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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
INPUT POWER
3 PHASE
3300V/3000V AC
3300/3000 VAC
INDUCTION
MOTOR
+20
0
0
0
-20
0
Figure 3-4-B. 3kV-class N5000 inverter electric circuit
DC power supplies for the power cells of 18 H-bridge type should be separated to generate
6600V/6000V voltage output in 6kV-class N5000 series inverter. So the number of the 2nd
windings is made equal as the number of the power cells by utilizing multi-winding transformer. 6
windings (3 windings in 3kV-class) of each group have 10 degree phase differences (20 degree in
3kV-class) with each other by grouping the 2nd windings to 3 phases to minimize the harmonics
which are generated by using diode rectification circuit in each of the power cells. The transformer
of this type makes rectification part of 36-pulses for 6kV-class and 18-pulses for 3kV-class so that
the THD (Total Harmonic Distortion) ratio of the 1st side of transformer can be reduced below 5%
which is complied with the IEEE std. 519-1992 (Harmonic Voltage and Current Limits).