WEG ECW500, Руководство пользователя

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Functional Description .
ECW500 | 43
Figure 6.12 Operation of the ECW500 in the MTVC DROOP mode
6.5.5 MPFC (Power Factor Control)
(Mode: Power Factor Control) In this mode, the ECW500 controls the excitation, so that the power factor at the
terminals of the machine is maintained constant based on the control reference in this mode. In this mode, the
synchronous machine operates connected to the bus (online).
NOTE!
A positive reference (+) in this mode indicates that the synchronous machine operates with a
capacitive characteristic (current leads voltage), providing reactive power to the system.
Otherwise a negative reference (-) indicates that the synchronous machine operates with an
inductive characteristic (current lags voltage), absorbing reactive power from the system.
Figure 6.13 Operation with positive and negative references in MPFC mode
6.5.6 MRPC (Var Control)
(Mode: Terminal Reactive Power Control) In this mode, the ECW500 controls the excitation so as to guarantee
that the reactive power at the terminals of the synchronous machine follow the reference of the control. In this
mode, the synchronous machine operates connected to the power supply (online).
NOTE!
A positive reference (+) in this mode indicates that the synchronous machine will provide reactive
power to the system, and a negative reference (-) indicates that the synchronous machine will
absorb reactive power from the system.
6.5.7 Switching Between Operating Modes
Changing from one operating mode to another depends on the application of appropriate commands via digital
input, HMI or supervision software, besides the specific offline (30206) and online (30208) programming modes.