Energy storage harmonic control

Why do battery energy storage systems have a harmonic problem?

In grid-connected mode, current-controlled battery energy storage systems (BESS) face the issues of harmonic caused by nonlinear loads and interactive instability under weak grids. Firstly, the mechanisms of mid-frequency oscillations (MFO) and mid-frequency harmonics (MFH) are revealed by the impedance network theory and the circuit principle.

Can a battery energy storage system suppress mid-frequency oscillations and MFH?

Conclusion This paper presents a quasi-harmonic voltage compensation control of current-controlled battery energy storage systems (BESS) for suppressing mid-frequency oscillations (MFO) and mid-frequency harmonics (MFH). The main conclusions are as follows.

What is a grid-connected battery energy storage system (BESS)?

Simple controller implementation. In grid-connected mode, current-controlled battery energy storage systems (BESS) face the issues of harmonic caused by nonlinear loads and interactive instability under weak grids.

Can a quasi-harmonic voltage compensation control strategy effectively suppress MFO?

Aiming at the above problems, this paper proposes a quasi-harmonic voltage compensation control strategy without any harmonic extractor and provides a detailed parameter design rule. The proposed control strategy can effectively suppress MFO by enhancing the damping between BESS and weak grids.

What is battery energy storage system (BESS)?

Battery energy storage systems (BESS) emerge as a popular solution due to the technological enhancement and cost reduction of batteries [, , ]. However, BESS faces the challenges of oscillations and harmonics, as depicted in Fig. 1. Power electronic devices are the core component for integrating distributed resources.

Can broadband harmonics be suppressed without harmonic extraction filters?

Finally, simulation and experimental results verify that the proposed control can effectively suppress broadband harmonics without harmonic extraction filters. Harmonic currents introduced by nonlinear loads are prone to cause grid current distortion.