NOVELTY - The step wave inverter (20) has bridge circuits (12) which control different Direct Current (DC) voltage inputs from one of multiple independently generated power sources into the primary windings (16B) of transformers (16). The bridge circuits are assigned different associated carrier waves that have frequencies that are multiple times greater than a frequency of a reference waveform and have predetermined carrier wave values that are independent of the voltage steps output by the bridge circuits.    USE - Step wave inverter for converting DC voltage from DC voltage source, such as battery bank, photovoltaic array or fuel cell, into AC voltage.    ADVANTAGE - Inherent transformer leakage inductance can be used to eliminate external inductance and filter output voltage. Attains sine-wave quality and reduces harmonic content in output voltage for all stand-alone inverters by applying filtering in output of transformer.    DETAILED DESCRIPTION - The step wave inverter also has one or more processors configured to use a Phase-Shifted Carrier Pulse Width Modulation (PSCPWM) scheme to operate the bridge circuits in order to modulate multiple variable width pulses onto multiple individual voltage steps output from the bridge circuits for a step wave Alternating Current (AC) output from the secondary windings (16A) of the transformers. The one or more processors compare each of the individual carrier waves with different points in the reference waveform to determine when to selectively have the bridge circuits associated with the different individual carrier waves connect the DC voltages to the transformers and modulate the variable width pulses onto the voltage steps output by the bridge circuits. An INDEPENDENT CLAIM is also included for a method for controlling a step wave inverter.    DESCRIPTION OF DRAWING(S) - The drawing is a circuit diagram showing a single-phase step wave inverter.    Bridge circuits (12)    Transformers (16)    Secondary windings (16A)    Primary windings (16B)    Step wave inverter (20)