Control Diagram; Controllers - ABB ACS 600 User Manual

Control Diagram

Hysteresis
Torque ref.
Flux ref.

Controllers

ACA 635 IGBT Supply Sections
A block diagram of the measurements and principle of the ISU control
program is shown below. S1, S2 and S3 denote the power switches.
Direct torque and flux
hysteresis control
Torque bits
Flux bits
Control bits
Actual
Actual
flux
torque
Actual value
calculation
Reference value
calculation
DC voltage
control
Switching
frequency control
Switching frequency reference
The control includes two main controllers:
• torque and flux hysteresis control
• dc voltage controller
On the basis of measurements the following items are calculated:
• actual value for flux
• actual value for torque
• actual value for reactive power
• estimate for frequency
Chapter 6 – Firmware Description
ASICs
Optimal
S1, S1, S3
switching
logic
DC voltage
S1, S2, S3
Current
L
Supply network
6-11