Enhanced Power Line Communication Strategy for DC Microgrids Using Switching Frequency Modulation of

Abstract

To improve the reliability of DC microgrids operation, an enhanced power line communication (PLC) strategy is proposed using switching frequency modulation (SFM) of a power converter. The proposed PLC strategy uses the voltage ripple on the DC bus voltage, which is inherently generated by converter’s switching activities as an information signal. By using the SFM, all microgrid components sharing the DC bus as communication channel can obtain power flow information with FFT analysis of DC bus line frequency. In addition, the operating performance of the DC bus voltage regulator is enhanced over a range of light load conditions.

Existing System

Frequency-Based Current-Sharing Techniques, Stabilization Techniques.

Proposed System

This paper proposes a DBCS using a SFM (SFM-DBCS) to overcome the power converter disadvantage as well as to improve communication performance in the DC MG. In previous research of the communication strategies, there is no consideration of the power conversion efficiency of the power converter used to regulate the DC voltage level and to generate the communication signals. The proposed SFM-DBCS uses the converter’s switching activities as the power-line transmitter. The voltage ripple synchronized with the switching frequency of the power converter becomes the information signal of the power flow in the DC MG without any additional wires and amplifier. Each converter detects the frequency information by using the FFT analysis of the DC bus line frequency. In addition, the switching frequency variation strategy is considered to enhance the soft switching capability of the power converter.

Architecture

The concept of the proposed PLC: SFM-DBCS