Performance of Electric Spring Under Varying Non-Critical Load Power Factor in Isolated Microgrid

Abstract

Smart loads have become one of the most trusted load-side power management devices used for voltage stabilization in isolated microgrid systems. This paper focuses on the performance study of a smart load used for voltage stabilization in an isolated system. To implement a smart load in a system first the system loads are divided into voltage-sensitive and voltage-insensitive categories. In this manuscript, a smart load combination is made from a bidirectional converter in series with the voltage-insensitive load. An in-phase voltage injection strategy has been suggested in this work for the control of the proposed smart load. The control strategy makes the electric spring capable of supplying both active as well as reactive power to the system. The performance of a smart load system greatly depends on the power factor of the non-critical load. The non-critical load power factor can affect the stability as well as the dynamic and steady-state performance of the system. This paper also investigates the sensitivity issues of the smart load with an in-phase voltage injection scheme for varying non-critical load power factors. The performance of the smart load at different power factors is also evaluated and the simulation results are shown in this work. A linearized model for the microgrid system is also developed in this work. The stability, transient and steady-state analysis of the proposed system is also included in this paper. The simulation and stability analysis of the system is carried out in MATLAB/Simulink environment.