NEWS

Driven by the "double carbon" goal, new energy is one of the key work goals of the "14th Five-Year Plan". The National Energy Administration on the "New power system Development Blue Book" fully emphasizes the important role of energy storage in the construction of a new power system, this paper will focus on the common household photovoltaic + energy storage system types and characteristics.

1/ Hybrid home PV + energy storage system

System introduction

Hybrid PV + energy storage systems are generally composed of photovoltaic modules, lithium batteries, hybrid inverters, smart meters, CT, power grids, grid-connected loads and off-grid loads. The system can directly charge the battery through the DC-DC conversion, and can also realize the bidirectional DC-AC conversion for battery charging and discharging.

Working logic

During the day, photovoltaic power generation first supplies the load, then charges the battery, and finally the excess electricity can be connected to the grid; At night, the battery discharge supplies the load, and the insufficient part is supplemented by the grid; When the power grid is outage, photovoltaic power generation and lithium batteries are only supplied to the off-grid load, and the grid-connected load cannot be used. In addition, the system also supports users to set their own charging and discharging time to meet the needs of users.

System characteristics

The system is highly integrated, which can greatly reduce system installation time and cost

Intelligent control can be realized to meet the needs of users

The power grid can provide users with safe power when the power failure

2/ Coupled home PV + energy storage system

System introduction

Coupled photovoltaic + energy storage system, also known as AC retrofit photovoltaic + energy storage system, the system is generally composed of photovoltaic modules, grid-connected inverters, lithium batteries, AC coupled energy storage inverters, smart meters, CT, power grids, grid-connected loads and off-grid loads. The system can realize the conversion of photovoltaic into AC power by grid-connected inverter, and then the excess power is converted into DC power by AC coupled energy storage inverter and stored in the battery.

Working logic

During the day, photovoltaic power generation first supplies the load, then charges the battery, and finally the excess electricity can be connected to the grid; At night, the battery discharge supplies the load, and the insufficient part is supplemented by the grid; When the power grid is outage, the lithium battery only supplies power to the off-grid load, and the grid-connected load cannot be used. In addition, the system also supports users to set their own charging and discharging time to meet the needs of users.

System characteristics

The existing grid-connected photovoltaic system can be transformed into an energy storage system with low investment cost

The power grid can provide users with safe power when the power failure

Compatible with grid-connected photovoltaic systems from different manufacturers

3/ Off-grid home PV + energy storage system

System introduction

Off-grid home PV + energy storage systems are generally composed of photovoltaic modules, lithium batteries, off-grid energy storage inverters, loads and diesel generators. The system can directly charge the battery through the DC-DC conversion, and can also realize the bidirectional DC-AC conversion for battery charging and discharging.

Working logic

During the day, photovoltaic power generation first supplies the load, and then charges the battery; At night, the battery discharge supplies the load, and when the battery is insufficient, the load is supplied by the chai hair.

System characteristics

It can meet the daily demand of electricity in off-grid areas

It can be combined with a diesel generator to supply a load or charge a battery

Most separate network energy storage inverters have no grid-connection certification, even if the system has a grid, it can not be connected to the grid

4/ Photovoltaic energy storage management system

System introduction

Photovoltaic energy storage energy management system, the system is generally composed of photovoltaic modules, grid-connected inverters, lithium batteries, AC coupled energy storage inverters, smart meters, CT, power grids and control systems.

System characteristics

The control system can receive and respond to external instructions, respond to the power demand of the system, and accept the real-time control and scheduling of the system

It can participate in the optimization of the power grid operation, so that the use of electricity is more efficient and more economical