Reduced-Rating-Electronic-Capacitor-Based DC Links for Power Electronics Supported Distributed Energy Resources

Electronic Capacitor (EC) is formed by a bidirectional DC-DC converter terminated with small auxiliary capacitance. The device is capable of mimicking the behavior of a bulk DC link capacitor while actually employing a component with much lower capacitance value. The paper demonstrates that forcing an EC to emulate a negative capacitance while connecting it in series with a passive capacitor leads to DC-DC converter rating reduction and subsequent potential volume reduction and efficiency increase of a DC link. Such a device may replace a traditional bulk DC link capacitor present in power electronics supported distributed energy resources in a plug-and-play manner. Simulations and experiments of a common dual stage AC/DC power conversion system employing the proposed active DC link validate the methodology.

Automated summary

This paper presents an electronic capacitor (EC) that can mimic the behavior of a bulk DC link capacitor while reducing the DC-DC converter rating. The device, which uses auxiliary capacitance, can be easily integrated into power electronics supported distributed energy resources, replacing traditional bulk DC link capacitors.