Smartbitt SBOL50KTIII-3, Руководство по обслуживанию

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4.2 PFC/Booster
Figure 4.2 PFC/Booster
As shown in the Figure 4.2, when Q1/Q2 is on and D1/D2 is off, the current will increase to store energy
in choke(L1/L2). When the Q1/Q2 is off and D1/D2 is on, the choke will release energy. Therefore, we
can control the current in chokes (input current) by regulating the time of Q1/Q2 on and off. There are three
independent PFC/Booster for each phase.
4.3 Inverter
The input of the three-level inverter topology is two DC voltages, and the output is an AC voltage, as
shown in the Figure 4.3. When Q1 and Q2 are on, Q3 and Q4 are off, the voltage of the middle point
bridge is +BUS. When Q1 and Q2 are off, Q3 and Q4 are on, the voltage of the middle point bridge is –
BUS. We can get any voltage waveform between ±BUS voltage from LC filter output by regulating the
duty cycle of Q1/Q2/Q3/Q4, including sine wave form.
Figure 4.3 three-level inverter
N
Q
1
Q
2
U
BUS+
U
BUS-
R/S/T
Battery
L
1
D
2
D
1
C
1
C
2
N
L
2
Q
3
Q
4
Q
5
Q
6
INV OUTPUT
+BUS
-BUS
N
C1
L1
C2
C3
D1
D2
Q1
Q2
Q3
Q4