I. Introduction
THE Modular Multilevel Converter (MMC) is a new topology of multilevel converter [1]–[3], which has gained wide attention in recent times (Figs. 1 and 2). The concept has been commercially implemented in HVDC applications as HVDC PLUS by a major manufacturer [4]. There are many attractive features of this converter, which are suitable for high power applications [1], [2]. The modular structure, advantage of easy scalability and a possibility of using redundant cells for fault tolerant applications are some of the key features of this converter. The output voltage quality of the MMC is almost close to sinusoidal, thereby putting minimum requirements on the design of the output filter. Many research works have been published in recent times highlighting the advantages of this converter for high power drive applications [5]–[9]. Modular Multilevel Converter One cell of the Modular Multilevel Converter