MSD Multi-Axis System Operation Manual DC-AC Servo Drive
77
9 Planning
AC-AC
Servo Drive
DC-AC
Servo Drive
Motor
DC-AC
Servo Drive
Braking
resitance
AC mains connection
central DC link
Motor
Motor
Figure 9.2 Block diagram of a multi-axis system with AC-AC Servo Drive as supply
9.4 Operation with AC-AC Servo Drive as
supply
Advantages
•
The investment costs are lower than on operation with a Power Supply Unit
•
As an additional Power Supply Unit is not required, in general the space
required is less than on operation with a Power Supply Unit
•
Regenerative power is available to the other axes via the central DC link
•
Surplus energy is dissipated centrally via the AC-AC Servo Drive's braking
resistor
Disadvantages
•
In this system variant, in general it is not possible to operate all axes at full rated
power, as otherwise the DC link on the AC-supplied AC-AC Servo Drive may be
overloaded
•
It may be necessary to oversize the supplying AC-AC Servo Drive
•
Regenerative power cannot be fed back to the supply system, instead it can
only be converted into heat via a braking resistor
•
Similar to the AC-AC Servo Drive, it may be necessary to oversize the braking
resistor, as a consequence the heat produced causes additional effort for
installation and temperature control
•
The operating costs are higher than for a system comprising AC-AC Servo
Drives or with a Power Supply Unit
•
Lower DC link voltage than on operation with a Power Supply Unit
•
Due to the total DC link capacitance, fewer DC-AC Servo Drives can be
connected than to the Power Supply Unit
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Id. no.: CA97554-001 0
5
/2017