If we have a single-phase inverter (figure 2), we'll command in opposition the two arms.
Thus, K¢2 is ON at the same time as K1 and K2 at the same time as K¢1. The potential P2 has the value -U/2 when the potential P1 has the value U/2 and reciprocally.
The voltage u¢, equals to P1 - P2 is thus equal to U during a half-period and is equal to -U during the other half-period (figure 3)
Figure 3
