Virtual Synchronous Machine Control for Doubly Fed Induction Machine-Based Wind Energy Conversion Systems

Abstract

Renewable inverter-based resources (IBRs), such as wind energy conversion systems (WSs), replace directly grid-connected synchronous machines (SMs). Standard grid-following (GFL) control of IBRs decreases the power system inertia. This paper proposes virtual synchronous machine (VSM) based gridforming (GFM) control for doubly-fed induction machine (DFIM) based wind energy conversion systems (WSs) with the following extensions: (i) feedforward torque control (FTC) for maximum power point tracking (MPPT), (ii) MPPT compensation for accurate inertia emulation, (iii) reference power point tracking (RPPT) to provide energy reserves, (iv) dynamic droop saturation control to mitigate power overloading, and (v) grid voltage control utilizing DFIM stator and rotor-side back-to-back inverter reactive power. The WSs are integrated into the IEEE 9-bus test system. Comprehensive simulation results give insights into (V)SM-based power system dynamics. Compared to existing VSM control without FTC, the proposed FTC increases the wind energy yield, i.e. typical MPPT performance is achieved, similar to GFL control. For high power penetration of IBRs, the proposed VSM control enables stable operation due to its GFM capability, whereas GFL control tends to instability. The VSM provides higher power system damping than a real SM due to (i) adaptable internal damping and due to (ii) faster droop control (if reserves available) which adapts the virtual turbine power without the dominant delays of real turbine dynamics.INDEX TERMS Doubly-fed induction machine (DFIM), grid-forming (GFM), grid-following (GFL), grid synchronization stability, power system dynamics, reserves, virtual synchronous machine (VSM), wind energy. NOMENCLATURE 2

Virtual Inertia Control for Power Electronics-Integrated Power Systems: Challenges and Prospects

“…As demand increases, additional conventional power deployment units are being built in different places [3,4]. However, these fossil fuel-based conventional power generation plants are producing harmful chemicals, such as carbon dioxide, nitrogen monoxide, carbon monoxide, sulphur dioxide, and other toxic pollutants in the open environment, which is catastrophically breaking the ozone layer of the environment, in turn contributing to high global warming every year [5,6]. Previous research studies have shown that the amount of carbon dioxide released into the atmosphere yearly from traditional power plants is 2.2 billion tons, which needs to Energies 2024, 17, 2737 2 of 33 be reduced by around 40%, according to the Paris Agreement, by 2030 [7,8].…”