The d-axis current error integrator 37g
multiplies each of the sin component Id_err_sin of the d5 axis current variation error Id_err and the cos component
Id_err_cos of the d-axis current variation error Id_err by
the correction gain k according to Expressions (13.1) and
(13.2), and adds Id_err_sin_i_old and Id_err_cos_i_old to
each multiplication result. Id_err_sin_i in Expression
10 (13.1) is an integral value of Id_err_sin up to the current
mechanical angle cycle, and Id_err_cos_i in Expression
(13.2) is an integral value of Id_err_cos in the current
mechanical angle cycle. Further, Id_err_sin_i_old in
Expression (13.1) is Id_err_sin_i up to the previous
15 mechanical angle cycle, and Id_err_cos_i_old in Expression
(13.2) is Id_err_cos_i in the previous mechanical angle
cycle.
(13.1)
(13.2)
[0049] The d-axis current error correction value
20 demodulator 37h calculates the d-axis current error
correction value ∆Id according to Expressions (14.1) and
(14.2). As a result, the phase of the d-axis current
variation error is inverted, and an instantaneous value of
the d-axis current error correction value ∆Id at the
25 mechanical angle phase θm is generated.
( ) ∫
π
θθ⋅
π = 2
0 err_sin_d I err_d sin d mm
1 I
( ) ∫
π
θθ⋅
π = 2
0 err_cos_d err_d dcosI mm
1 I
err_sin_di_err_sin_d old_i_err_sin_d I +⋅= IkI
err_cos_di_err_cos_d old_i_err_cos_d I +⋅= IkI
18
Docket No. PFGA-22154-IN,TH: FINAL
18
(14.1)
(14.2)
[0050]
FIG. 3 is a diagram illustrating a configuration
5 example of the correction torque limit value generator of
the first embodiment of the present disclosure. In FIG. 3,
the correction torque limit value generator 38 includes a
current amplitude calculator 38a, a peak hold calculator
38b, a subtractor 38c, and a ∆T limit value generator 38d.
10 [0051] The current amplitude calculator 38a calculates a
current command value amplitude Ia* according to Expression
(15) based on the d-axis current command value Id* and the
q-axis current command value Iq*, and outputs the
calculated current command value amplitude Ia* to the peak
15 hold calculator 38b.
(15)
[0052] The peak hold calculator 38b acquires a maximum
value of the current command value amplitude Ia* in each
predetermined acquisition period Tm as a current command
20 peak value Ia*_peak for each acquisition period Tm, and
outputs the acquired current command peak value Ia*_peak to
the subtractor 38c. For example, the predetermined
acquisition period Tm corresponds to a mechanical angle
cycle of the motor M.