Low voltage ride-through control of MMC valve in large-scale wind power systems based on transformer load forecasting
DOI:
https://doi.org/10.4108/ew.14631Keywords:
Modular Multilevel Converter, Negative-Sequence Current Control, Low Voltage Ride-Through, Circulating Current Suppression, Self-Attention Mechanism, Transformer-based Load ForecastingAbstract
INTRODUCTION: This paper investigates a fault ride-through control strategy for modular multilevel converter (MMC) based converter valves under low-voltage ride-through (LVRT) requirements in large-scale wind power transmission.
OBJECTIVES: To develop an enhanced LVRT control integrating hierarchical voltage balancing, dual-loop current control, and Transformer-based feedforward for improved dynamic response.
METHODS: Positive-/negative-sequence dual current inner-loop controller designed. Hierarchical submodule capacitor voltage balancing proposed. Transformer load forecasting using self-attention dynamically corrects active power reference.
RESULTS: Typhoon HIL validation under single-phase ground fault shows: negative-sequence current suppressed >90%; submodule capacitor voltage deviation decreases from 10% to 4.5%; circulating current effectively eliminated.
CONCLUSION: The strategy meets LVRT requirements in large-scale wind power transmission applications.
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Copyright (c) 2026 Yuhui Chen, Jiandong Tang, Xinxin Chen, Yu Wan
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