A new frequency conversion device topology based on matrix rectifier and AC chopper called MCAC） is proposed, which is referred as AC chopper matrix converters. First, the basic configuration of these new topologies and the fundamental principle are introduced. Then, the validity and feasibility of the new topologies are tested by digital simulation and prototype experiments. The results indicate that the output voltage transfer ratio can be larger than 1.0, the output voltage waveform is very close to standard sine wave and the harmonic contents increase slightly, overcoming the drawbacks of conventional MCs that maximum voltage transfer ratio is 0.866. This study may provide inspiration for further engineering applications.