NXP Semiconductors MCUXpresso, User Manual

Page: 26 / 50

Figure 19. Position FOC control mode
8.3 Switch between Spin and MID
User can switch between two main modes of application:
Spin
and
MID
(Motor identification).
Spin
is for control PMSM (see MCAT
FreeMASTER interface (Motor Control Application Tuning) ).
MID
is for motor parameters identification (see Motor parameter
identification using MID ). Actual mode of application is shown in
APP: State
variable watch. The mode change can be made by
APP: MID to Spin request
or
APP: Spin to MID request
variables watch. The result of the change mode request shows
APP: Fault
variable watch.
MID fault
occurs when parameters identification still runs or MID state machine is in the fault state.
Spin fault
occurs
when
M1 Application switch
variable watch is ON or
M1 Application state
variable watch is not STOP.
8.4 Identifying parameters of user motor
Because the model-based control methods of the PMSM drives provide high performance (e.g. dynamic response, efficiency),
obtaining an accurate model of a motor is an important part of the drive design and control. For the implemented FOC algorithms,
it is necessary to know the value of the stator resistance
R
s
, direct inductance
L
d
, quadrature inductance
L
q
, and BEMF constant
K
e
. Unless the default PMSM motor described above is used, the motor parameter identification is the first step in the application
tuning. This section shows how to identify user motor parameters using MID. MID is written in floating-point arithmetics. Each MID
algorithm is described in detail in
MID algorithms . MID is controlled via the FreeMASTER "Motor Identification" page shown in
Figure 20 .
NXP Semiconductors
Remote control using FreeMASTER
MCUXpresso SDK Field-Oriented Control (FOC) of 3-Phase PMSM and BLDC motors, Rev. 0, 01/2022
User Guide 26 / 50