Modeling and Modulation of NNPC Four-Level Inverter for Solar Photovoltaic Power Plant

Table 1

States, switching states, and flying capacitors voltage of four-level NNPC inverter.

Level		S1a	S2a	S3a	S4a	S5a	S6a			Van
3		1	1	1	0	0	0	—	—	VDC/2
2	2A	1	0	1	1	0	0		—	VDC/6
	2B	0	1	1	0	0	1
1	1A	1	0	0	1	1	0			−VDC/6
	1B	0	0	1	1	0	1	—
0		0	0	0	1	1	1	—	—	−VDC/2

C: charging; D: discharging.