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Chapter3. Specification and Operation
hapter3. Specification and Operation
hapter3. Specification and Operation
hapter3. Specification and Operation
N5000 INSTRUCTION MANUAL
N5000 INSTRUCTION MANUAL
N5000 INSTRUCTION MANUAL
N5000 INSTRUCTION MANUAL
3.2 Inverter features
N5000 is a Cascaded H-bridge type voltage inverter, which generates high 3-phase voltage by
cascading single-phase low-voltage inverters of insulated DC part.
Multi-winding transformer is used
for numbers of independent insulated DC parts. And input harmonics content is reduced by installing 36
pulse (3kV class: 18 pulse) diode rectification part with phase differences of windings.
The improved structure enabled N5000 to generate high quality output voltage without a filter
that reduces harmonics and to utilize previously established motors and cables.
3.2.1 Composition
N5000 is composed of transformer panel, inverter (power cell unit) panel and control panel as
shown in Figure 3-1.
Figure 3-1 composition of N5000 inverter panel
A dry type multi-winding transformer is equipped in transformer panel. The 2
nd
winding of Multi-
winding transformer is constituted of 3 phase-6 winding groups with 10 degree phase differences
so that each winding is connected to the input terminal of power cell unit inside inverter panel for
6kV class. And the 2
nd
winding of multi-winding transformer for 3 kV class is constituted of 3
phase-3 winding groups with 20 degree phase differences.
Cooling fans are installed on top of all transformer panels for both 3kV and 6kV classes. The air
groove is separated from inverter/control panel and used for self cooling.
Each phase of U, V, and W has its own serially connected 6 power cells so that the total number
of power cells is 18 for 6kV class. For 3kV class, each phase of U, V and W has serially connected 3
