Active filtering for common mode conducted EMI reduction in voltage source inverters

As solid-state power converters become more numerous, the unwanted EMI effects created by these converters increase. To address this issue, more attention has recently been given to the reduction of electromagnetic emissions created by power electronics. The proliferation of solid-state inverters brings the cost of semiconductors down, making active filtering an attractive alternative to passive filter topologies. Active filtering may also realize higher efficiency than passive filtering. This paper focuses on an active filter topology that significantly reduces the common mode voltage created by voltage source inverters. The reduction of common mode voltage is achieved by introducing a novel inverter topology and a new hysteresis modulation strategy to control this inverter topology.