Frequency Scan–Based Mitigation Approach of Subsynchronous Control Interaction in Type-3 Wind Turbines

Faris Alatar,Ali Mehrizi-Sani

doi:10.3390/en14154626

Abstract

Integration of wind energy resources into the grid creates several challenges for power system dynamics. More specifically, Type-3 wind turbines are susceptible to subsynchronous control interactions (SSCIs) when they become radially connected to a series-compensated transmission line. SSCIs can cause disruptions in power generation and can result in significant damage to wind farm (WF) components and equipment. This paper proposes an approach to mitigate SSCIs using an online frequency scan, with optimized phase angles of voltage harmonic injection to maintain steady-state operation, to modify the controllers or the operating conditions of the wind turbine. The proposed strategy is simulated in PSCAD/EMTDC software on the IEEE second benchmark model for subsynchronous resonance. Simulation results demonstrate the effectiveness of this strategy by ensuring oscillations do not grow.

Highlights

Approach of Subsynchronous ControlPower generation is shifting towards using renewable energy sources at an accelerating pace driven by climate concerns, decreasing costs, and the depletion of fossil fuels.According to the International Energy Agency (IEA), an additional 22,101 TWh is expected to be generated from renewable sources by 2040 while non-renewable energy generation is expected to drop by 9664 TWh in the same period [1]
This paper proposes the use of frequency scans to change the inner current loop gain values or the operating conditions of the wind turbine (WT) to mitigate subsynchronous control interactions (SSCIs)
Future research can look into replacing the lookup table that needs to be obtained with parametric equations

Summary

Introduction

Approach of Subsynchronous ControlPower generation is shifting towards using renewable energy sources at an accelerating pace driven by climate concerns, decreasing costs, and the depletion of fossil fuels.According to the International Energy Agency (IEA), an additional 22,101 TWh is expected to be generated from renewable sources by 2040 while non-renewable energy generation is expected to drop by 9664 TWh in the same period [1]. 743 GW with the 93 GW installed in 2020 according to the Global Wind Energy Council (GWEC) [2]. Most recent wind turbine (WT) installations are of Type-3, which employ a doubly fed induction generator (DFIG) with two back-to-back converters connecting the rotor side to the grid side [3]. Integration of wind turbines into the grid comes with issues that can be mainly categorized into two main types: operational issues and dynamic issues. The operational issues are related to the intermittent nature of wind energy whereas the dynamic issues are mostly related to fault handling [4], inter-area oscillations [5], resonances (both electrical and electromechanical), and interactions [6]

Methods

Findings

Discussion

Conclusion