Bus Regulation 2-47
The bus voltage regulation set point (Vreg) in the drive is fixed for each
voltage class of drive. The bus voltage regulation set points are identical to
the internal dynamic brake regulation set points VDB's.
To avoid over-voltage faults, a bus voltage regulator is incorporated as part
of the acceleration/deceleration control. As the bus voltage begins to
approach the bus voltage regulation point (Vreg), the bus voltage regulator
increases the magnitude of the output frequency and voltage to reduce the
bus voltage. The bus voltage regulator function takes precedence over the
other two functions. See Figure 2.13
.
The bus voltage regulator is shown in the lower one-third of Figure 2.13
.
The inputs to the bus voltage regulator are the bus voltage, the bus voltage
regulation set point Vreg, proportional gain, integral gain, and derivative
gain. The gains are intended to be internal values and not parameters. These
will be test points that are not visible to the user. Bus voltage regulation is
selected by the user in the Bus Reg Mode parameter.
Operation
Bus voltage regulation begins when the bus voltage exceeds the bus voltage
regulation set point Vreg and the switches shown in Figure 2.13
move to the
positions shown in Table 2.B
.
Table 2.B Switch Positions for Bus Regulator Active
SW 1 SW 2 SW 3 SW 4 SW 5
Bus Regulation Limit Bus Reg Open Closed Don’t Care
DB Bus
Motor Speed
Output Frequency
To Next Page
Loading...
Need help?
General
