Control of static synchronous compensator with supplementary damping enhancement for wind farm voltage regulation

Abstract

This study presents a new control design approach for the wind farm voltage regulation using static synchronous compensator (STATCOM). A mode decoupling proportional plus integral (PI) controller, in which the control gains are synthesised by eigenstructure assignment (EA), is proposed for the STATCOM. EA is a state-space approach, which is used to improve system damping by eigenvalue assignment and alter system mode shape by eigenvector assignment. To embed the physical PI control loops in the state-space model, an equivalent transformation is proposed to map the feedback gain matrix to the PI controller. Owing to the presence of the physical PI control loops, the control signals would not mire into saturation when appropriate limiter according to the STATCOM capacity is placed in the control variables. To further alleviate the undesired oscillation mode excited by transient disturbance, a lead-lag-based supplementary damping controller (SDC) is adopted. Simulation comparisons are provided to show that the proposed technique can be an effective method for mitigating the voltage fluctuation in the wind farm because of the load changes and the wind gust.

A review ofSTATCOMcontrol for stability enhancement of power systems with wind/PVpenetration: Existing research and future scope

“…Hamdan et al 81 proposed a modified STATCOM controller to increase the dynamic performance and lower the voltage dips. The authors of References 82 and 83 adopt an eigen‐structure assignment approach for enhancing system stability. The technique is implemented by designing mode decoupling controllers based on eigenvalue assignment and eigenvectors to change the mode shape.…”

Power Smoothening Control of Wind Farms Based on Inertial Effect of Wind Turbine Systems

“…Then, the lead-lag compensator is used to compensate for the phase delay of the power reference, of which the transfer function, H comp (s), is expressed as [15] …”

Research and application of multiple STATCOMs to improve the stability of AC/DC power systems in China Southern Grid

“…By contrast, the response time of STATCOMs is typically less than one power frequency cycle and the STATCOMs can emit rated current or even short‐time overload currents during system transients. A rapid dynamic reactive power may remarkably enhance the voltage recovery capability of the HVDC inverter buses in the event of a system failure, and reduce the risks of continuous commutation failures of the HVDC transmission system [7–11]. The required footprint of a STATCOM is typically one third of that of a SVC, given that the STATCOM eliminates the need for bulk outdoor inductors and capacitor banks.…”