Enhancing the Fault Ride-through Capability of a DFIG-WECS Using a High-Temperature Superconducting Coil

Abstract

With the increase in doubly fed induction generator-based wind energy conversion systems (DFIG-WECS) worldwide, improving the fault ride-through (FRT) capability of the entire system has been given much attention. Enhancement of the FRT capability of a DFIG-WECS is conventionally realized by employing a flexible AC transmission system device with a proper control system. This paper presents a non-conventional method for the improvement of the FRT of DFIG-WECS, using a high-temperature superconducting coil interfaced with the DC-link of the rotor and stator side converters through a DC-chopper. A fractional-order proportional-integral (FOPI) controller is utilized to regulate the DC-chopper duty cycle in order to properly manage the power flow between the DC-link and the coil. Two optimization techniques, Harmony Search and Grey Wolf Optimizer, are employed to determine the optimum size of the superconducting coil along with the optimum parameters of the FOPI controller. The effectiveness of the two proposed optimization techniques is highlighted through comparing their performance with the well-known particle swarm optimization technique.

Enhancing low voltage ride through capability of grid connected DFIG based WECS using WCA-PSO tuned STATCOM controller

“…The DFIG has advantages such as variable speed capability, low initial cost, low converter rating, and active and reactive power controllability. However, DFIGs are susceptibility to faults at the grid side [ 4 , 24 ]. The DFIG has its stator connected directly to the grid, while its rotor is connected to the grid through a Power Electronic Converter (PEC), as shown in Figure 2 [ 3 ].…”

“…Therefore, power system operators worldwide have revised their Grid Code Requirements (GCRs) to incorporate Fault Ride Through (FRT) capability of wind farms. FRT capability is the ability of Wind Power Plants (WPPs) to remain connected to the grid during power system faults [ 3 , 4 ]. Under different undervoltage or overvoltage conditions, WPPs are required to stay online for a short, specified duration of time.…”

Supervisory Control Scheme of a Wind Farm Connected to a Hybrid Microgrid

“…SOSMC is another viable scheme [18] and is based on the sliding mode control approach with higher-order time derivatives. It will not only decrease the chattering phenomenon and avoid powerful mechanical efforts but will also maintain the good features of the sliding mode control [15,18,30].…”

Şebeke Bağlantılı Bir Fotovoltaik Sistemin Arıza Sonrası Yeniden Bağlanabilme Yeteneğinin Değiştirilmiş Bir PI Kontrolör Kullanılarak İyileştirilmesi

“…ASYBK çözümlerinin gerçek hayatta uygulanabilirliği açısından, cihaz içerisinde fazla yer kaplaması, aşırı ısınma, yüksek maliyet gibi bazı kısıtlar mevcuttur. Bu yüzden sistem kararlılığını ve güvenilirliğini artırmakla beraber ısınma, yer kaplama ve maliyet gibi konularda da kullanıcıları sıkıntıya sokmayan veya bu problemleri minimum düzeye indiren yaklaşımlara ihtiyaç duyulmaktadır [10,11]. Şekil 2'de akış diyagramı verilen bu çalışmada, şebeke bağlantılı bir FV sistemin ASYBK'sının geliştirilmesi amacıyla değiştirilmiş bir PI kontrolör önerilmiştir.…”