A Baseline Approach for Modeling and Characterization of Commercial Off-The-Shelf (COTS) Droop Controlled Converter

Abstract

Due to advancements in power electronics, new converter topologies are introduced day by day. It's hard to get an equivalent model from any manufacturer of any Commercial Off-The-Shelf (COTS) power electronics converters because of intellectual property (IP) and safety concerns. Most COTS products don't reveal the exact topology of the converter as well as the control architecture and corresponding control gains. Because of these reasons, it's very hard to implement an exact equivalent model of COTS converters. Hierarchical control is widely used in microgrid applications, where different control layers are decoupled on the timescale. This article gives a baseline approach to build an equivalent model of any droop controlled COTS converter to mimic its control performance. Bandwidths of the different control loops are estimated along with the control logic from experiments on COTS converter and then hierarchical control is followed to come up with the equivalent model. The approach is verified on COTS CE+T Stabiliti 30C3 converter with its equivalent model build in MATLAB Simulink.

Figures (15)

• Figure 1: Bandwidth decoupling of droop controlled converter
• Figure 2: Modeling of current loop
• Figure 3: Bode plot for current loop gain
• Figure 4: Modeling of voltage loop
• Figure 5: Bode plot for voltage loop gain