BENSHAW M2L 3000, Руководство пользователя

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4 – Theory of Operation
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A typical 4160VAC inverter contains eighteen (18) cells, arranged 6 cells per phase as
shown in Figure 7. The cells are connected in series within each phase, and the
phases are connected in parallel across the internal DC bus. DC voltage is divided
evenly among the cells in each phase.
The cells in each phase work together to create the AC output waveform. Pulse width
modulation (PWM) control is used to convert DC voltage into a low distortion AC wave-
form, which is applied to the motor terminals labeled A, B and C in Figure 10. Each out-
put phase provides an equivalent waveform for optimal harmonic characteristics. As
such, output filters are not required. Additionally, the Inverter has been designed to
work with standard, non-inverter grade motors commonly found in use today.
Cell
Cell
Cell
Cell
Cell
Cell
Cell
Cell
Cell
Cell
Cell
Cell
Cell
Cell
Cell
Cell
Cell
Cell
+ DC
- DC
C
B
A
AC Outputs
Figure 10: 18 Cell Inverter
Inverter Packaging
The front view of a typical small frame 1500 hp Inverter is shown below in Figure 11.
Other specialized configurations of the Inverter can be utilized for higher horsepower
and/or voltage applications. The typical enclosure is partitioned into 3 sections: Cell, In-
put/Output and Control. The enclosure contains internal structural members that pro-
vide strength, rigidity and voltage isolation, with bolt-on metal covers for each section
attached to the structural members.
Control Section
Input/Output Section
Cell Section
Figure 11: Typical 1500 hp Inverter Front View