A Novel Sensorless Rotor Position Algorithm for Single Converter Integrated DFIG Systems
摘要
Conventionally, the bench mark direct power controllers (three level for real power and two level for reactive power) have been widely used to regulate the real power (true power) and reactive power (imaginary power) of doubly fed induction generators (DFIGs) for single VSC(S-VSC) interfaced systems. However, this benchmark DPC suffers from significant drawbacks, particularly increased total harmonic distortion (THD), steady-state active and reactive power perturbations, and poor in reactive power control under low-voltage ride through (LVRT) events. The investigation on LVRT with benchmark (traditional) DPC with S-VSC integrated DFIG is new, and it is fails to regulate reactive power leading to an increase in stator and rotor current magnitudes. In this work, the above-mentioned limitations are addressed using two, three-level HS controllers with the aid of a novel sensorless rotor position (SLRP) computation. The proposed SLRP computation generates optimized slip angles to obtain the effective rotor position. The results shows that the proposed approach minimizes the THD to 1.7%, reduction in stator reactive power perturbations by 65 W and reduction in real power steady-state perturbations by 86 VAr in various speed conditions, and provides effective control of reactive power during LVRT event, thereby enhances the overall performance and stability of S-VSC integrated DFIG systems.