Multi-system rotation sensor and electric power steering device equipped with the same

Abstract

In order to solve the technical problem of the deterioration of angle detection accuracy caused by the noise voltage generated by the rotor shape offset or eccentricity corresponding to the number of magnetic poles of the rotor core (6) of the multi-system rotary sensor, the number of magnetic poles S of the stator core (4) and the number of magnetic poles R of the rotor core (6) and the number of stator winding systems N (N is a natural number greater than 2) have the relationship S = nRN (n is a natural number). In the S magnetic poles of the stator core (4), each system winding is divided and wound with R magnetic poles. The winding configuration of each system winding (16) is configured to be R times rotationally symmetrical with respect to the rotation axis of the rotor.

Description

Technical Field

[0001] This application relates to a multi-system rotation sensor and an electric power steering device equipped with the multi-system rotation sensor. Background Technology

[0002] Previously, a winding structure was known (for example, see Patent Document 1), which is a multi-system rotary sensor including a stator having a plurality of magnetic poles protruding inward at equal intervals and stator windings wound around each magnetic pole. The stator windings, which consist of a first system winding and a second system winding, are configured such that each system winding is wound alternately at every 1 magnetic pole or every 2 magnetic poles.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2013-247828 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] In this type of multi-system rotary sensor, the stator windings are wound alternately according to a predetermined number of poles, independent of the rotor's pole number. However, in cases of manufacturing deviations or eccentricities in the rotor shape, noise voltages at the rotational frequency are generated in each system winding. Therefore, this winding configuration suffers from a problem where angle detection accuracy deteriorates due to the generated noise voltages.

[0008] This application discloses a technique for solving the above-mentioned problems, the purpose of which is to provide a multi-system rotary sensor with a winding configuration that improves angle detection accuracy.

[0009] Technical means for solving technical problems

[0010] The multi-system rotary sensor disclosed in this application

[0011] The system includes a stator core with S magnetic poles arranged at equal intervals, a stator winding wound around the magnetic poles, and a rotor core with R magnetic poles arranged opposite to the stator core. The stator winding is composed of system windings with a system number N (N is a natural number greater than 2). In this multi-system rotary sensor, the stator winding is composed of an excitation winding and a two-phase output winding. The number of magnetic poles S of the stator core and the number of magnetic poles R of the rotor core and the number of system windings N of the stator winding have the relationship S = nRN (n is a natural number). In the S magnetic poles of the stator core, each system winding is divided and wound with every R magnetic poles. The winding configuration of each system winding is configured to be R times rotationally symmetrical with respect to the rotation axis of the rotor.

[0012] Invention Effects

[0013] According to the multi-system rotation sensor disclosed in this application, each system winding of the stator winding is configured to correspond to the number of magnetic poles R of the rotor core. Therefore, the phase of the noise voltage caused by manufacturing deviations or eccentricity of the rotor shape is 360 / R° between the stator magnetic poles wound in each system winding, thus suppressing the noise voltage generated by each system winding and improving the angle detection accuracy. Attached Figure Description

[0014] Figure 1 This is a structural diagram of a motor system using the multi-system rotary sensor described in Embodiment 1.

[0015] Figure 2 This is a diagram showing the circuit structure of the multi-system rotary sensor according to Embodiment 1 when two system windings are implemented.

[0016] Figure 3 This is a diagram showing the structure of the rotor core and stator core of the multi-system rotary sensor according to Embodiment 1.

[0017] Figure 4 This is a graph showing the relationship between the number of rotor poles and the number of stator poles of the multi-system rotary sensor with two system windings according to Embodiment 1.

[0018] Figure 5 This is a diagram showing the configuration of the system windings wound on the stator poles according to embodiments 1 and 2.

[0019] Figure 6 This is another diagram showing the configuration of the system windings wound on the stator poles according to Embodiment 1.

[0020] Figure 7 This is another diagram showing the configuration of the system windings wound on the stator poles according to Embodiment 1.

[0021] Figure 8 This is a diagram showing an example of the wiring of the system windings of the multi-system rotary sensor according to Embodiment 1.

[0022] Figure 9 It is a diagram showing the complex vectors of the noise voltages induced on the first system winding according to Embodiment 1.

[0023] Figure 10 This is a structural diagram of the multi-system rotary sensor using an external rotor core according to Embodiment 3.

[0024] Figure 11 This is a diagram showing an example of the wiring of each system winding of the multi-system rotary sensor according to Embodiment 4.

[0025] Figure 12 This is another diagram showing an example of the wiring of the windings of each system of the multi-system rotary sensor involved in Embodiment 4.

[0026] Figure 13 This is a diagram showing the circuit structure of a multi-system rotary sensor with three or more system windings according to Embodiment 5.

[0027] Figure 14 This is a graph showing the relationship between the number of rotor poles and the number of stator poles of the multi-system rotary sensor with three system windings implemented in Embodiment 5.

[0028] Figure 15 This is a diagram showing the configuration of the system windings of the three systems involved in Embodiment 5 wound on the stator poles.

[0029] Figure 16 This is another diagram showing the configuration of the system windings wound on the stator poles of the three systems involved in Embodiment 5.

[0030] Figure 17 This is a diagram showing the configuration of the system windings of the dual system according to Embodiment 6 wound on the stator poles.

[0031] Figure 18 This is a diagram showing the structure of the electric power steering device according to Embodiment 7.

[0032] Figure 19 This is a diagram illustrating an example of the hardware structure of the angle calculation unit, excitation circuit unit, and ECU involved in embodiments 1 and 7. Detailed Implementation

[0033] Hereinafter, preferred embodiments of the multi-system rotary sensor involved in this application will be described with reference to the accompanying drawings. Furthermore, detailed descriptions of identical content and corresponding parts will be omitted. Similarly, in subsequent embodiments, structures with the same reference numerals will not be repeatedly described.

[0034] Implementation method 1.

[0035] <Regarding the structure of a dual-system cascade>

[0036] use Figure 1 This embodiment describes the structure of a motor system using a multi-system rotation sensor. Figure 1This is a structural diagram showing an electric motor system 100 using a multi-system rotation sensor. The electric motor system 100 consists of a rotary motor 2, a shaft 3, and a multi-system rotation sensor 8. The rotary motor 2, for example, represents an electric motor installed in an automobile. The rotary motor 2 and the multi-system rotation sensor 8 are connected via the shaft 3. The multi-system rotation sensor 8, connected to the shaft 3, consists of a rotor core 6 forming a rotatable rotor with the shaft 3 as its rotation axis, a stator core 4 opposite to the rotor core 6, a stator winding 5 wound around the stator core 4, an excitation circuit section 1 connected to the stator winding 5, and an angle calculation section 7.

[0037] use Figure 2 Explain the circuit structure of the multi-system rotation sensor 8. Figure 2 This is a circuit diagram of a multi-system rotary sensor 8 that implements a dual-system system winding. Figure 1 The stator winding 5 of the multi-system rotary sensor 8 shown is in Figure 2 The winding consists of a dual system consisting of a first system winding 9 and a second system winding 13. Each system winding 16 is composed of a first output winding 10, a second output winding 11, and an excitation winding 12.

[0038] The first output winding 10 and the second output winding 11 are connected to the angle calculation unit 7, and the excitation winding 12 of each system is connected to the excitation circuit unit 1. The angle calculation unit 7 and the excitation circuit unit 1 can be separate for each system, or they can be connected to one excitation circuit unit 1 and angle calculation unit 7 in multiple systems.

[0039] Next, use Figure 3 The structure of the rotor core 6 and stator core 4 of the multi-system rotary sensor 8 is explained. Figure 3 This is a structural diagram of the rotor core 6 and stator core 4 in a multi-system rotary sensor 8 with a dual-system system winding 16. The rotor core 6 is located on the inner diameter side relative to the stator core 4. The rotor core 6 has a plurality of convex rotor poles 24 that are equally spaced in the circumferential direction and have varying outer diameters. Furthermore, the stator core 4 has a plurality of stator poles 21 that protrude inwardly at equal intervals in the circumferential direction. The rotor poles 24 and stator poles 21 are arranged opposite to each other.

[0040] A shaft 3, serving as a rotation axis, is connected to the inner diameter portion of the rotor core 6. Here, the rotor core 6 and shaft 3 can also be integrated. The system winding 16 is wound around the stator poles 21. Here, one system winding 16 is wound around each stator pole 21. Furthermore, the winding order of the excitation winding 12, the first output winding 10, and the second output winding 11 constituting the system winding 16 can be any one of them.

[0041] Next, use Figures 4 to 7This section explains the relationship between the rotor magnetic pole 24 and the stator magnetic pole 21, which are formed by the system winding 16 of the dual system, and provides an example of the configuration of the system windings 9 and 13 of the dual system. Figure 4 This illustrates an example of the combination of rotor and stator pole numbers in a multi-system rotary sensor 8 with dual-system windings 9 and 13. If we assume the number of systems in system winding 16 is N = 2, the number of rotor poles in rotor core 6 is R, and n is a natural number, then stator core 4 has the stator pole number S as shown in the following formula. Here, Figure 4 The combination shown is an example; any combination that satisfies formula (1) is acceptable.

[0042] [Mathematical formula 1]

[0043] S=nRN (1)

[0044] exist Figure 5 The diagram shows an example of the configuration of the system windings wound around the stator poles with R=4, N=2, n=2, and S=16. The stator poles 21 wound by each system winding 9 and 13 are positioned such that they are rotationally symmetrical about four times in the circumferential direction with respect to the rotor's axis of rotation.

[0045] Therefore, the number of stator poles wound by each system winding 9 and 13 is S / N = 8. In the figure, although each stator pole is marked as A to P, the first system winding 9 is wound on stator poles (A, E, I, M) and stator poles (C, G, K, O), and the second system winding 13 is wound on stator poles (B, F, J, N) and stator poles (D, H, L, P).

[0046] Therefore, windings 9 and 13 of each system can be wound around the magnetic pole in a 4-fold rotationally symmetrical manner; for example, it could also be like this... Figure 6 The first system winding 9 is wound around the stator poles (A, E, I, M) and (B, F, J, N), and the second system winding 13 is wound around the stator poles (C, G, K, O) and (D, H, L, P).

[0047] In addition, Figure 7 With R=4, N=2, n=3, and S=24, the first system winding 9 can be wound around the stator poles (B, H, N, T), (C, I, O, U), and (E, K, Q, W), while the second system winding 13 is wound around the stator poles (D, J, P, V), (F, L, R, X), and (G, M, S, A).

[0048] The system windings 16 of the same system, which are wound on each stator pole 21, are connected in series with each other. Figure 8A wiring example is shown when all windings of the same system are connected in series. In the case of series connection, a structure is considered where the stator poles are connected in series via transition line 30. However, a structure in which a terminal block is used instead of transition line 30 for connection can also be used.

[0049] <Action>

[0050] Next, regarding the operation of this embodiment, firstly, using Figure 3 Explanation follows. The rotor core 6 rotates synchronously with the rotary motor 2. This is achieved by... Figure 1 or Figure 2 The excitation circuit 1 shown applies a voltage to the excitation winding 12 of each system, allowing a preset current to flow and generating magnetic flux inside the rotor core 6 and stator core 4. At this time, due to the rotation of the rotor core 6, the circumferential distribution of its outer diameter changes, thus inducing a sinusoidal voltage with a frequency Rω corresponding to the number of magnetic poles R of the rotor core 6 relative to the rotational frequency ω in the first output winding 10 and the second output winding 11 of each system. The rotor angle is calculated by using the angle calculation unit 7 to calculate the phase of the sinusoidal voltage.

[0051] <Effect>

[0052] Next, regarding the effects of this embodiment, the following will be discussed. Figure 5 The following explanation is provided. As mentioned above, the stator pole positions wound by windings 9 and 13 in each system are configured to be rotationally symmetrical about R = 4 times along the circumferential direction relative to the rotor's axis of rotation. That is, as... Figure 4 As shown, the first system winding 9 is wound around the stator poles (A, E, I, M) and (C, G, K, O), and the second system winding 13 is wound around the stator poles (B, F, J, N) and (D, H, L, P). Furthermore, the rotation of the rotor core 6 changes its outer diameter, thereby inducing sinusoidal voltages in the first output winding 10 and the second output winding 11 of each system.

[0053] When the rotor core 6 is dynamically eccentric, or when the shape of the rotor core 6 changes due to manufacturing deviations, in addition to a sinusoidal voltage with frequency Rω, a noise voltage with rotational frequency ω is induced in the first output winding 10 and the second output winding 11 of each system winding 9 and 13. Taking the stator poles (A, E, I, M) wound by the first system winding as an example, the phase difference of the noise voltage at these stator poles (A, E, I, M) is 360 / R degrees between each pole. Therefore, if the noise voltage is represented in complex vector space, it is as follows: Figure 9 As shown. Here, vectors A1 to A4 represent the noise voltage vectors induced in the stator poles (A, E, I, M), respectively. Here, vector V noiseThis represents the total vector of noise voltages induced in the stator poles (A, E, I, M). The total induced noise voltage V... noise yes Figure 9 Vector V in noise The real part of is therefore represented by the following equation (2), which is almost zero.

[0054] [Mathematical Expression 2]

[0055]

[0056] Where A1 to A4 represent the amplitudes of the noise voltages induced in the stator poles (A, E, I, M), θ0 represents the initial phase of the noise voltage, and ω represents the frequency of the noise voltage.

[0057] Formula (2) also applies to the other stator poles (C, G, K, O), stator poles (B, F, J, N), and stator poles (D, H, L, P) wound in windings 9 and 13 of each system. Therefore, the angle detection error of the multi-system rotary sensor caused by noise voltage can be suppressed, thereby improving the angle detection accuracy. The above effects are not limited to... Figure 5 If the structure shown is a structure in which the system winding 16 is configured in R-fold symmetry along the circumference, that is, the winding configuration of each system winding wound around each magnetic pole of the stator is R-fold rotationally symmetric with respect to the rotation axis of the rotor, then the above effect holds true in all structures.

[0058] Furthermore, as mentioned above, the stator pole positions wound by each system winding can be configured to be R-fold symmetrical along the circumference. Each system winding can be a structure where different systems are configured for every S / RN stator poles. For example, as Figure 6 As shown, the winding configuration can be a first system winding 9 wound around stator poles (A, E, I, M) and stator poles (B, F, J, N), and a second system winding 13 wound around stator poles (C, G, K, O) and stator poles (D, H, L, P). This structure minimizes the length of the transition lines between the poles of each system winding, thereby improving manufacturability.

[0059] Furthermore, each system winding can be configured with a different system winding 16 every other stator pole. For example... Figure 5 As shown, another possible configuration is a winding configuration where the first system winding 9 is wound around the stator poles (A, E, I, M) and (C, G, K, O), and the second system winding 13 is wound around the stator poles (B, F, J, N) and (D, H, L, P). This configuration ensures that the pole configurations of each system winding are distributed as evenly as possible around the entire circumference, thereby improving angle detection accuracy.

[0060] In addition, Figures 5 to 7 In this design, the number of stator poles wound in each system winding 16 is S / N. Therefore, the number of stator poles wound in each system winding is the same, thus ensuring that the angle detection accuracy of each system winding is identical.

[0061] Furthermore, not limited to the winding configurations described above, the same effect can be achieved by freely changing the winding configuration to suit factors such as manufacturability, thereby improving manufacturability.

[0062] Implementation method 2.

[0063] <Regarding the structure of dual-system series connection with the same number of turns>

[0064] In the configuration examples of each system winding 9, 13 described in Embodiment 1, for example... Figure 5 In the first system winding 9, the windings of the same system wound on stator poles with each S / R = 4 are connected with the same number of turns. Specifically, in the first system winding 9, the first output winding 10 and the second output winding 11 with the same number of turns are wound on stator poles (A, E, I, M), and the first output winding 10 and the second output winding 11 with the same number of turns are wound on stator poles (C, G, K, O). Furthermore, in the second system winding 13, the first output winding 10 and the second output winding 11 with the same number of turns are wound on stator poles (B, F, J, N), and the first output winding 10 and the second output winding 11 with the same number of turns are wound on stator poles (D, H, L, P).

[0065] However, for the first system winding 9, the stator poles (A, E, I, M) and stator poles (C, G, K, O) can be wound with different numbers of turns. Similarly, for the second system winding 13, the stator poles (B, F, J, N) and stator poles (D, H, L, P) can be wound with different numbers of turns. Furthermore, the first output winding 10 and the second output winding 11 constituting the first system winding 9 and the second system winding 13 can also be wound with different numbers of turns.

[0066] also, Figure 5 The example shows the case where the number of systems is 2, but it is not limited to this. As long as the number of rotor poles and the number of stator poles satisfy formula (1), the position of the stator poles 21 wound by each system winding 16 can be arranged to be R-fold symmetrical along the circumference. That is, the winding configuration of each system winding wound on each pole of the stator can be R-fold rotationally symmetrical with respect to the rotation axis of the rotor.

[0067] <Effect>

[0068] Next, regarding the effects of this embodiment, the following will be discussed. Figure 5This will be explained. As mentioned above, the windings of the same system wound around each S / R stator pole are wound and connected with the same number of turns. For example, as... Figure 5 As shown, in the first system winding 9, the first output winding 10 and the second output winding 11, with the same number of turns, are wound around the stator poles (A, E, I, M). At this time, if the rotor core 6 is dynamically eccentric, or if the shape of the rotor core 6 changes due to manufacturing deviations, the amplitude of the noise voltage induced in the first output winding 10 and the second output winding 11 of the first system winding 9 is the same in each of the wound stator poles (A, E, I, M), therefore the total induced noise voltage V... noise It is expressed as zero by the following formula (3).

[0069] [Mathematical Expression 3]

[0070]

[0071] Here, A represents the amplitude of the noise voltage induced on each stator pole (A, E, I, M). The above formula (3) also applies to the other stator poles (C, G, K, O), stator poles (B, F, J, N), and stator poles (D, H, L, P) wound in each system winding 16. As a result, the angle detection error caused by the noise voltage generated by rotor shape offset and eccentricity based on the shaft angle can be further suppressed, thereby improving the angle detection accuracy.

[0072] The above effects are not limited to Figure 5 If the rotor magnetic pole number and stator magnetic pole number satisfy formula (1) and the stator magnetic pole position of each system winding 16 is configured to be R-fold symmetrical along the circumference, that is, the winding configuration of each system winding of each magnetic pole of the stator is R-fold rotationally symmetrical with respect to the rotor rotation axis, then the above effects will hold in these structures.

[0073] Implementation method 3.

[0074] <Structure of the external rotor>

[0075] Figure 10 A structural diagram of the rotor core 6 and stator core 4 in a multi-system rotary sensor 8, where the rotor core 6 serves as the outer rotor, is shown. The rotor core 6 is located on the outer diameter side relative to the stator core 4. The rotor core 6 has a plurality of convex rotor magnetic poles 24 that are equally spaced in the circumferential direction and vary in inner diameter, while the stator core 4 has a plurality of stator magnetic poles 21 that protrude outwardly at equal intervals in the circumferential direction. The rotor core 6 and stator core 4 are arranged opposite to each other. Then, a shaft 3 is connected to the outer diameter side of the rotor core 6. Here, the rotor core 6 and the shaft 3 can also be integrated.

[0076] <Effect>

[0077] Next, regarding the effects of this embodiment, the following will be discussed. Figure 10 The following explanation is provided. As described above, the rotor core 6 is located on the outer diameter side relative to the stator core 4. Therefore, depending on the manufacturability of the multi-system rotation sensor or the situation of the peripheral equipment for installing the multi-system rotation sensor, while changing the structure from the structure of Embodiment 1 where the rotor core 6 is located on the inner diameter side relative to the stator core 4 to the structure of this embodiment where the rotor core 6 is located on the outer diameter side relative to the stator core 4, the same effect can be obtained, thereby improving the manufacturability of the multi-system rotation sensor.

[0078] Implementation method 4.

[0079] <Dual-system parallel structure>

[0080] Figure 11 and Figure 12 This diagram illustrates an example of the wiring of the first system winding 9 in a multi-system rotary sensor 8, which implements two system windings 16. As described above, a system winding of one system is wound on each stator pole 21. Then, the system windings 16 of the same system wound on each stator pole 21 are connected in parallel. Figure 11 This illustrates a wiring example where all system windings are connected in parallel. For example... Figure 11 As shown, in the parallel configuration, a terminal block 31 is provided to connect each stator pole. However, it is also possible to connect the stator poles via transition wires without using the terminal block 31. Furthermore, the system windings can be connected in series or parallel, as shown below. Figure 12 As shown, series and parallel connections can be mixed. Furthermore, this structure is not limited to the above-described structure and is applicable to multi-system rotary sensors based on two or more systems.

[0081] <Effect>

[0082] Next, regarding the effects of this embodiment, the following will be discussed. Figure 11 and Figure 12 The following explanation is provided. As described above, the system windings 16 of the same system wound on each stator pole 21 are connected in parallel. Therefore, the resistance of each system winding 16 can be minimized. Furthermore, as described above, the system windings only need to be connected, for example, as... Figure 12 As shown, series and parallel connections can be mixed. Therefore, regardless of the wiring structure of each system winding of the rotating electric motor 2, the same effects as in Embodiment 1 can be achieved, improving the manufacturability of the windings or increasing the design freedom of the electric motor.

[0083] Implementation method 5.

[0084] <Structures with three or more systems>

[0085] Figure 13 This is a diagram showing the circuit structure of a multi-system rotary sensor 8 when N systems (three or more systems) are implemented. (See diagram for example.) Figure 13 As shown, the stator winding 5 of the multi-system rotary sensor 8 is composed of system windings 9, 13, 14, and 15 of N systems. Each system winding 16 is composed of a first output winding 10, a second output winding 11, and an excitation winding 12. The first output winding 10 and the second output winding 11 of each system are connected to the angle calculation unit 7, and the excitation winding 12 of each system is connected to the excitation circuit unit 1. Here, the angle calculation unit 7 and the excitation circuit unit 1 can be independent in each system, or they can be connected to a single excitation circuit unit 1 and angle calculation unit 7 in all systems. Figure 14 An example of a combination of rotor pole number R and stator pole number S is shown when the system number is 3. Figure 14 The combination shown is an example; any combination that satisfies formula (1) is acceptable.

[0086] Figure 15 An example of the configuration of each system winding 16 is shown when three system windings are implemented. As described above, if the number of systems of system winding 16 is set to N, the number of rotor poles of rotor core 6 is set to R, and n is set to a natural number, then stator core 4 has the number of stator poles S as shown in formula (1). Figure 15 The case where R=4, N=3, n=2, and S=24 is shown.

[0087] The stator pole positions of each system winding 16 are arranged in a four-fold rotationally symmetrical manner relative to the rotor's axis of rotation. Specifically, the first system winding 9 is wound around stator poles (B, H, N, T) and stator poles (E, K, Q, W). The second system winding 13 is wound around stator poles (C, I, O, U) and stator poles (F, L, R, X). The third system winding 14 is wound around stator poles (D, J, P, V) and stator poles (G, M, S, A).

[0088] Furthermore, each system winding 16 can be configured to be rotationally symmetrical about four times with respect to the rotor's axis of rotation. For example, as... Figure 16 The first system winding 9 is wound on stator poles (B, H, N, T) and stator poles (C, I, O, U). The second system winding 13 is wound on stator poles (D, J, P, V) and stator poles (E, K, Q, W). The third system winding 14 is wound on stator poles (F, L, R, X) and stator poles (G, M, S, A). The configuration of the system windings in systems with N>3 can also be carried out in the same manner. That is, the winding configuration of each system winding wound on each stator pole is a structure that is R-fold rotationally symmetrical with respect to the rotor's rotation axis.

[0089] <Effect>

[0090] This structure allows for the construction of multiple systems with N≥3, ensuring operation even in the event of a winding failure in two or more systems. Furthermore, the same effect is achieved in multiple systems with N≥3 as in the case of N=2.

[0091] Implementation method 6.

[0092] <Structure of the main system and auxiliary systems>

[0093] Figure 17 An example of the configuration of the system winding 16 in the multi-system rotary sensor 8 with a system number of 2 is shown. If the system number of the system winding 16 is set to N=2, the number of rotor poles of the rotor core 6 is set to R, and n is set to a natural number, then the stator core 4 has the stator pole number S shown in formula (1). Figure 17 The diagram shows the cases where R=4, N=2, n=3, and S=24. The stator pole positions of each system winding 16 are arranged in a manner that is four times rotationally symmetrical about the circumference relative to the rotor's axis of rotation. That is, the first system winding 9 is wound around stator poles (B, H, N, T), stator poles (C, I, O, U), stator poles (D, J, P, V), and stator poles (E, K, Q, W). The second system winding 13 is wound around stator poles (F, L, R, X) and stator poles (G, M, S, A).

[0094] In this structure, the number of stator poles 21 wound by each system winding 9 and 13 varies between systems. This is an example, provided that the number of stator poles S satisfies formula (1), and the stator pole positions wound by each system winding 16 are configured in a structure that is R-fold symmetrical along the circumference. That is, the winding configuration of each system winding wound on each stator pole is configured in a manner that is R-fold rotationally symmetrical with respect to the rotor's rotation axis.

[0095] <Effect>

[0096] This structure increases the number of stator poles wound in the first system winding 9, which is the main system. Compared to the case where the number of stator poles 21 wound in each system winding 16 is the same across systems, this improves the angle detection accuracy of the main system. Furthermore, although in Figure 17 The example shown is for N=2, but it is not limited to this; the same effect can be obtained if the integer is N≥2.

[0097] Implementation method 7.

[0098] <Structure when this rotary sensor is mounted on an electric power steering system>

[0099] The multi-system rotation sensor described above can be applied to electric power steering systems in vehicles. The following section uses... Figure 18 To illustrate the electric power steering device involved in Embodiment 7.

[0100] Figure 18 This is a structural diagram of an electric power steering system in a car. When the driver steers the steering wheel (not shown), the torque is transmitted to shaft 41 via the steering shaft (not shown). At this time, the torque detected by the torque sensor 42 is converted into an electrical signal and transmitted to the first system power supply 43 and the second system power supply 44 via cables (not shown). On the other hand, vehicle information such as vehicle speed is converted into electrical signals and transmitted to the first system power supply 43 and the second system power supply 44 via cables. The first system power supply 43 and the second system power supply 44 calculate the required auxiliary torque based on the vehicle information such as torque and vehicle speed, and supply current to the rotary motor 2 via the ECU (Electric Control Unit) 49. The rotary motor 2 is configured parallel to the direction of movement of the rack shaft (indicated by the arrow). Furthermore, the power supply to the first system power supply 43 and the second system power supply 44 is transmitted from the battery or alternator via power connectors 46 and 47. The torque generated by the rotary motor 2 is reduced by a gearbox 52 containing a drive belt (not shown) and ball screws (not shown), thereby generating a thrust that moves the rack shaft (not shown) located inside the housing 54 in the direction of the arrow to assist the driver's steering force.

[0101] Consequently, link 40 moves, the wheels steer, and the vehicle can turn. Assisted by the torque of rotary motor 2, the driver can turn the vehicle with less steering force. Furthermore, rack and pinion sleeve 53 is configured to prevent foreign objects from entering the device. Figure 1 As described, the multi-system rotation sensor 8 is mounted on the shaft 3 of the rotary motor 2. The multi-system rotation sensor 8 detects the rotation angle of the rotor of the rotary motor 2 and outputs a corresponding angle signal. Power is supplied from the power supply 45 to the ECU 49 via a power connector.

[0102] In such an electric power steering system, since the cogging torque or torque ripple generated by the rotary motor is transmitted to the driver through gears, it is desirable to have a low cogging torque or torque ripple in order to obtain a good steering feel. In addition, it is also desirable to have low vibration and noise when the rotary motor is operating.

[0103] <Effect>

[0104] By mounting the multi-system rotation sensor 8 described in embodiments 1 to 6 onto the electric power steering system, the effects described in each embodiment can be obtained. Specifically, by suppressing the angle detection error of the multi-system rotation sensor 8, the angle detection accuracy can be improved, thereby achieving a comfortable steering feel. Furthermore, the multi-system rotation sensor 8 can be configured as multiple systems with three or more systems, enabling operation even in the event of a failure in the windings of two or more systems. Thus, even in the event of a failure, an auxiliary force for safe steering can be output.

[0105] in addition, Figure 1 The excitation circuit section 1, angle calculation section 7, and shown are... Figure 18 The ECU49 shown can also be composed of microstructures. Figure 19 An example of the hardware of the microcomputer comprising the excitation circuit unit 1, the angle calculation unit 7, and the ECU is shown. It consists of a processor 500 and a storage device 510. Although not shown, the storage device 510 includes a volatile storage device such as random access memory and a non-volatile auxiliary storage device such as flash memory. Alternatively, an auxiliary storage device such as a hard disk can be used instead of flash memory. The processor 500 performs angle calculations, such as those in the angle calculation unit 7, by executing a program input from the storage device 510. In this case, the program is input from the auxiliary storage device to the processor 500 via the volatile storage device. Furthermore, the processor 500 can output data such as calculation results to the volatile storage device of the storage device 510, or save data to the auxiliary storage device via the volatile storage device.

[0106] In addition, the hardware in the excitation circuit section 1, the angle calculation section 7, and the ECU49 may not be a microcomputer, but may be an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), a simple logic circuit, or a relay, etc.

[0107] This disclosure describes various exemplary embodiments and examples, but the various features, forms and functions described in one or more embodiments are not limited to the application of a specific embodiment, and can be applied to the embodiment alone or in various combinations.

[0108] Therefore, it can be assumed that numerous variations not illustrated are also included within the scope of the technology disclosed in this application. For example, this includes cases where at least one constituent element is modified, added to, or omitted, and cases where at least one constituent element is extracted and combined with constituent elements of other embodiments.

[0109] Label Explanation

[0110] 1: Excitation circuit section, 2: Rotary motor, 3: Shaft, 4: Stator core, 5: Stator winding, 6: Rotor core, 7: Angle calculation section, 8: Multi-system rotation sensor, 9: First system winding, 10: First output winding, 11: Second output winding, 12: Excitation winding, 13: Second system winding, 14: Third system winding, 15: Nth system winding, 16: System winding, 21: Stator pole, 24: Rotor pole, 30: Transition wire, 31: Terminal block.

Claims

1. A multi-system rotation sensor, comprising: The multi-system rotary sensor comprises a stator core with S magnetic poles arranged at equal intervals, stator windings wound around the magnetic poles, and a rotor core with R magnetic poles arranged opposite to the stator core, wherein the stator windings are composed of system windings of number N, where N is a natural number greater than 2. The stator winding consists of an excitation winding and a two-phase output winding. The number of magnetic poles S in the stator core, the number of magnetic poles R in the rotor core, and the number of system windings N in the stator winding have a relationship of S = nRN. In the S magnetic poles of the stator core, each system winding is divided and wound with every R magnetic poles. The winding configuration of each system winding is arranged to be R-fold rotationally symmetric with respect to the rotor's rotation axis, where n is a natural number. During operation, by applying voltage to the excitation windings of each system, a sinusoidal voltage with a frequency corresponding to the number of magnetic poles R of the rotor core relative to the rotation frequency is induced in the two-phase output windings of each system, and the rotor angle is calculated based on the phase of the sinusoidal voltage.

2. The multi-system rotation sensor as described in claim 1, characterized in that, In the stator winding, in the circumferential direction of the stator core, the system windings of the same system are wound with the same number of turns around the magnetic pole located at each S / R.

3. The multi-system rotation sensor as described in claim 1, characterized in that, Different system windings are wound on every other magnetic pole of the stator core.

4. The multi-system rotation sensor as described in claim 1, characterized in that, Different system windings are wound on every S / RN magnetic poles of the stator core.

5. The multi-system rotation sensor as described in any one of claims 1 to 3, characterized in that, Each system winding is wound around the S / N poles of the stator core.

6. The multi-system rotation sensor as described in any one of claims 1 to 3, characterized in that, Depending on the system, the number of magnetic poles of the wound stator core will also be different.

7. An electric power steering device, characterized in that, It is equipped with a multi-system rotation sensor as described in any one of claims 1 to 6.

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