MT-30
Installation, Operation & Maintenance
06225-03H.doc
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AeroVironment, Inc
Figure 4.4. Example of a User-defined Operating Space
Given the operating space defined in Figure 4.4, the following two examples
describe how the system would respond to different loads.
Example 1: Resistive load
A resistive load has a current at its terminals that is in proportion to the voltage
across its terminals. Prior to connection, no current is flowing in the terminals,
and the voltage is by definition zero. If the resistive load is to be energized
successfully, the MT-30 DC Converter's operating space must include this initial
condition.
With the operating space defined in Figure 4.4, the lower voltage limit of 20 Vdc
is higher than the required starting voltage of 0 Vdc, so the DC Converter would
prevent the load from being connected. To correct the problem the lower voltage
limit would need to be changed to 0 Vdc.
Example 2: Battery load
A battery load can be modeled as a variable voltage source in series with a
resistive load. Assume that the battery has an open circuit voltage of 68 Vdc at a
low state of charge.
Prior to connection, the load exists at 68 Vdc and 0 Adc, which is within the
operating space defined in Figure 4.5. Therefore, the converter will connect to
the battery and operate in the commanded mode of operation.
Assume that the DC Converter is then operated in Current Mode and the user
selects a charging current of +25 Adc. This operating point is inside the operating
MT-30 User Defined Operation Limits
0
20
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-150
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Current (A)
Voltage (V)
