A Novel Fractional Harmonic $d\text{--}q$ Domain Based Power Line Signaling Technique for Power Converters in a Microgrid

Traditionally, the communication between power converters connected in a microgrid is established using a wired method or a wireless droop method. The shortcomings of these methods have opened up the possibility of power-line-based communication between converters. However, the conventional power line communication systems have the disadvantages of using high-frequency data carrying signals that are prone to attenuation. These systems also make use of explicit couplers, transmitters, and amplifiers that adds to the overall cost and infrastructure. In this paper, a novel fractional harmonic d-q domain based power line communication technique is proposed. A switched fractional harmonic current space vector is used to carry data. The primary control loop and the modulation algorithm of the converters are used for encoding and decoding of data. The proposed technique thus overcomes the disadvantages of the conventional power line communication systems and at the same time carries forward the advantages of it. The proposed technique is validated with sufficient experimental test results.

I. Introduction

The concept of microgrids has gained prime importance over the past few years. A microgrid is essentially a combination of a number of distributed energy resources (DERs) and loads spreading across a small area [1], [2]. The DERs are connected to the microgrid through power electronic converters. Thus, the proper coordination between these converters becomes an essential requirement for the smooth functioning of the microgrid. The level of interaction between the converters is one of the determining criteria for the control strategy adopted for the microgrid. Presently, the interaction is achieved either using a wired communication method or a wireless droop method.