This paper presents the flexible power transformer (FPT) that consists of the integration of the standard power transformer and the multilevel rectifier- inverter back-to-back cascaded H-bridge (CHB) converter. The proposed technology pairs a fractionally-rated converter with a conventional transformer to offer a grid control solution at a lower cost-point and with higher reliability compared to existing approaches. The technology has been successfully simulated at the new energy system connecting power grid, 3- phase 66 kV, and lends itself to high voltage direct current transmission levels. Basic concepts and key technological aspects, along with simulation are presented for a 66 kV, 3- phase,$\pm 10\%$, 1 MVA converter and 66 kV, 3-phase,$\pm 50\%$, 5MV A converter. The simulation results show that the technology can stabilize the voltage of the new power system.