Full‐Capacity Wind Turbine with Inertial Support by Adjusting Phase‐Locked Loop Response

Abstract

This study presents a new concept for full‐capacity wind turbines (WTs) to emulate inertial response behaviour by optimising phase‐locked loop (OPLL). The proposed OPLL‐based concept can make full‐capacity WT spontaneously respond to frequency events in grid with no more need for frequency measurement and calculations of its variation or differential, which are usually required to calculate the desired extra support power or chosen to trigger a predetermined active power shape etc., in common methods. Comprehensive analysis and comparisons are presented for full‐capacity WT with two different generic control structures by establishing corresponding motion equations with regard to the active current dynamics. The established motion equations theoretically indicate that PLL dynamics and the related active power controls are in the equally important positions and greatly influence the frequency response behaviours of full‐capacity WT, which constitutes the theoretical basis of the proposed OPLL‐based methodologies. Simulated results demonstrate the feasibility and correctness of the OPLL‐based methodologies. The influences of key parameters concerned corresponding to each proposed OPLL‐based methodology are studied. Finally, the proposed methodologies for two generic control structures are also briefly compared and evaluated.

Inertia Provision and Small Signal Stability Analysis of a Wind-Power Generation System Using Phase-Locked Synchronized Equation

“…Based on the theoretical analysis and simulation results above, proper parameters tuning could increase both the inertial response ability of the DFIG and the small signal stability of the power system. The common research findings are obtained in [25] that decreasing the parameters in PLL with a constant ratio has no effects on the internal stability of PLL. However, this paper further illustrates that the small signal stability of the whole system is deteriorated under these parameters tuning.…”

“…(iii) The PLL-based inertia emulation method adopts the controlled delay lock technology, which provides the wind turbine generator (WTG) with the automated frequency response ability [23]. The current researches have calculated the inertia time constant of WTG with the frequency-domain expression [24,25]. Meanwhile, the separate effect of the PLL parameter on the small signal stability of the power system has been studied [26,27].…”

Modeling and Modulation of NNPC Four-Level Inverter for Solar Photovoltaic Power Plant

“…The capacitor voltage balance can be achieved with the redundant states. Taking one phase as an example, the variation of the flying capacitor voltage is defined as (2), where V ci is the flying capacitor voltage, i = 1, 2. The capacitor voltage can be balanced if ΔV ci is close to 0.…”

“…In recent years, the grid-connected wind and PV power systems have attracted considerable interests around the world [1][2][3][4]. Many industrialized nations have installed significant solar power capacity into their electrical grids, providing an alternative to conventional energy sources.…”

Coordinated Control Strategy for a Hybrid Wind Farm with DFIG and PMSG under Symmetrical Grid Faults

“…Variable speed-constant frequency (VSCF) wind turbines using doubly fed induction generators (DFIG) or permanent magnetic synchronous generators (PMSG) have been most widely used in newly-installed wind farms [6][7][8][9]. Hybrid wind farms consisting of traditional fixed speed induction generators (FSIG)-, DFIG-and/or PMSG-based wind turbines have been the trend for expanding the existing wind farms and constructing large-scale new wind farms when considering the installed capacity of wind farms, construction cost, grid codes, etc.…”