NXP Semiconductors DSP56800E, Руководство пользователя

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Equation 33
Considering that normalized magnitudes of basic space vectors are |U
60
| = |U
0
| = 2 / √3,
and by the substitution of the trigonometric expressions sin 60° and tan 60° by their
quantities 2 / √3, and √3, respectively, the
Equation 33 on page 42 can be rearranged for
the unknown duty-cycle ratios T
60
/ T and T
0
/ T as follows:
Equation 34
Sector II is depicted in Figure 2-9 . In this particular case, the reference stator voltage
vector U
S
is generated using the appropriate duty-cycle ratios of the basic switching
states T
60
and T
120
. The basic equations describing this sector are as follows:
Equation 35
where T
120
and T
60
are the respective duty-cycle ratios, for which the basic space vectors
U
120
and U
60
should be applied within the time period T. T
null
is the time, for which the
null vectors O
000
and O
111
are applied. These resultant duty-cycle ratios are formed from
the auxiliary components, termed A and B. The graphical representation of the auxiliary
components is shown in
Figure 2-10 .
GMCLIB_SvmStd
GMCLIB User's Guide, Rev. 2, 10/2015
42 Freescale Semiconductor, Inc.