MT-30
Installation, Operation & Maintenance
06225-03H.doc
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AeroVironment, Inc
General Limits Considerations
•
Set the upper/lower limits higher/lower than the maximum/minimum
commanded values.
•
Avoid over/under limit shutdown (caused by commanding mode
higher/lower than the set limits).
Operating Space
The operating limits define the
operating space
of the converter. The maximum
operating space for each configuration was depicted in the previous section. By
setting more restrictive operating limits, you reduce the operating space.
When operating inside the limits of the operating space, the DC Converter will
control the output based on the selected control mode and value. However, if one
of the boundaries of the operating space is reached, the DC Converter will
override the selected control mode and use the boundary condition as its internal
control mode if necessary to stay within the operating space.
Second Boundary
If a second boundary is encountered, the DC Converter will again override the
control mode and use the second boundary encountered as the internal control
mode if necessary to stay within the operating space. If the DC Converter is
unable to maintain the limits set by the user, it will automatically disconnect the
output terminals to protect the system and/or the load from a damaging failure. In
summary, the DC Converter will follow the limits set by the user in all cases.
Load
The load must exist in the operating space defined by the limits. A simple sketch
to determine the desired operating space will be useful and may avoid frustration.
Finally, there are a few basic rules that must be followed in setting the operating
limits. The DC Converter will enforce each of these rules.
1.
The lower current limit may not be higher than 0 Adc and the upper current
limit may not be lower than 0 Adc.
NOTE:
It is not recommended that either of these limits be set at exactly 0 Adc
because this may prevent the DC converter from controlling the voltage
(in Voltage Control Mode) as efficiently as possible at or near zero
current.
2.
The lower power limit may not be higher than 0 kW and the upper power
limit may not be lower than 0 kW.
3.
The operating limits may not be outside the maximum limits of the DC
Converter for the chosen configuration (as shown in the Tables and Figure
4.1).
4.
The upper limit for any parameter may not be lower than the lower limit for
that parameter.
Figure 4.4 shows an operating space defined by an upper voltage limit of 100
Vdc, a lower voltage limit of 20 Vdc, upper/lower current limits of ± 100 Adc,
and upper/lower power limits of ± 2 kW.
