TY - JOUR

T1 - Analysis of Middle Frequency Resonance in DFIG System Considering Phase Locked Loop

AU - Song, Yipeng

AU - Blaabjerg, Frede

PY - 2018/1

Y1 - 2018/1

N2 - As the wind power technology develops, the Doubly Fed Induction Generator (DFIG) based wind power system, when connected to a weak network with large impedance, may suffer resonances, i.e., Sub- Synchronous Resonance (SSR) or High Frequency Resonance (HFR) when connected to the series or parallel compensated weak network. Besides these two resonances, a Middle Frequency Resonance (MFR) between 200 Hz and 800 Hz may appear when the Phase Locked Loop (PLL) with fast control dynamics is applied. In order to analyze the MFR, the DFIG system impedance considering the PLL is studied based on the Vector Oriented Control (VOC) strategy in Rotor Side Converter (RSC) and Grid Side Converter (GSC). On the basis of the established impedance modeling of the DFIG system, it is found that the PLL with fast control dynamics may result in the occurrence of MFR due to a decreasing phase margin. The simulation results of both a 7.5 kW small scale DFIG system and a 2 MW large scale DFIG system are provided to validate the theoretical analysis of the MFR.

AB - As the wind power technology develops, the Doubly Fed Induction Generator (DFIG) based wind power system, when connected to a weak network with large impedance, may suffer resonances, i.e., Sub- Synchronous Resonance (SSR) or High Frequency Resonance (HFR) when connected to the series or parallel compensated weak network. Besides these two resonances, a Middle Frequency Resonance (MFR) between 200 Hz and 800 Hz may appear when the Phase Locked Loop (PLL) with fast control dynamics is applied. In order to analyze the MFR, the DFIG system impedance considering the PLL is studied based on the Vector Oriented Control (VOC) strategy in Rotor Side Converter (RSC) and Grid Side Converter (GSC). On the basis of the established impedance modeling of the DFIG system, it is found that the PLL with fast control dynamics may result in the occurrence of MFR due to a decreasing phase margin. The simulation results of both a 7.5 kW small scale DFIG system and a 2 MW large scale DFIG system are provided to validate the theoretical analysis of the MFR.

KW - Controller parameters

KW - Doubly fed induction generator (DFIG) system

KW - Middle frequency resonance (MFR)

KW - Phase-locked loop (PLL)

KW - Parallel-compensated weak network parallel-compensated weak network

KW - doubly fed induction generator (DFIG) system

KW - parallel-compensated weak network

KW - middle frequency resonance (MFR)

KW - phase-locked loop (PLL)

UR - http://www.scopus.com/inward/record.url?scp=85032193742&partnerID=8YFLogxK

U2 - 10.1109/TPEL.2017.2672867

DO - 10.1109/TPEL.2017.2672867

M3 - Journal article

VL - 33

SP - 343

EP - 356

JO - I E E E Transactions on Power Electronics

JF - I E E E Transactions on Power Electronics

SN - 0885-8993

IS - 1

M1 - 7862270

ER -