Stability and Frequency Regulation of Inverters with Capacitive Inertia

TL;DR

This paper investigates the stability and frequency regulation of inverters with capacitive inertia, demonstrating stability conditions and controller design for networks, supported by numerical examples.

Contribution

It introduces a new model for inverters with capacitive inertia and analyzes their stability and frequency regulation in networks.

Findings

System is stable with constant power load

Frequency can be regulated with suitable controllers

Numerical example confirms effectiveness of the proposed method

Abstract

In this paper, we address the problem of stability and frequency regulation of a recently proposed inverter. In this type of inverter, the DC-side capacitor emulates the inertia of a synchronous generator. First, we remodel the dynamics from the electrical power perspective. Second, using this model, we show that the system is stable if connected to a constant power load, and the frequency can be regulated by a suitable choice of the controller. Next, and as the main focus of this paper, we analyze the stability of a network of these inverters, and show that frequency regulation can be achieved by using an appropriate controller design. Finally, a numerical example is provided which illustrates the effectiveness of the method.