which teeth extend radially. Each semi-machine (1, 2) has two types of teeth arranged alternately with each other: teeth (8) that support coils are called principal teeth. Teeth (7) that do not support any windings are called separator teeth. These teeth (7) have the role of magnetically separating multiple phases and the two semi-machines. The semi-machine (1), composed of all principal teeth (8) and minor teeth (7), forms three basic patterns arranged tangentially and continuously. Furthermore, the semi-mechanical unit (2), composed of all the main teeth (8) and secondary teeth (7), forms three basic patterns arranged tangentially and continuously. In this embodiment of Figure 1, the various phases of the first semi-mechanical unit (1) are connected in a delta configuration, and the various phases of the second semi-mechanical unit (2) are connected in a star configuration. The separating teeth have an opening angle (spreading angle) (a7). The apex of this angle is the rotation center of the motor, and this angle is determined by the width of the teeth at its open end. To maximize the magnetic flux collected by the main teeth (8) and thereby improve the performance of the device, this angle is less than or equal to the opening angle of the main teeth (a8). However, within the scope of the present invention, this relationship is not strictly necessary.

[0053] In Figure 1, the rotor consists of a magnet (9) inside a rotor yoke (10) made of a ferromagnetic material, and a shaft (not shown) which may or may not be ferromagnetic. This rotor is shown as an example only, and any other type of rotor conventionally used in any brushless machine may be used.

[0054] Figure 2 shows a modified embodiment similar to that shown in Figure 1. However, Figure 2 differs from Figure 1 in that the main teeth (8) have flares (29), i.e., magnetic pole pieces, at their open ends in order to collect more magnetic flux generated by the rotor, and the rotor has magnets (9) on the surface of the yoke (10), and the rotor is the rotor according to the second embodiment.

[0055] Figure 3 shows an alternative embodiment of the machine in which the rotor is not visible. In this case, each semi-machine (1, 2) consists of three basic patterns extending across a 60° machine angle. These basic patterns are made up of a set including three consecutive main teeth (8) and a separator tooth (7). Each of the three main teeth supports a set of coils belonging to the same phase of the same semi-machine. In Figure 3, subscripts A, B, and C refer to three different phases of each semi-machine (subscript 1 and subscript 2) separated from each other by separator teeth (7) that do not support any windings. In this case, the two semi-machines (1) and (2) are overlapping (nested). This is because the phase of the second semi-machine (subscript 2) follows the phase of the first semi-machine (subscript 1) in the angular direction, and these two are separated by the separator tooth (7).

[0056] Figure 4 shows a modified embodiment similar to the modified embodiment in Figure 3. However, each of the two semi-machines (1) and (2) is spatially located across 180°, and the first semi-machine (subscript 1), like the second semi-machine (subscript 2), is composed of three basic patterns that are continuous in the tangential direction. Each phase (A_2, B_2, C_2, A_1, B_1, C_1) is supported by three main teeth (8) and separated by separating teeth (7).

[0057] Figure 5 shows a 36-tooth machine with four coils per phase. Each phase has two groups of two teeth. The two teeth in the two groups face each other in diameter. Two semi-machines (subscript 1 and subscript 2) are superimposed; that is, two teeth with windings belonging to the same phase in the same machine are arranged alternately with two teeth with windings belonging to the same phase in the other machine. Each group of two teeth is separated from the adjacent group of two teeth by a separating tooth (7).

[0058] Figure 6 shows a connection component of a device having six main teeth (8) and six separator teeth (7) as a non-limiting embodiment. The stator (3) is made of two semi-mechanical units (1) and (2), each extending over an angle of approximately 180°. This solution ensures the connection of multiple windings by distributing current between the two semi-mechanical units. Two sets of conductive components (11) and (12) (usually made of copper) ensure the electrical connection of the windings of the first semi-mechanical unit (1) in a star configuration and the connection of the windings of the second semi-mechanical unit (2) in a delta configuration. To improve the compactness of the assembly and reduce the risk of electrical contact between various electrical components without the use of specific insulation, the sets of conductive components (11) and (12) may, advantageously, be placed on the same plane.

[0059] Figure 7 shows an alternative configuration for connecting two semi-mechanical windings by directly connecting to the various windings using a printed circuit (13) without using the aforementioned conductive components. The tracks on the printed circuit (13) perform the star and delta connection functions of the windings. In this solution, each coil is directly connected to the printed circuit (13) by press-fit connections.

[0060] Figure 8 shows an electromachine according to an alternative embodiment, which has a rotor outside the stator and a yoke (10) supporting a ring of magnets (9). The semi-machines are stacked. The coils (4A, 4B, and 4C) belong to the first semi-machine, and the coils (5A, 5B, and 5C) belong to the second semi-machine. A special feature is that the pole pieces (29) have an extended free end on the main teeth (8) that faces the rotor. The separating teeth have a constant width in the radial direction and are not extended at their free ends.

[0061] Figures 9a and 9b show another embodiment in which two semi-machines (1, 2) are each configured on a semi-stator (1a, 1b). Figure 9a is a pre-assembly diagram, and Figure 9b is a post-assembly diagram. The boundary between the two semi-stators (3a, 3b) may be in the center of the separator teeth (7), or, as shown, on the edge of the separator teeth (7). In this embodiment, by mounting the coils (4, 5) of the two semi-machines before the machine is fully assembled, it is possible to insert longer coils (4, 5) onto the main teeth (8) than in other embodiments. The assembly of various coils (4, 5) would not have been possible on a single stator. These coils cannot pass through the central opening where the rotor (not shown) needs to be housed.

[0062] Figure 10 shows a schematic diagram of the electrical connection of the machine according to the present invention to the converter. Each semi-machine, connected in a star (1) configuration and a delta (2) configuration, is supplied with voltage by a three-phase bridge (14, 15), each of which consists of six electronic switches. This is a standard configuration for those skilled in the art. The converter has a filter (16) as its input. The filter (16) is connected to a voltage source (E) and consists of a set of inductors (17) and a capacitor bank (18). This filter (16) is connected to the terminals of the three-phase bridge (14, 15) connected to the two semi-machines (1, 2). Adaptive and alternating control of various switches makes it possible to minimize the size of the filter (16). This reduces cost and overall size.

[0063] Figure 11 shows a schematic diagram of the electrical connection of the machine according to the present invention to the converter. This electrical connection enables control of the six-phase machine via two-wire pulse control (30), such as that supplied by an electronic control unit (ECU) of a vehicle powered by a voltage source such as a battery (E), via pulse width modulation known as PWM. Since the two-wire signal (30) can have negative or positive polarity, i.e., the electrical ground can be on the upper or lower line, the converter includes an active rectifier (19) controlled by four electronic switches. This makes it possible to pass the positive or negative pulse signal through to a positive pulse and supply the positive pulse to a three-phase bridge (14, 15).

[0064] Figure 12 illustrates the control principle applied to the phases of two semi-machines. Commands C1 and C2 are applied to the branching of the three-phase bridge in Figure 10. For example, command C2 has an electrical offset of 30° relative to command C1. This angular offset stems from the electrical offset of the induced voltages of multiple phases of the second semi-machine compared to those of the first semi-machine. Each command C1 and C2 consists of control of voltage-side transistors called the "high side" (HS1, HS2), which receive PWM-type chopped voltages (PWM1, PWM2), and control of ground-side transistors called the "low side" (LS1, LS2), which receive a constant voltage (ON). Each control shown in this figure has traditionally been used as a block for three-phase machines and is also called "slow decay". Figure 13 illustrates two methods for controlling the semi-machines, labeled P1 and P2, respectively, using pulse-width modulated commands PWM1 and PWM2 applied to the three-phase bridge of each semi-machine. The objective of the two methods P1 and P2 is to reduce current ripple and, as a result, minimize the recovery time during which the two semi-machines are supplied simultaneously, thereby minimizing the size of the aforementioned filters for the converters driving the machines. This objective can be achieved by alternating the power supply of the two semi-machines as much as possible, according to the duty cycle shown as a percentage in the figure. This method will be even more effective when the duty cycle is low. As shown in Figure 13, for either method P1 or P2, no overlap is observed between PWM1 and PWM2 when the duty cycle is less than 50%.

[0065] For example, the method for P1 is based on achieving control symmetry with respect to the center of the period. For example, the method for P2 is based on triggering command PWM2 after the completion of positive command PWM1 when the duty cycle is less than 50%, thereby minimizing signal overlap above this value.

[0066] Figure 14 shows a typical signal applied to a converter as shown in Figure 12. DIR1 and DIR2 represent two-wire signals (30). In the case of CAS1 on the left side of the figure, PWM control is generated on the DIR1 line, so a positive average voltage value is obtained on this line. On the other hand, the DIR2 line is zero, corresponding to the electrical ground. In the case of CAS2 on the right side, DIR2 represents a positive average value, and DIR1 is zero. After being rectified by element (19), the signal entering the power bridge (14, 15) will be as shown on line V. However, the control of the switches (HS1, LSI, HS2, LS2) of the power bridge (14, 15) will be performed according to the polarity of DIR1 and DIR2, and will differ in both the case of CAS1 and CAS2.

[0067] Figure 15 shows a mechatronics assembly that enables motion to be generated by using the energy of a vehicle battery (31) that supplies a constant voltage. The vehicle battery (31) is connected to two three-phase bridges (14, 15) after filtering (16). This makes it possible to generate an AC voltage at the terminals of a six-phase machine (20). The six-phase machine (20) is directly connected to a mechanical load (21). The three-phase bridges (14, 15) are controlled by a microcontroller (22). The microcontroller (22) is connected to a central computing unit (ECU). The controller (22) exchanges information with the central processing unit (ECU) via a two-way link (24) and receives information from position sensors (25, 26) and an absolute position sensor (27) at the load output. The position sensors (25, 26) allow the engine position to be determined. Connection to the battery (19) is made via a connector (28). The connector (28) can transfer orders from the computing unit (ECU) and power lines coming from the battery (31).

[0068] Figure 16 shows an alternative embodiment of a mechatronics assembly similar to that in Figure 15, except that two controllers (23a, 23b) are used instead of just one. Each of these controllers (23a, 23b) drives its respective three-phase bridge (14, 15) based on position information from position sensors (25, 26) of the rotor of the machine (20).

[0069] Figure 17 shows a specific embodiment of a mechatronics assembly using the machine according to the present invention, with the converter shown in Figure 11 implemented. In this configuration, a battery (31) powers an electronic control unit (ECU). The ECU supplies a two-wire signal (30) through a connector (28), preferably in PWM signal format. To drive and control the six-phase machine, the two-wire signal (30) passes through a rectifier (19) before being supplied to a three-phase bridge (14, 15) and a microcontroller (23).

[0070] [Application: Electrical phase shifter] The electromechanism according to the present invention is particularly suitable for driving a camshaft phase shifter.

[0071] Figure 18 shows a cross-sectional view of a device according to one embodiment, connected to a camshaft (41). This device consists of an electromechanical unit (42) as described above, coupled to a reduction gear (43). In this case, the reduction gear (43) is of the trochoidal type.

[0072] The reduction gear (43) comprises an outer ring gear (44) driven by a chain or timing belt (not shown) of the internal combustion engine. This outer ring gear (44) has a typical outer diameter of 100 to 150 millimeters and has external teeth suitable for being driven by the timing chain described above. The outer ring gear (44) has a tubular toothed track (45) on its inner surface. This outer ring gear (44) rotates freely relative to the camshaft (41).

[0073] The eccentric gear has a smaller section than the inner section of the outer ring gear (44). The number of teeth of the gear is less than the number of teeth of the toothed track (45) on the inner surface of the outer ring gear (44), and it has the same module.

[0074] To maximize the reduction ratio of the trochoidal reduction gear (43), it is advantageous for the difference between the number of teeth on the eccentric gear and the number of teeth on the toothed track on the inner surface of the outer ring gear to be 1.

[0075] The eccentric gear is guided by bearings mounted on a single shaft (48), and the eccentric axis of rotation is offset relative to the central axis of the single shaft (48). The offset between these two axes is generally 0.1 to 1 mm and depends on the module of the teeth of the trochoidal mesh.

[0076] Furthermore, the output disc (49) is fixed to the camshaft (41) by a screw (50). The output disc (49) is connected by the screw (50) via a radially expanding portion (15) near the axis of rotation of the formed assembly.

[0077] The present invention is not limited to trochoidal reduction gears. In fact, other reduction gears, such as epicyclic reduction gears, may be used. The selection of one or another reduction gear may be determined according to the desired reduction ratio and the final cost of the solution.

[0078] Various details of the manufacture of such a camshaft phase shifter are described in European Patent EP3464841. However, this does not constitute a limitation of protection, but rather constitutes a simple example of an electromechanically driven mechanism according to the present invention.

[0079] [Application: Actuator for wastegates in turbochargers] The electromechanism according to the present invention is particularly suitable for controlling the discharge valve of a turbocharger of an internal combustion engine, commonly referred to as a "wastegate." This wastegate regulates the gas pressure within the turbocharger turbine.

[0080] Heat engines (for automobiles, trucks, construction machinery, etc.) operate by the explosion of a fuel-air mixture in the combustion chamber of a cylinder.

[0081] The engine air loop has the function of guiding, managing, and releasing the air supplied to the engine, and operates using various valves. To improve the performance of the internal combustion engine, some vehicles are fitted with a turbocharger, which is responsible for supercharging the combustion chamber with air.

[0082] The electromechanical device according to the present invention is a particularly suitable solution for applications such as turbochargers that have such demanding requirements.

[0083] [Application: electronic phase balancing method] The electrical machinery according to the present invention inherently possesses sensitivity to imbalances in the impedance or inductance of its phases. These imbalances are common but often negligible in ordinary machinery. These imbalances can arise from manufacturing variations in the number of turns constituting the coil, variations in the quality of electrical connections due to press-fitting or welding, and imbalances in the length of electrical connections. In a specific case of the electrical machinery according to the present invention, the difference in connection configurations of two semi-machines, one connected in a star configuration and the other in a delta configuration, inevitably involves using different numbers of turns between the coils of these two semi-machines in order to obtain equal current at the same inverter voltage. This difference corresponds to the ideal ratio, and the effective number of turns of each of the two semi-machines is obtained by rounding to the nearest integer. This means that errors greater than the impedance of a half-turn can occur. This error becomes more pronounced as the number of turns constituting the winding decreases. As a result, current imbalances occur between multiple phases of the two semi-machines, with an upper limit of 10%. This imbalance leads to premature wear of electronic components, premature wear of the guide system, and torque ripple, which complicates control, as one of the two semi-machines experiences greater stress than the other.

[0084] Figures 19a, 19b, 20a, and 20b propose an economical characterization and compensation method. This method requires the addition of at least one current measuring element (100) to one of the DC lines between the inverter and the filter, as can be seen in Figures 19a and 19b. This at least one current measuring element (100) is placed between the inverter and the filter and is linked to an algorithm that enables identification of the composition of each inverter / motor assembly. The use of this at least one current measuring element (100) allows for optimization of the electrical configuration (architecture). Note that to improve the accuracy of this measurement, multiple current measuring elements (100), for example, one per inverter, can be used.

[0085] Thus, the characteristic evaluation of the impedance and inductance of each phase of a motor at the output of a manufacturing line can be performed using a simple control sequence and the current analysis described above. As shown in Figure 19a, this sequence is based on applying a battery voltage to the phase terminals of a semi-mechanical unit (1) with star-configured windings for a sufficiently long time to analyze the transient current regime due to the inductive effect, and then applying the reverse voltage to the same phase for a sufficiently long time to observe new current fluctuations, as shown in Figure 19b. The voltage is measured at the terminals of the powered phase terminations (101, 102) and typically has the shape given in Figure 20a. The current is measured using a current measuring element (100) and is given in Figure 20b. By measuring the time constant and the amplitude of the current, it is possible to derive the impedance and inductance values ​​of the phases. By repeating this measurement for all phases of the two semi-mechanical units, the ratio of each phase to the phase with the worst characteristics can be calculated. Next, this ratio is used to individually weight the duty cycles of pulse-width modulation that control the voltage waveform supplied to the semi-machine.

[0086] [Application: Electronic method for torque control optimization] The electromachine according to the present invention has torque adjustment with constant resolution throughout its entire functional range. This is due to changes in the duty cycle of pulse width modulation that enable phase voltage control. This fact also holds true for conventional electromachines, such as three-phase electromachines. However, in the synchronous application of two rotating systems, it is necessary to have very good resolution to adjust for small load fluctuations, and therefore, it is often necessary to have an accurate torque response of the electromachine. The two rotating systems consist of, but are not limited to, two electrical subassemblies. When load fluctuations are significant and a larger torque response of the electromachine is required, such resolution is not necessary.

[0087] As shown in Figure 21a, the uniqueness of the present invention makes it possible to improve the torque adjustment resolution in the lowest operating range of torque, with the upper limit being half the nominal torque of the assembly. In this figure, T n is the torque during normal operation, γ is the torque constant, n is the number of turns in each coil, and V DC Rφ is the inverter supply voltage, D is the duty cycle of the transistors that make up the inverter, and Rφ eq and Lφ eq These are the equivalent resistance and equivalent inductance of the coils for two semi-machines with different duty cycles, connected in star and delta configurations. According to the following equation, the minimum possible variation of the torque during normal operation can be determined depending on the minimum variation ΔD of the duty cycle under voltage control.

[0088]

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[0090] [Figure 1] This is a schematic cross-sectional view of the machine according to the present invention in the first embodiment. [Figure 2] This is a schematic cross-sectional view of the machine according to the present invention in a second embodiment. [Figure 3] This is a schematic cross-sectional view of the machine according to the present invention in a third embodiment. [Figure 4] This is a schematic cross-sectional view of the machine according to the present invention in a fourth embodiment. [Figure 5] This is a schematic cross-sectional view of the machine according to the present invention in the fifth embodiment. [Figure 6] This is a perspective view of a machine according to the present invention having the above-mentioned electrical connections of the phases according to the first embodiment. [Figure 7] This is a perspective view of a machine according to the present invention having the above-mentioned electrical connections of the phases according to a second embodiment. [Figure 8] This is a schematic cross-sectional view of the machine according to the present invention in another embodiment. [Figure 9a] These are two schematic cross-sectional views of the machine according to the present invention in a particular embodiment. [Figure 9b] These are two schematic cross-sectional views of the machine according to the present invention in a particular embodiment. [Figure 10] This is a schematic diagram of the connection of the machine according to the present invention to a control converter in a first exemplary embodiment. [Figure 11]This is a schematic diagram of the connection of the machine according to the present invention to a control converter in a second exemplary embodiment. [Figure 12] This is a timing chart for block control using pulse width modulation, which can be used for controlling a machine according to the present invention. [Figure 13] Two detailed pulse width modulation timing charts for different duty cycles, and two different methods applicable to machines according to the present invention. [Figure 14] This is a timing chart for block control using pulse width modulation, which can be used for controlling a machine according to the present invention. [Figure 15] This is a first embodiment of a mechatronics assembly for implementing the machine according to the present invention. [Figure 16] This is a second embodiment of a mechatronics assembly for implementing the machine according to the present invention. [Figure 17] This is a third embodiment of a mechatronics assembly for implementing the machine according to the present invention. [Figure 18] A cross-sectional view of an apparatus according to one embodiment is shown. [Figure 19a] This is a schematic diagram of the connection of the machine according to the present invention to a control converter, and shows two switching states used to characterize the phases of the first three-phase winding. [Figure 19b] This is a schematic diagram of the connection of the machine according to the present invention to a control converter, and shows two switching states used to characterize the phases of the first three-phase winding. [Figure 20a] This shows the voltage measurement results at the two terminals of a three-phase inverter. [Figure 20b] This is the measurement result of the current flowing through the current measuring element during one of the characteristic evaluation sequences of the coil. [Figure 21a] This is a schematic diagram of the connection of the machine according to the present invention to a control converter, illustrating high-torque control and low-torque adaptation, which involves deactivation of one of the two three-phase windings. [Figure 21b]This is a schematic diagram of the connection of the machine according to the present invention to a control converter, illustrating high-torque control and low-torque adaptation, which involves deactivation of one of the two three-phase windings.

Claims

1. It has a first three-phase winding (4a, 4b, 4c) and a second three-phase winding (5a, 5b, 5c), The system comprises a stator (3) formed from a cylindrical yoke (10) made of a soft ferromagnetic material with a pair of teeth (7, 8) extending radially, The set of teeth (8) supports the multiple windings, The multiple windings (4a, 4b, 4c, 5a, 5b, 5c) are distinct from each other. The first three-phase windings (4a, 4b, 4c) are electrically connected in a delta configuration. In an electrical machine where the second three-phase windings (5a, 5b, 5c) are electrically connected in a star configuration, The total number of teeth (7, 8) of the stator (3) is equal to 3(N1+N2)(k+1), k is a natural number greater than or equal to 1 that represents the number of consecutive coils of the same phase in the winding. N1 and N2 are the number of groups consisting of consecutive coils of the same phase in the first winding and the second winding, respectively. An electromachine in which the two windings are separated by at least one tooth (7) that does not support any of the windings.

2. The multiple windings are supported by the main teeth (8), The tooth that does not support any winding is a separation tooth (7), The electric machine according to claim 1, wherein the angular width of the separating tooth (7), defined by the width of the free end of the tooth as viewed from the center of the electric machine, is less than or equal to the angular width of the main tooth (8).

3. N1 = N2 = k = 1, The electric machine according to claim 1, wherein the stator (3) has a total of 12 teeth (7, 8), with teeth having 6 windings and teeth not having 6 windings alternating.

4. The first three-phase winding is supported by a first group of continuous stator teeth, in which teeth with windings and teeth without windings are arranged alternately. The second three-phase winding is supported by a second group of continuous stator teeth, in which teeth with windings and teeth without windings are arranged alternately. The electromachine according to any one of claims 1 to 3, wherein the first group of stator teeth and the second group of stator teeth are separated from each other.

5. The first three-phase winding and the second three-phase winding are arranged alternately to form a periodic pattern consisting of the first teeth of the stator supporting the coil of the first winding, the second teeth of the stator not supporting any winding, and the third teeth of the stator supporting the coil of the second winding. The electric machine according to any one of claims 1 to 3, wherein the first tooth, the second tooth, and the third tooth are continuous in the circumferential direction of the stator.

6. The first winding is distributed angularly across a first sector of 180°, The second winding is distributed angularly across a second sector of 180°, The first sector and the second sector are separated from each other. Each of the multiple windings is electrically connected to a set of multiple electric tracks, The electromachine according to claim 4, wherein the plurality of sets of the plurality of electric tracks are separated from each other and distributed angularly across two separated 180° angular sectors.

7. Each three-phase winding is controlled by a block sequence. A control method for a machine having a three-phase double winding according to any one of claims 1 to 6, wherein each three-phase winding is controlled in a state where it is electrically offset from one another by 30°.

8. A control method for a machine having a three-phase double winding according to claim 6, wherein the first winding and the second winding are powered by two different power bridges (14, 15) each having six electronic switch cells.

9. The aforementioned block control is performed using pulse width modulation, known as PWM. The first PWM is applied to the first winding, The second PWM is applied to the second winding, A method for controlling a machine having a three-phase double winding according to claim 8, wherein the first PWM and the second PWM are applied to cancel out or minimize the overlap time during which positive alternating current is applied simultaneously.

10. A control method for a machine having a three-phase double winding according to claim 9, wherein the plurality of PWMs are applied to the plurality of electronic switch cells.

11. The electric machine further comprises a bridge rectifier formed by four electronic switch cells that receive a two-wire electrical signal coming from a central control unit as input, upstream of a plurality of power bridges having six electronic switch cells, The aforementioned block control is performed using pulse width modulation, known as PWM. The PWM control is applied as the input to the bridge rectifier. The bridge rectifier performs the PWM-controlled active rectification, A control method for a machine having a three-phase double winding according to claim 8, wherein the two power bridges are controlled at full pitch.

12. A method for controlling a machine having a three-phase double winding according to any one of claims 7 to 11, wherein the control of the two three-phase windings is performed by a single, identical microprocessor.

13. A method for controlling a machine having a three-phase double winding according to any one of claims 7 to 11, wherein the control of the two three-phase windings is performed by two separate microprocessors.

14. An adjustment device for a continuous phase shift of the rotation angle of a camshaft that controls a gas exchange valve of an internal combustion engine, relative to a drive element, particularly a chain or belt, It features a brushless adjustable electric motor with a stator stationary relative to the outer ring gear, The brushless adjustable electric motor is coupled to a reduction gear (43) having three inputs / outputs, including the outer ring gear (44), input element (46), and output disk. The outer ring gear (44) is driven by the drive element, The output disk is an adjustment device fixed to the camshaft (41), The brushless adjustable electric motor is an electric machine according to any one of claims 1 to 6, in the adjustment device.

15. In a system comprising an electromagnetic actuator for controlling a turbocharger wastegate and a wastegate, The electromagnetic actuator is an electromachine according to any one of claims 1 to 6, in a system.

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