Patent ID: 8873260

Claim:
Method for controlling an output voltage of a boost converter composed of n bridge devices connected in series, each bridge device being composed of plural switches and a capacitor, the method comprising: preparing at least three periodical patterns, each periodical pattern being decomposed in time intervals, wherein, in each time interval of the first and at least one second periodical patterns, the voltage between the input and the output of each ith bridge device, with i from one to n, is equal to a null value, or a product of an integer number k i , as a first positive value that increases as i increases, and at least one second positive value, or a product of the number k i , negative one, and at least one second positive value, and in each time interval of at least one third periodical pattern, the voltage between the input and the output of each ith bridge device with i from one to n, is equal to a null value, or a product of an integer number p i and at least one third positive value, or a product of the number p i , negative one, and the at least one third positive value, wherein p i increases as i increases, and the at least one number k i is different from the number p i for each value of i; detecting that a periodical pattern has to be selected; selecting one periodical pattern from the at least three periodical patterns; and controlling the switches according to the selected periodical pattern.