Failure determination device for rotating machine control device and failure determination method

A failure determination device for a rotating machine control device, the failure determination device comprising:

• a power converter to supply power to a rotating machine;
• a current detector to detect a rotating machine current to be supplied to the rotating machine;
• a first angle sensor to generate at least two electrical signals in accordance with a rotation angle of the rotating machine;
• a first sine wave signal output device to output a first sine wave signal and a second sine wave signal based on the at least two electrical signals generated by the first angle sensor;
• a first angle calculator to output a first angle detection value based on the first sine wave signal and the second sine wave signal;
• a second angle sensor to generate at least two electrical signals in accordance with the rotation angle of the rotating machine;
• a second sine wave signal output device to output a third sine wave signal and a fourth sine wave signal based on the at least two electrical signals generated by the second angle sensor;
• a second angle calculator to output a second angle detection value based on the third sine wave signal and the fourth sine wave signal;
• a rotation angle estimator to output a rotation angle estimation value with respect to the rotation angle of the rotating machine based on the rotating machine current an angle sensor failure determiner to detect failure of the first angle sensor and the second angle sensor;
• and
• a current detector abnormality determiner to detect failure of the current detector based on the rotating machine current,
• wherein the angle sensor failure determiner determines the failure of the first angle sensor or the second angle sensor based on at least two of:
• a difference between the rotation angle estimation value and the first angle detection value;
• a difference between the rotation angle estimation value and the second angle detection value;
• and
• a difference between the first angle detection value and the second angle detection value, and
• wherein the angle sensor failure determiner determines the failure of the first angle sensor or the second angle sensor when the current detector abnormality determiner does not detect the failure of the current detector.

A failure determination method for a rotating machine control device adjusting power to be supplied from a power converter to control a rotating machine, the failure determination method comprising:

• generating a first sine wave signal and a second sine wave signal based on at least two electrical signals generated by a first angle sensor in accordance with a rotation angle of the rotating machine;
• generating a first angle detection value based on the first sine wave signal and the second sine wave signal;
• generating a third sine wave signal and a fourth sine wave signal based on at least two electrical signals generated by a second angle sensor in accordance with the rotation angle of the rotating machine;
• generating a second angle detection value based on the third sine wave signal and the fourth sine wave signal;
• obtaining a rotation angle estimation value with respect to the rotation angle of the rotating machine based on a rotating machine current to be supplied to the rotating machine, which is detected by a current detector;
• detecting failure of the power converter based on a power converter failure detector;
• detecting failure of the first angle sensor or the second angle sensor based on at least two of:
• a difference between the rotation angle estimation value and the first angle detection value;
• a difference between the rotation angle estimation value and the second angle detection value;
• and
• a difference between the first angle detection value and the second angle detection value;
• and
• detecting the failure of the first angle sensor or the second angle sensor when the power converter failure detector does not detect the failure of the power converter.