Co-Ordinated Control Strategy for Hybrid Wind Farms With PMSG and FSIG Under Unbalanced Grid Voltage Condition

Abstract

This paper investigates a control strategy for a wind farm with the direct-driven permanent-magnet synchronous generators (PMSG)-based wind turbines and the fixed speed induction generators (FSIG)-based wind turbines under unbalanced grid voltage condition. By controlling the PMSG-based wind farm to inject negative-sequence current for decreasing voltage unbalance factor (VUF) at point of common coupling (PCC), the double grid frequency oscillations in electromagnetic torque, active and reactive power output from the FSIG-based wind farm can be suppressed. In this paper, the maximum amplitude of the negative-sequence current provided by the PMSG-based wind farm under different average active power output and different VUF conditions is deduced, and the impacts of its phase angle on the VUF mitigation control effect are further studied. The improved control strategy of injecting negative-sequence current from the PMSG-based wind farm by the modified negative-sequence voltage and current double closed-loop control system is then developed. Finally, the correctness of theoretical analysis and the effectiveness of the proposed control strategy are validated by the experimental results.

Analysis and Control of Fault Ride-Through Capability Improvement for Wind Energy Conversion System Using Linear Active Disturbance Rejection Control With Correction Link

“…It follows that a i > 0, i = 0, 1, 2, 3, 4, 5, 6. According to the stability criterion of Lienard-Chipart, the sufficient and necessary condition for the stability of the system is that its odd-order Herwitz determinant is positive, that is, (12) and (13). Numerical calculation of equation (28) by MATLAB shows that, under the condition that the system control input gain b 0 is determined, the traditional LADRC and LADRC-CL systems can maintain stability for the controller bandwidth (ω c ) and observer bandwidth (ω 0 ) changing in a large range.…”

Integrated optimal active and reactive power control scheme for grid connected permanent magnet synchronous generator wind turbines

“…5-7 that the output wind power generation is highly affected by the WS and rotational speed variations. Moreover, grid connected WF may cause voltage quality problems [48][49][50][51][52][53][54], such as voltage variations, and voltage flicker, where the following equation can give the voltage variations at the point of common coupling PCC…”

Analysis and Control of Wind Power Grid Integration Based on a Permanent Magnet Synchronous Generator Using a Fuzzy Logic System with Linear Extended State Observer

“…The PMSG is supplied to the electrical grid system by means of the grid-side converter (GSC), machine-side converter (MSC), and control systems [5,6]. The fault ride-through (FRT) capability is one of the important issues for the operation system of the wind power system [7][8][9][10]. The grid connection requirements (GCRs) involve the operational condition control of the distributed power system [11].…”