Redundant resolver and rotation angle detection device using same
A redundant resolver is configured of a stator and a rotor that form a pair, wherein the rotor is a rotor with a shaft angle multiplier of Nx having Nx (Nx is a natural number) salient poles, the stator is such that n teeth T 1 to Tn, where n is a natural number, are disposed sequentially in a circumferential direction, configuring M systems by being divided into M in the circumferential direction, and having an angle of 360/M degrees when angles of the teeth configuring one system are totaled, a one-phase excitation winding and a two-phase output winding are wound around each of the teeth T 1 to Tn, excitation signals of the same frequency are applied by differing excitation circuits to the respective excitation windings, an output order per system is Nout (Nout is a natural number), and an abnormality is detected based on output signals of the M systems.
1. A redundant resolver comprising a rotor and a stator that form a pair, wherein
the rotor is a rotor with a shaft angle multiplier of Nx having Nx (Nx is a natural number) salient poles,
the stator is such that n teeth, where n is a natural number, are disposed sequentially in a circumferential direction, configuring M systems by being divided into M in the circumferential direction, and having an angle of 360/M degrees when angles of the teeth configuring one system are totaled,
a one-phase excitation winding and a two-phase output winding are wound around each of the n teeth, excitation signals of the same frequency are applied by differing excitation circuits to the respective excitation windings, an output order per system is Nout (Nout is a natural number), and
an abnormality is detected based on output signals of the M systems.
2. The redundant resolver according to claim 1 , wherein, when a failure occurs in one portion of the M systems, the excitation signal of the system in which the failure has occurred is stopped.
3. The redundant resolver according to claim 1 , wherein an excitation order per system is Ne±0.5 (Ne is a natural number), and the shaft angle multiplier of the rotor is an odd number.
4. The redundant resolver according to claim 1 , wherein an excitation order per system is Ne±(Ne is a natural number), and the shaft angle multiplier of the rotor is an even number.
5. The redundant resolver according to claim 1 , wherein an offset of each output signal of the M systems is corrected.
6. The redundant resolver according to claim 1 , wherein a phase difference between the excitation signals is within 60°.
7. The redundant resolver according to claim 1 , wherein the excitation signals are synchronized.
8. The redundant resolver according to claim 1 , wherein M is two.
9. The redundant resolver according to claim 1 , wherein the output windings of a first system and a second system are wound in the same direction or in mutually opposing directions.
10. The redundant resolver according to claim 1 , wherein, when an angle detected by the first system is θ 1 and an angle detected by the second system is θ 2 , it is determined that there is an abnormality when |θ 1 −θ 2 |>α or |θ 1 +θ 2 |>β (note that α and β are real numbers).
11. The redundant resolver according to claim 1 , wherein two systems are disposed at intervals of 180° in the circumferential direction.
12. The redundant resolver according to claim 1 , wherein two systems are disposed at intervals of 90° in the circumferential direction.
13. A rotation angle detection device, comprising:
the redundant resolver according to claim 1 ; and
an angle computing unit, connected to an output terminal of the redundant resolver, that calculates and outputs a detected angle of the rotor based on an output voltage of output windings of the redundant resolver.
14. The redundant resolver according to claim 1 , wherein an auxiliary tooth around which no output winding is wound is disposed in an end portion of a tooth block that is a series of teeth configuring one system.
15. The redundant resolver according to claim 14 , wherein amplitudes of numbers of turns of the two-phase output winding wound around one system differ.