JPH01282419A - Position/speed detector - Google Patents

Abstract

PURPOSE:To achieve a higher linearity in the detection of an angle, by adding and subtracting both terminal voltages of a multi-phase coil to calculate a position of rotation of a rotor from a phase of an addition/subtraction signal and a rotational speed from a frequency. CONSTITUTION:Two rotors 1(11 and 12) which are cylindrical and have teeth 2 formed at a fixed pitch Pr in the inner circumference thereof are arranged overlapping each other, stators 3(31 and 32) are arranged inside the rotor 1 and the stator 3 is provided with salient poles 4 (41-416). Teeth 5 are provided as opposed to the teeth 2 at the tip of the salient poles 4 and the salient poles 4 are wound respectively with coils 6 (61-616). The teeth 5 of the salient poles are shifted by Pr/3ns (ns: the number of the teeth of the salient poles 4) in phase according to an array direction. Hence, the teeth 5 can be used as vernier. In addition, in these coils 6, a voltage Vcosomegat is applied to the stator 31 while a voltage Vsinomegat to the stator 32 respectively from power sources 81 and 82. Then, a position of rotation of a rotor can be detected from a phase as give with the by addition and subtraction of both terminal voltages of coils in respective phases and a rotational speed from, a frequency.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in a device for detecting position and velocity using a magnetic resolver.

[Prior Art] Conventionally, as a position/velocity detection device using a magnetic resolver, there has been one using a two-phase excitation resolver phase shifter shown in FIG. 5, for example.

In the figure, 81 to S4 are primary coils provided on the stator side, E and E2 are coils S, S3 and S2. The signal source that drives S is a secondary coil provided on the rotor side.

In such a device, the signal sources E1 and E2 are Vs i n
With AC voltages ωt and Vcosωt (■ is the amplitude of the AC voltage, ω is the angular velocity, and t is the time), the coils S+, Sx and S2
When +S4 is driven, the following voltage E0 is generated in the secondary coil So.

Eo = KO (Vs i nωt cos θ ten V cos ω
tsinθ) = K(, Vs in (ωt±θ) Ko: change ratio, θ: rotor rotation angle As shown in this equation, the secondary coil has the rotor rotation angle θ
voltages that are out of phase by

[Problem to be solved by the invention] However, since the voltage detected by the secondary coil in this way contains harmonic components, the detected waveform of the detection signal contains many errors, making it difficult to detect angles. There was a problem that linearity was poor.

The present invention has been made to solve these problems, and aims to realize a position/velocity detection device that has few harmonic components included in the angle detection signal and has good angle detection linearity. shall be.

[Means for Solving the Problems] The present invention provides a rotor in which teeth are formed with a pitch Pr, and teeth in multiples of M (M
is an integer) salient poles are formed at the tips of the salient poles, facing the teeth of the rotor and having a pitch of (Pr/kns) ng: 1 the number of teeth in the salient poles: M is an even number When the multiple M of 3 is a multiple of 3, an even number of teeth are provided that are different from the teeth of the rotor, and adjacent salient poles have a stator whose phase is shifted by Pr/M, and a stator whose teeth are in the same phase. an M-phase coil, in which one phase is a coil wound around a salient pole formed with a The teeth of the core part are stacked with a phase shift of Pr/4, and the two stator coils are connected to each other at Vos6)t.
and Vs 1 nωt, and a calculation unit that adds and subtracts the voltages across the coils of each phase, and calculates the rotational position of the rotor from the phase of the addition and subtraction signals, and the rotational speed from the frequency. This is a position/velocity detection device.

[Example] Hereinafter, the present invention will be explained using the drawings.

FIG. 1 is a configuration diagram of an embodiment of a position/velocity detecting device according to the present invention, in which (a) is a plan view and (b) is a sectional view taken along the line X--X in FIG. (a).

In the figure, reference numeral 1 denotes a rotor having a cylindrical shape and teeth 2 having a constant pitch Pr formed on the inner periphery, and two rotors 11 and 12 are provided one on top of the other.

3 is a stator placed inside the rotor 1. The stator 3 has 4N salient poles (N is an integer), for example, 16 salient poles.
~416 are provided. Teeth 5 opposing the teeth 2 are provided at the tips of these salient poles. Further, coils 61 to 6°6 are wound around each salient pole. In Figure 0, only the coil 6 wound around the salient pole 41 is shown.

Such a stator 3 is 3. and 32 are insulating members 7
They are placed one on top of the other.

Further, the rotor 1 and the stator 3 are constructed by laminating steel plates.

81 and 82 are the coils of stators 31 and 32, EC=V
The intersection of cosωt and E6 = Vs i nωt? It is a signal source that provides h voltage (V is voltage amplitude).

FIG. 2 shows the detailed structure of the rotor and stator.

This figure shows the rotor and stator exploded.

In the figure, n9 teeth are formed within one salient pole (
In the case of the figure, ng = 4), and the salient poles are 41°42.
43.4a has a phase of O and (1/4) Pr with respect to the tooth 2 of the rotor 1, respectively.

They are shifted by <2/4)Pr and (3/4)Pr.

A total of 16 salient poles are provided, and four salient poles are provided for each phase. One phase is formed by coils wound around salient poles that are in the same phase.

The phase shift is O, (1/4) pr.

Let the coils wound around the salient poles of <2/4)Pr and (3/4)Pr be A-phase, B-phase, C-phase, and D-phase coils, respectively. The pitch ps of the teeth 5 of the salient pole is Ps=Pr (P
As a result, the teeth 5 of the salient pole are shifted in phase by P r /B n S in accordance with the arrangement direction, and therefore, the teeth 5 can be used as a vernier.

The rotors 11 and 12 are superimposed with the teeth 2 having the same phase. Also, stator 3. and 32 are superimposed with the phase of the tooth 5 shifted by P r /4.

Each coil of the stator is connected as shown in FIG.

In FIG. 3, Ll is a coil in which A-phase and B-phase coils are connected in series, and L2 is a coil in which C-phase and D-phase coils are connected in series. Stator 3 is attached to these coils. Then V co
A voltage Vsinωt is applied to the stator 32.

Then, the voltage generated in the coil is detected via a resistor, an amplifier, and a subtracter.

Next, the operation of such a device will be explained.

The voltages S I + S2 + s3 + Sa generated in the A-phase, B-phase, C-phase, and D-phase coils are as follows.

1: order of teeth, E: amplitude voltage m ) 1 m2 +...ml: constant The voltage S1+52-'3z Sa obtained by adding and subtracting these voltages is as follows.

From the formula S 1 + , S , “ 5 )−5<0, 2n
+th order and 3n2nd order (n+, n2 is an integer) harmonic components are removed. The harmonics of the fifth order and above have little influence and can be ignored. Therefore, the detected voltage becomes like a thorn.

S, + to -53-82A, 赫(9suCp) where, AO
is a constant, ψ is the initial phase, and corresponds to the equation 0.

FIG. 4 shows a vector diagram of each voltage 81 to s4.

As shown in this figure, the second harmonic component is eliminated by taking the difference between the combined vector of voltages S and 52 and the combined vector of voltages s3 and 84, and the teeth provided on the salient poles are turned into verniers.
The next harmonic component is eliminated.

As a result, the voltage detected at the stator 31 is vs=EC(S,+82S:l54)=Vc
The detection signals vs1 and VS2 in FIG. 3, which are osωt−As i n (θ+ψ), correspond to s, +s2, and Sco+S4, respectively.

Further, the voltage detected by the stator 32 is VB = ES
(S T 1 S 2 S co -34)=Vsi
The detection signals VC+ and VO2 in FIG. 3, which are nωt-Acos (θ+95), correspond to 84+s2 and Sco+S4.

From this, the signal detected by the circuit in Fig. 3 is: ■ ding=vs-Vc=Vcosωt-As in (θ+ψ)-Vsin
ωt−Acos (θ+95)=AVS i n (θ
+95-ωt), and the phase of the detection signal is modulated by the rotation angle θ of the rotor. Therefore, by reading this phase, the rotation angle can be detected.

In addition, although the case where a 4-phase coil was used was explained in the example, the number of phases of the coil may be other than this. For example, when a 3-phase coil is used, the phase of the teeth of adjacent salient poles is the same as that of the rotor. The third harmonic component is removed by shifting P r / 3 with respect to the teeth of the salient pole, and the teeth of the salient pole are shifted by P r / 3 with respect to the pitch of the rotor.
A vernier configuration shifted by r/2ns is used to remove second-order harmonic components.

Furthermore, in the embodiment, a case has been described in which harmonic components are removed by detecting signals of s, -s, -s in both stators 31 and 32, but harmonic components can also be removed by other additions and subtractions. For example, in the stator 31, s,
+s2-83-84 removes harmonic components and stator 3
2, harmonics may be removed by 83 +53-s and -81. In this case, in the stator 32, the B-phase and C-phase coils are connected in series, and the A-phase and D-phase coils are connected in series.

Also, the pitch of the teeth of the salient pole is Not limited to Pr (Pr/3ns) It may be Pr + (Pr/3n6).

Further, the teeth of the salient poles of the stator 32 may be in the same phase as the teeth of the salient poles of the stator 3°.

[Effect] According to the present invention, the second harmonic and the third harmonic generated in the detection voltage of the coil are removed by using the multiphase coil and the teeth of the salient pole that are vernier with respect to the teeth of the stator. Therefore, the error in the detection signal is reduced and the linearity of angle detection is improved.

[Brief explanation of the drawing]

FIG. 1 shows the position according to the present invention. A configuration diagram of an embodiment of the speed detection device, FIG. 2 is a configuration diagram of the main parts of FIG. 1, and FIG. 3 is a configuration diagram of the detection circuit of the device in FIG.
Figure 4 is a vector diagram of the coil voltage of the device in Figure 1;
The figure is a diagram showing an example of the configuration of a conventional position/velocity detection device. 1.1+, 12... Rotor, 2.5... Teeth, 3°3+, 32... Stator, 41-416... Salient pole, 6... Coil, 81.8□... signal source. Tsune]

Claims (1)

[Claims] A rotor with teeth formed at a pitch Pr, and a multiple of M (M is an integer) salient poles are formed, and the tips of the salient poles are opposed to the teeth of the rotor. The pitch is (Pr/kns) ns: Number of teeth in 1 salient pole k: When M is an even number, a multiple of 3 When M is a multiple of 3, an even number of teeth are provided that are different from the teeth of the rotor, and The stator comprises a stator in which the phases of the teeth are shifted by Pr/M between matching salient poles, and an M-phase coil in which one phase is a coil wound around the salient poles on which teeth of the same phase are formed, and the rotor and two stators are provided, and the teeth of the rotor are stacked with the same phase, and the teeth of the stator are stacked with a phase shift of Pr/4, and the coils of the two stators are stacked, respectively. A signal source that provides alternating current voltages Vcosωt and Vsinωt, and a calculation unit that adds and subtracts voltages across the coils of each phase, and calculates the rotational position of the rotor from the phase of the addition and subtraction signals, and the rotational speed from the frequency. Position/speed detection device.