PV Applications: Five Key Scenarios
Complete electrical assemblies are applied in PV projects across five key scenarios: combiner boxes (DC collection), inverter-related equipment (AC side), complete booster station assemblies (grid connection), box-type substations (on-site voltage step-up), and power distribution rooms (auxiliary power). Industry experts note that the application of these assemblies follows the system’s functional stages: DC side (combiner boxes/DC cabinets), inverter side (AC distribution cabinets), step-up side (box-type substations/booster station assemblies), grid-connection side (grid-connection cabinets/protection systems), and auxiliary power (low-voltage distribution).
Equipment selection for these complete PV assemblies (DC/AC/step-up) is based on the scale of the power plant.
Five Key Scenarios
- Combiner boxes: DC collection (gathering output from PV modules) and DC-side protection;
- Inverter-related equipment: AC distribution cabinets (handling inverter output) and AC-side power distribution;
- Booster station assemblies: Grid-connection assemblies (switchgear/protection systems) for voltage step-up and grid integration;
- Box-type substations: On-site voltage step-up (PV-specific box substations) and medium-voltage grid connection;
- Power distribution rooms: Auxiliary power (low-voltage distribution) for the power plant’s own operational needs.
Key Application Points
First, DC-side protection.
Combiner boxes provide DC protection (via anti-reverse diodes/fuses) and prevent hot-spot effects. Second, inverter matching.
AC distribution cabinets must match the inverter output capacity to prevent overloading.
Third, voltage step-up and grid connection.
Box-type substations or booster stations must match grid-connection voltage requirements and ensure compliance with grid-connection standards.
Fourth is standards and certification.
Ensure the complete PV system is certified (meeting IEC and grid-connection standards) and fully compliant.
Pitfalls to Avoid
First: Lack of DC protection.
Combiner boxes lacking protection (risk of hot-spot fires); ensure proper DC protection.
Second: Capacity mismatch.
AC cabinets with insufficient capacity (risk of overload); ensure capacity matching.
Third: Non-compliant grid connection.
Failure to meet grid-connection standards (risk of rejection);
ensure certification compliance.
Trends and Recommendations
Complete PV systems are trending toward higher capacities, specifically high-power string inverters and integrated PV-plus-storage solutions.
For end-users, the recommendation is to select complete systems based on specific application stages, ensure capacity matching, and verify certification compliance.
Proper application leads to highly efficient and stable PV power plants.
