1. Product Overview

The PV AC combiner box is a key device specifically used in PV power generation systems using string inverters. It is installed between the AC output side of the inverter and the grid connection point/load, and plays a vital role in the entire PV power generation system.

2. Internal Configuration

1. Input circuit breaker:The input circuit breaker is a crucial component of the PV AC combiner box, controlling and protecting the input current. When an abnormality such as an overload or short circuit occurs, the input circuit breaker quickly disconnects the circuit, preventing further escalation and ensuring safe and stable system operation.

2. Output circuit breaker:The output circuit breaker controls the current output from the combiner box to the grid connection point or load. It also provides overload and short-circuit protection, ensuring the output current meets system requirements. It also disconnects the circuit in the event of an anomaly, protecting subsequent equipment.

3. AC lightning arrester:AC SPDs protect combiner boxes and the entire photovoltaic power generation system from lightning overvoltage. During thunderstorms and other conditions, overvoltage from lightning strikes can cause serious damage to the system. AC SPDs divert the overvoltage to the ground, protecting the equipment.

4. Intelligent monitoring instrument (optional):Users can choose intelligent monitoring instruments based on their actual needs. These instruments can monitor the system's voltage, current, power, and energy in real time. By monitoring these parameters, users can promptly understand the operating status of the photovoltaic power generation system, identify potential problems, and address them promptly, thereby improving system management efficiency and reliability.

3. Main Functions

1. Current Convergence: One of the primary functions of a PV AC combiner box is to combine the output currents of multiple inverters. In large-scale PV power generation systems, multiple string inverters are typically used, and the output currents of each inverter need to be centrally combined for unified transmission to the grid connection point or load. A PV AC combiner box effectively combines the output currents of multiple inverters, improving overall system efficiency.

2. Protect the inverter: The combiner box protects the inverter from damage caused by the AC grid-connected side and load. If an abnormality occurs at the grid connection point or load, such as voltage fluctuation or short circuit, the combiner box immediately disconnects the inverter, preventing damage from abnormal current and extending the inverter's service life.

3. Improve system safety: As the inverter output disconnect point, the PV AC combiner box can conveniently cut off the inverter output during system maintenance and overhaul, preventing workers from electric shock during operation, improving system safety and protecting the personal safety of installation and maintenance personnel.

IV. Application Scenarios

PV AC combiner boxes are widely used in PV power generation projects of all sizes, including distributed PV systems and centralized PV power plants. Whether it's a rooftop PV power generation project, a ground-mounted PV power plant, or a photovoltaic agricultural greenhouse, PV AC combiner boxes can optimize system design and improve system safety and reliability.

With its rational internal configuration and powerful functions, the PV AC combiner box plays an irreplaceable role in PV power generation systems. It not only combines the output currents of multiple inverters, but also effectively protects the inverters, improves system safety, and provides a strong guarantee for the stable operation of PV power generation systems.