Parallel-Connected Inverter Control Method in Material Micromachining

摘要

This paper proposes a parallel-connected inverter control method for material micromachining. The proposed control method is composed of a sigmoid sliding mode function (SSMF) and a firefly algorithm (FA). The SSMF is insensitive to system uncertainties, thus achieving high-quality AC output voltage. However, as the load of the micromachining (MM) is a step change situation, steady-state errors still exist in SSMF. The steady-state errors cause heat losses in transistors and high voltage harmonics in inverter output, and thus the stability and reliability of the MM are degraded. To attenuate steady-state errors, the control gains of the SSMF can be tuned via the FA. Using the proposed control method, the parallel-connected inverter yields a high-quality AC output voltage with low voltage harmonics and fast dynamic response. Experiments prove the applicability of the proposed control method in material MM. Since the proposed control method is easier to implement than previous control methods and allows high-precision tracking, this paper will be of interest to designers of correlative material micromachining.