SENSORLESS FIELD ORIENTED CONTROL OF BRUSHLESS ...

Figure 5.1 – Torque control of sinusoidal motor.
ref
ref T
T KTIp Ip
(5.1)
K
sin( )
* ref
iA Ip
r
* ref
iB Ip
sin( r
120
)
* ref
iC Ip
sin( r
120
)
T
To impress the currents, an ideal hysteresis regulator will be used. It is shown in Figure 5.2 along
with its simpler representation.
Figure 5.2 – Hysteresis CRPWM.
The torque control of Figure 5.1 is implemented using the hysteresis CRPWM by generating the
appropriate current commands with reference to the rotor position, as shown in Figure 5.3. The
“sinusoidal commutator” 35 generates three-phase sinusoidal reference values. If the absolute
position sensor and the current regulators are assumed to be ideal this scheme provides perfect
torque control. The current reference signals generated are those shown in Figure 5.8-c.
35 The idea for using the term “sinusoidal commutator” in this fashion was taken from [99].
(5.2)
210