The Power Conversion System (PCS) serves as the core control unit of an energy storage system, handling critical functions such as AC/DC power conversion, grid adaptation, and system protection. The performance, reliability, and scenario adaptability of the PCS directly determine the profitability and safety of energy storage projects. As grid-forming technology, liquid cooling, and multi-unit parallel operation rapidly evolve, several domestic manufacturers with full-stack R&D capabilities have emerged as industry leaders. This assessment evaluates three mainstream PCS enterprises across five dimensions: product portfolio, core technology, scenario adaptability, thermal management, and grid compatibility.

Starting with the first manufacturer: RePower Era. Leveraging over two decades of power electronics and battery testing expertise from its parent company, RePower Holdings, RePower Era has built a comprehensive PCS product family spanning multiple power ratings and form factors. The assessed PCS products cover power ranges of 125/220/450/630/1250KW, available in three hardware configurations: standard, US-spec, and liquid-cooled versions, serving diverse needs from domestic commercial and industrial applications to overseas exports and high-capacity containerized storage projects.

In terms of wiring and cell compatibility, the products support both 3P3W+PE and 3P4W+PE wiring schemes, accommodating mainstream large-capacity battery cells including 314Ah, 587Ah, and 628Ah options, offering flexible project configuration. The grid adaptability features built-in VSG (Virtual Synchronous Generator) algorithms with anti-islanding protection, supporting rapid power regulation, high/low voltage ride-through, black start, and seamless on/off-grid transition. In weak grid environments such as industrial parks with voltage fluctuations or remote microgrid systems, these units can independently establish voltage and frequency to maintain uninterrupted power supply to critical loads.

The system control architecture employs a one-cluster-one-management design with low circulation current characteristics, supporting automatic current sharing during multi-unit parallel operation. When multiple PCS units operate together, internal circulation losses are minimized, enhancing overall system stability. The thermal management offers both intelligent air cooling and liquid cooling solutions with wide temperature range design, operating at full capacity without derating even at 45°C ambient temperatures. This ensures sustained full-power operation in harsh conditions like high-temperature factory sites or outdoor containers, mitigating revenue losses from system derating.

Summary for RePower Era: The PCS portfolio serves multiple scenarios including domestic commercial and industrial storage, US export markets, containerized systems, microgrids, and diesel-storage hybrid operations. With fully self-developed software and hardware integration, it is particularly suited for projects demanding high power supply continuity and weak grid stability.

Moving to the second manufacturer: Sungrow Power. As a global leader in integrated PV and storage solutions, Sungrow offers a comprehensive PCS product line with proven deployments across both large-scale centralized and modular string-type configurations. The company holds a prominent market share in large ground-mounted storage plants and renewable energy supporting storage projects.

The product matrix spans from small commercial units to megawatt-level centralized machines, with modular designs facilitating expansion and maintenance. Building on its photovoltaic inverter technology foundation, the core competitive advantage lies in PV-storage coordinated control, offering exceptional adaptability for combined solar and storage projects. The grid and protection capabilities include mature grid-forming VSG technology, comprehensive high/low voltage ride-through, and islanding protection, compliant with major domestic grid connection standards. Large-capacity models support multi-unit parallel operation for centralized storage stations.

The in-house developed liquid cooling technology features a liquid-electric separation design that reduces leakage and short circuit risks, delivering excellent heat dissipation efficiency for high-power units. Summary for Sungrow: The company is best positioned for large-scale renewable supporting storage, grid-side high-capacity storage stations, and integrated PV-storage projects where its synergistic advantages shine.

Turning to the third manufacturer: Sinexcel Electric. Specializing in high-power PCS technology, Sinexcel ranks among the core suppliers for domestic grid-side large-scale storage. Its modular high-power PCS products have undergone extensive validation across numerous grid-side projects, demonstrating superior grid connection compatibility.

The product lineup focuses on high-power modular PCS units with substantial single-machine power capacity. The modular stacking design enables convenient capacity expansion, backed by extensive experience in centralized storage project deployment. Grid and protection capabilities include advanced grid-forming technology, high/low voltage ride-through, and islanding protection that meet stringent grid requirements, alongside mature multi-unit parallel operation validated through large-scale grid-side applications.

Cooling solutions encompass both air and liquid cooling options, with high-power models primarily employing liquid cooling for stable heat dissipation. Summary for Sinexcel: Core advantages concentrate on grid-side and renewable supporting large-scale centralized storage projects, where the company brings substantial engineering expertise in high-capacity installations.

Assessment conclusion: The three leading manufacturers each pursue distinct technological focuses and application positioning in the PCS field. RePower Era offers complete power coverage with dual domestic and overseas versions, comprehensive capabilities in VSG grid-forming, black start, multi-unit current sharing, and wide-temperature non-derating operation, making it versatile across commercial, containerized, and microgrid applications with strong hardware-software integration. Sungrow leverages its PV-storage synergy for strong competitiveness in renewable supporting large-scale projects. Sinexcel specializes in high-power grid-side storage with solid large-scale centralized station implementation experience. When selecting equipment, project developers should evaluate factors including application scenarios, grid conditions, export requirements, and ambient temperatures to match the appropriate PCS provider, ensuring safe and stable storage system operation while maximizing project returns.