A Novel Decentralized Inverter Control Algorithm for Loss Minimization and LVRT Improvement

TL;DR

This paper introduces two decentralized, model-free algorithms that minimize system losses and enhance LVRT capability in distribution grids with renewable energy sources, without requiring communication or grid topology knowledge.

Contribution

The paper presents novel decentralized algorithms that simultaneously reduce losses and ensure LVRT support, extending their functionality with advanced RES forecasting methods.

Findings

Significant reduction in system losses during normal operation.

Successful maintenance of LVRT capability during faults.

Algorithms operate effectively with local information only.

Abstract

Algorithms that adjust the reactive power injection of converter-connected RES to minimize losses may compromise the converters' fault-ride-through capability. This can become crucial for the reliable operation of the distribution grids, as they could lose valuable resources to support grid voltage at the time they need them the most. This paper explores how two novel loss-minimizing algorithms can both achieve high reduction of the system losses during normal operation and remain connected to support the voltage during faults. The algorithms we propose are decentralized and model-free: they require no communication and no knowledge of the grid topology or the grid location of the converters. Using local information, they control the reactive power injection to minimize the system losses. In this paper, we extend these algorithms to ensure the low voltage ride through (LVRT) capability of the converters, and we integrate them with state-of-the-art Wavelet-CNN-LSTM RES forecasting methods that enhance their performance. We perform extensive simulations on the real-time digital simulation (RTDS) platform, where we demonstrate that the algorithms we propose can achieve a substantial decrease in power losses while remaining compliant with the grid codes for LVRT makes them suitable for the implementation across the distribution system.