To provide a permanent magnet temperature sensor which can estimate the temperature of a permanent magnet in a permanent magnet motor including the permanent magnet disposed in a rotor, provide the permanent magnet motor which can estimate the temperature of the permanent magnet disposed in the rotor, and provide a drive system which can suitably drive such a permanent magnet motor in response to the estimated temperature of the permanent magnet.
The motor 1 includes the rotor 3 having a rotor core 31 and the permanent magnet 32 disposed in this rotor core 31, and a stator 2. Further, the motor 1 includes a magnetized element 5 disposed near the permanent magnet 32 and magnetized by the leakage magnetic flux of the permanent magnet, and a Hall element 6 disposed in the stator to measure the intensity of a magnetic field generated from the magnetized element. When the temperatures of the permanent magnet 32 and the magnetized element 5 are raised, the intensity of the magnetic field generated from the magnetized element 5 is lowered, and hence the temperature of the permanent magnet 32 can be estimated.
Takashi Tomizawa
Ikuo Yamanaka
Akika Okado
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