Patent ID: 11926378
Assignee: NIDEC CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC B  H | IPC B  H

Claim 5:
6. The drive controller according to claim 5, wherein
the fault determination unit is configured to use expressions below that are each expressed as the positive or the negative of the contribution component,

q_affect(a)=sgn(−sin θ)

q_affect(b)=sgn(−sin θ−2π/3)

q_affect(c)=sgn(−sin θ−4π/3)

d_affect(a)=sgn(cos θ)

d_affect(b)=sgn(cos θ−2π/3)

d_affect(c)=sgn(cos θ−4π/3)

where each of the q_affect (a), the q_affect (b), and the q_affect (c) indicates a positive or a negative of a contribution component of a q-axis electric value in corresponding one of an a-phase, a b-phase, or a c-phase,
each of the d_affect (a), the d_affect (b), and the d_affect (c) indicates a positive or a negative of a contribution component of a d-axis electric value in corresponding one of the a-phase, the b-phase, or the c-phase,
θ is an electrical angle of the three-phase motor, and
sgn (x) is expressed as −1 when x is less than 0, as 0 when x is 0, and 1 when x is more than 0.