5MW Grid-Forming Energy Storage Power Conversion and Step-Up Integrated Unit (35kV)

This document presents a technical solution for a 5MW grid-forming energy storage power conversion and step-up integrated unit operating at 35kV. It begins with definitions of key terms such as battery energy storage system (BESS), power conversion system (PCS), and grid-forming PCS (GFM-PCS), including the concept of grid-forming volume ratio. The background highlights the urgent need for grid-forming support in new power systems characterized by high proportions of renewable energy and power electronics, as traditional thermal power declines. The solution details the overall design, main technical parameters, equipment layout, and civil engineering requirements. It covers the grid-forming energy storage power converter's electrical topology, technical advantages, core functions, and design features. Additionally, it describes the box-type transformer, high-voltage switchgear compartment, communication and power distribution cabinet, and auxiliary isolation transformer cabinet. Typical grid-forming energy storage solutions are provided, including unit configuration and comparison of different approaches. The document emphasizes the value and significance of grid-forming technology in enhancing grid stability and supporting renewable energy integration.