For the hybrid cascaded H-bridge inverter, when using the hybrid carrier cascade modulation strategy, although the problem of current backfilling can be solved and the waveform quality of the inverter output voltage is good, the lowvoltage unit of the inverter will have the problem of uneven power. Based on this, an improved hybrid modulation strategy was proposed. Taking the hybrid cascaded nine-level inverter as an example, the high-voltage unit of this strategy adopted step-wave modulation whose modulation wave was a sine wave. The modulation waves of the two low voltage units were adjusted respectively and then the pulse width modulation ( PWM) was carried out. The pulse signals of the switching components of the two low voltage units were obtained through PWM modulation. The logic operation was carried out by using the symmetry of the pulse signals and the pulse signals of the low voltage units were redistributed. Firstly, the simulation analysis was carried out, and the corresponding results were obtained by building simulation models and running the two modulation strategies under the same condition. Then, the experimental verification of the improved hybrid modulation strategy was carried out. Through simulation analysis and experimental verification, it is proved that the improved hybrid modulation strategy can reduce the carrier, simplify the modulation process, make the output voltage achieve frequency doubling effect, and solve the problem of power imbalance of the low voltage unit within 1 / 2 modulation wave period while retaining the advantages of the hybrid carrier cascade modulation strategy.