Inverter is a power electronic device used to convert dc power into ac power at desired frequency and desired voltage level. Being a power electronic device, and due to absence of any rotating part and high switching ability, it is more efficient and reliable. Now a days an inverter is not only a device but also has become an important part of power industry but a simple inverter has only two level so the out coming wave is much distorted form fundamental sine wave of same time period and frequency which introduces the harmonics into the circuit which makes the total system less efficient along with that the heating effect of harmonics affects the age of system, also there is a danger of faulty operation [1,8]. As the presence of harmonics in the system have heating effect along with distortion which is not good for load as well as whole power system. So the concept of multilevel inverter came into existence in which the levels of the inverter is increased so that the distortion of the out-coming wave could be minimized [2].as the level rises the sinusoidal nature of the output wave increases and thus harmonic content decreases. In this paper a new asymmetrical multilevel inverter topology for 7 Level Inverter is proposed and its operation is being discussed and topology extended to 19 Level Inverter.

Keywords : Multi Level Inverter (MLI), Pulse Width Modulation (PWM), Phase Deposition Pulse Width Modulation (PDPWM),Phase Opposition Deposition Pulse Width Modulation (PODPWM), Alternate Phase Opposition Deposition Pulse Width Modulation (APODPWM).