With the advent of the intelligent and energy-oriented era, the demand for electricity has increased significantly. To alleviate the pressures in aspects such as environmental pollution and energy consumption, the whole world is seeking green power generation methods, pinning high hopes on photovoltaic power generation. Under the advantages of policy support and the reduction of power generation costs by photovoltaic energy storage, household photovoltaic power generation and energy storage systems are gradually entering thousands of households.
A household energy storage system is similar to a miniature energy storage power station, and its operation is not affected by the pressure of urban power supply. During the off-peak electricity consumption period, the battery packs in the household energy storage system can be charged on their own for use during peak electricity consumption or power outages. Besides being used as an emergency power source, the household energy storage system can also balance the electricity load, thus saving household electricity expenses.
I. Basic Structure and Component Requirements of Household Energy Storage Systems
Currently, household energy storage is divided into two types: one is the grid-connected household energy storage system, and the other is the off-grid household energy storage system.
The grid-connected household energy storage system consists of five major parts, including: solar cell arrays, grid-connected inverters, BMS management systems, battery packs, and AC loads. The system adopts a hybrid power supply of photovoltaic and energy storage systems. When the mains power is normal, the load is powered by the photovoltaic grid-connected system and the mains power; when the mains power is cut off, the load is powered jointly by the energy storage system and the photovoltaic grid-connected system. The grid-connected household energy storage system is divided into three working modes. Mode 1: Photovoltaic provides energy storage, and the surplus electricity is fed into the grid; Mode 2: Photovoltaic provides energy storage and supplies part of the user's electricity; Mode 3: Photovoltaic only provides part of the energy storage. The grid-connected household energy storage is shown in Figure 1.
The off-grid household energy storage system is independent and has no electrical connection with the power grid. Therefore, the entire system does not require a grid-connected inverter, and a photovoltaic inverter can meet the requirements. The off-grid household energy storage system is also divided into three working modes. Mode 1: Photovoltaic provides energy storage and user electricity (on sunny days); Mode 2: Photovoltaic and energy storage batteries provide user electricity (on cloudy days); Mode 3: Energy storage batteries provide user electricity (in the evening and on rainy days).
The off-grid household energy storage is shown in Figure 2.
The gradual scale-up and popularization of household energy storage is a healthy and rational development trend for global future energy demands. Jiefeng Technology actively participates in the green development of energy technologies. Combining its own technological platform advantages and independent innovation capabilities, it provides a complete set of power supply solutions for household energy storage systems, simplifies the circuit schemes of household energy storage systems, reduces the construction and maintenance costs of household systems, and comprehensively enhances the stability, safety, and reliability of the systems.
