Mitsubishi Electric FR-E800 Series Instruction Manual page 96

• It is applicable to fast response applications with which induction motors were previously regarded as difficult to use.
Applications requiring a wide variable-speed range from extremely low speed to high speed, frequent acceleration/
deceleration operations, continuous four-quadrant operations, etc.
• Torque control is enabled (when an induction motor is used).
• It allows servo-lock torque control which generates a torque in the motor shaft while stopped. (Not available under Real
sensorless vector control.)
Block diagram of Real sensorless vector control
Magnetic
φ 2
flux
control
ω *
Speed
+
control
-
ω FB
+
ω FB
+
ω s
Speed estimation
Pre-excitation
id *
+
current
control
-
id
Torque
iq
*
+
current
control
-
iq
ω 0
iq
Slip
calculation
iq
φ 2
Magnetic
flux
calculation
PWM
modulation
Vd
Output
voltage
conversion
Vq
ω 0
id
Current
iq
conversion
id
Vd
Vq
4.1 Vector control and Real sensorless vector control
1
2
3
I M
4
5
6
7
8
9
10
95
4. Control Method