This topology can produce 5-level using a single dc source and 6 unidirectional switches. The voltage of capacitor usually half of the Vdc value. The topology can be extended to 7 levels by simply insert a capacitor and 2 more switches. However, the sensorless capacitor voltage approach is quite impossible since there is no way in the topology switching that can be utilized to make sure that the capacitor voltage is always at V/3