A method of converting power, comprising: determining an operating mode of a gas turbine engine, wherein the operating mode is selected from a group including a start mode and a generate mode; wherein in the generate mode, the method further comprises the steps of: receiving AC power at a first set of phase legs, the first set of phase legs being connectable to the gas turbine engine; rectifying the received AC power into DC power using the first set of phase legs; receiving the rectified DC power at a second set of phase legs by flowing current through a DC link; and inverting the received DC power into AC power using the second set of phase legs, wherein, depending on the selected operating mode, one of the rectifying and inverting processes further includes switching respective outer switches comprised in the first or second phase legs set into an off state; wherein when it is determined that the operating mode is the start mode, the received AC power is constant frequency AC power, current flows through the DC link in a first direction, the inverted AC power is output as variable frequency AC power; and wherein when it is determined that the operating mode is the generate mode, the received AC power is variable frequency AC power, current flows through the DC link in a second direction opposite the first direction, and the inverted AC power is output as constant frequency AC power; wherein, in the generate mode, the outer switches are a plurality of outer switches arranged within the first phase legs set, and further including converting received variable frequency AC power into constant frequency AC power in the generate mode by opening the outer switches and routing current through diodes (126A, 126B, 126C, 128A, 128B, 128C) connected in parallel with the outer switches of the first phase legs set; characterized in that the opening of the outer switches creates a VIENNA rectifier with first phase legs set. receiving AC power at a first set of phase legs, the first set of phase legs being connectable to the gas turbine engine; rectifying the received AC power into DC power using the first set of phase legs; receiving the rectified DC power at a second set of phase legs by flowing current through a DC link; and inverting the received DC power into AC power using the second set of phase legs, wherein, depending on the selected operating mode, one of the rectifying and inverting processes further includes switching respective outer switches comprised in the first or second phase legs set into an off state; wherein when it is determined that the operating mode is the start mode, the received AC power is constant frequency AC power, current flows through the DC link in a first direction, the inverted AC power is output as variable frequency AC power; and wherein when it is determined that the operating mode is the generate mode, the received AC power is variable frequency AC power, current flows through the DC link in a second direction opposite the first direction, and the inverted AC power is output as constant frequency AC power; wherein, in the generate mode, the outer switches are a plurality of outer switches arranged within the first phase legs set, and further including converting received variable frequency AC power into constant frequency AC power in the generate mode by opening the outer switches and routing current through diodes (126A, 126B, 126C, 128A, 128B, 128C) connected in parallel with the outer switches of the first phase legs set; characterized in that the opening of the outer switches creates a VIENNA rectifier with first phase legs set.